Human Overpopulation: Causes, Effects, Problems & Solutions

Human Overpopulation: Causes, Effects, Problems & Solutions

Human overpopulation is an issue by itself.

But, if there is one thing that is a major cause of most other sustainability issues – it’s human overpopulation.

It makes sense – more people means more consumption (of food, water, natural resources etc.), and more emissions (greenhouse gases, waste etc.)

In this guide, we discuss the causes, effects, problems and potential solutions behind overpopulation.


Summary – Human Overpopulation

  • Human overpopulation is essentially the point where the number of humans in an area, region, city, country or the world, cannot be maintained
  • This might occur because there is not enough resources to support that number of humans, or because the man made systems or natural environmental begin to degrade in terms of their ability to support those humans
  • The number of humans in an area can increase because of increased birth rates, decrease in the mortality/death rates, and increase in immigration
  • Historically, technological revolutions or advances in technologies have increased populations e.g. the tool-making revolution, the agricultural revolution, and the industrial revolution – all of which allowed humans more access to food, resulting in subsequent population explosions.
  • The fertility rate is strongly influenced by cultural and social norms that are rather stable and therefore slow to adapt to changes in the social, technological, or environmental conditions.
  • Population increase rates tend to be highest in areas where children die young, where there is poverty (especially extreme poverty), and where there is lack of access to education
  • Religious and ideological opposition to birth control has been cited as a factor contributing to overpopulation and poverty
  • Guatemala is an example of a country whose average family size halved with the decrease in extreme poverty. Cambodia and Namibia are two countries who have gone through similar trends
  • Populations in some of the poorest countries in the world are expected to double and even triple by 2040-50
  • Overpopulation in poorer countries is highly undesirable as economic development falls far behind a point where there is proper capital available to invest in the people and the country to support them. If you add corruption and a lack of proper social and government systems, the picture that is painted for these countries is even bleaker
  • When developed countries face quicker population increases, it can place a strain on resources that were already depleting or stressed, such as a city’s water supply
  • Over population means more resources are needed by a population as a whole (with freshwater and drinking water being one key example – demand increases for this crucial resource), but also more waste is produced, and there is more pollution and environmental degradation. Economically, there are more consumers and employees/skills introduced to the economy, but also more labor and more competition for jobs.
  • The effects of overpopulation are compounded by overconsumption, broken or inefficient systems, ineffective technology, environmental pollution and degradation, and other factors
  • Technology can play a large role in providing enough resources for a population e.g. look at the difference between agricultural sectors in developing vs developed countries, as well as the capacity to produce electricity, provide cold food storage etc.
  • Perth in Western Australia is a dry city, but faces many of the same challenges as Cape Town (dry city, increasing population, prone to droughts). Perth was able to provide enough freshwater and Cape Town experienced a water shortage because of various factors like good governmental planning, investment in water treatment and recycling, investment in desalination plants and so on.
  • There is an argument made that rich countries use the most resources from the planet, while poorer countries receive few of the benefits as a whole
  • The US across many measures (along with other developed countries) consume far more resources per capita than many poorer countries
  • The most overpopulated cities tend to be in developing countries where poverty is rampant due to this overcrowding (leading to sickness, disease, death and so on)
  • Even in developed countries, cities deal with intense smog and pollution problems that exacerbate health and poverty issues. Labor prices can also start to diminish with an increase in labor
  • Solutions to overpopulation tend to focus around reducing poverty, lifting education rates, increasing the quality of health care and safety (especially for children), and investing in basic living resources for the poorest countries or countries with the highest fertility and population increase rates
  • Other general solutions include investing in technology to provide the most crucial resources in all countries, becoming clear on exactly how many people each city in the world can sustainably support with the technology, resources and systems they currently have, more education and access to healthcare for women in regards to pregnancy, education for men on contraception, enforcing birth laws/regulations for the most heavily populated and quickest growing cities and countries, and to examine our consumption and waste habits city by city. Cities might focus on quality of life as a measurement of how many people a city can support
  • Each city has it’s own capabilities and capacity to support different populations to different extents – it’s too general to examine overpopulation at the country or state/province level
  • Some people have suggested space colonization and making use of resources in space as an option in the future for further human population expansion
  • The world’s population currently sits at around 7 billion in 2019, and is forecasted to reach somewhere between 9 to 13 billion between 2050 to 2100
  • There is more information in this guide about whether humans and Earth might run out of resources in the future, and what might happen if we do


What Is Human Overpopulation?

Overpopulation occurs when a species’ population exceeds the carrying capacity of its ecological niche.

Human overpopulation occurs when the ecological footprint of a human population in a specific geographical location exceeds the carrying capacity of the place occupied by that group.

Overpopulation can further be viewed, in a long term perspective, as existing when a population cannot be maintained given the rapid depletion of non-renewable resources or given the degradation of the capacity of the environment to give support to the population

The term human overpopulation also refers to the relationship between the entire human population and its environment: the Earth, or to smaller geographical areas such as countries.

It is possible for very sparsely populated areas to be overpopulated if the area has a meagre or non-existent capability to sustain life (e.g. a desert).



Human Overpopulation Causes

Overpopulation can result from:

  • an increase in births (fertility rate),
  • a decline in the mortality rate,
  • an increase in immigration,
  • or an unsustainable biome and depletion of resources



  • The UN projects the population of the 48 poorest countries in the world will double from 850 million in 2010 to 1.7 billion in 2050.

Population Institute, via the


  • The higher the death rate for children in a region, the higher the birthrate… When people know their children will survive, they have few children. Addressing global poverty and keeping children alive is crucial for reducing overpopulation.



  • Poverty and the lack of access to education leads to higher birthrates and overpopulation.

– USAID, via


  • “Where rapid population growth far outpaces economic development, countries will have a difficult time investing in the human capital needed to secure the well-being of its people and to stimulate further economic growth. This issue is especially acute for the least developed countries, many of which are facing a doubling, or even a tripling of their populations by 2050.”

– UN Population Fund, via


  • When poverty rates drop, birthrates soon follow…
  • Extreme poverty in Guatemala has decreased by nearly 40% since 1992, and with that decline in poverty, the average family size has fallen from almost 6 children to just over 3.
  • In 1994, the average family in Cambodia had nearly 6 children; by 2015, extreme poverty (living on less than $1.25 per day) in Cambodia had fallen more than 40% and average family size had decreased by more than half.
  • The last 20 years in Namibia have seen extreme poverty rates fall by 20% and average family size halved.



  • From a historical perspective, technological revolutions have coincided with population expansion.
  • There have been three major technological revolutions – the tool-making revolution, the agricultural revolution, and the industrial revolution – all of which allowed humans more access to food, resulting in subsequent population explosions.
  • For example, the use of tools, such as bow and arrow, allowed primitive hunters greater access to more high energy foods (e.g. animal meat). Similarly, the transition to farming about 10,000 years ago greatly increased the overall food supply, which was used to support more people. Food production further increased with the industrial revolution as machinery, fertilizers, herbicides, and pesticides were used to increase land under cultivation as well as crop yields.
  • Today, starvation is caused by economic and political forces rather than a lack of the means to produce food.
  • Significant increases in human population occur whenever the birth rate exceeds the death rate for extended periods of time. Traditionally, the fertility rate is strongly influenced by cultural and social norms that are rather stable and therefore slow to adapt to changes in the social, technological, or environmental conditions.
  • For example, when death rates fell during the 19th and 20th century – as a result of improved sanitation, child immunizations, and other advances in medicine – allowing more newborns to survive, the fertility rate did not adjust downward, resulting in significant population growth.
  • Until the 1700s, seven out of ten children died before reaching reproductive age. Today, more than nine out of ten children born in industrialized nations reach adulthood.
  • There is a strong correlation between overpopulation and poverty. In contrast, the invention of the birth control pill and other modern methods of contraception resulted in a dramatic decline in the number of children per household in all but the very poorest countries.
  • Agriculture has sustained human population growth. This dates back to prehistoric times, when agricultural methods were first developed, and continues to the present day, with fertilizers, agrochemicals, large-scale mechanization, genetic manipulation, and other technologies.
  • Humans have historically exploited the environment using the easiest, most accessible resources first. The richest farmland was plowed and the richest mineral ore mined first. Ceballos, Ehrlich A and Ehrlich P said that overpopulation is demanding the use of ever more creative, expensive and/or environmentally destructive means in order to exploit ever more difficult to access and/or poorer quality natural resources to satisfy consumers.



  • An example of a country whose laws and norms are hindering the global effort to slow population growth is Afghanistan. “The approval by Afghan President Hamid Karzai of the Shia Personal Status Law in March 2009 effectively destroyed Shia women’s rights and freedoms in Afghanistan. Under this law, women have no right to deny their husbands sex unless they are ill, and can be denied food if they do.”
  • Religious and ideological opposition to birth control has been cited as a factor contributing to overpopulation and poverty.



Human Overpopulation Effects & Problems

More humans means more consumption (of food, water, natural resources etc.), and more emissions (greenhouse gases, waste etc.).

It also means more production in the business and industrial sectors which are some of the biggest contributors to environmental and wildlife destruction. We are talking intensive agriculture, manufacturing, mining, textiles, construction and demolition and so on.

Some issues that are exacerbated by increase in population are:


  • Overpopulation can mean that if there are too many people in the same habitat, people are limiting available resources to survive.
  • Advocates of population moderation cite issues like quality of life, carrying capacity and risk of starvation as a basis to argue against continuing high human population growth and for population decline.
  • Scientists suggest that the human impact on the environment as a result of overpopulation, profligate consumption and proliferation of technology has pushed the planet into a new geological epoch known as the Anthropocene.



  • Inadequate fresh water for drinking as well as sewage treatment and effluent discharge. Some countries, like Saudi Arabia, use energy-expensive desalination to solve the problem of water shortages.
  • Depletion of natural resources, especially fossil fuels.
  • Increased levels of air pollution, water pollution, soil contamination and noise pollution.
  • Changes in atmospheric composition and consequent global warming.
  • Loss of arable land and increase in desertification. Deforestation and desertification can be reversed by adopting property rights, and this policy is successful even while the human population continues to grow.
  • Mass species extinctions and contracting biodiversity from reduced habitat in tropical forests due to slash-and-burn techniques that sometimes are practiced by shifting cultivators, especially in countries with rapidly expanding rural populations; present extinction rates may be as high as 140,000 species lost per year. As of February 2011, the IUCN Red List lists a total of 801 animal species having gone extinct during recorded human history, although the vast majority of extinctions are thought to be undocumented.
  • Biodiversity would continue to grow at an exponential rate if not for human influence. Sir David King, former chief scientific adviser to the UK government, told a parliamentary inquiry: “It is self-evident that the massive growth in the human population through the 20th century has had more impact on biodiversity than any other single factor.” Paul and Anne Ehrlich said population growth is one of the main drivers of the Earth’s extinction crisis.
  • The Yangtze River dolphin, Atlantic gray whale, West African black rhino, Merriam’s elk, California grizzly bear, silver trout, blue pike and dusky seaside sparrow are all victims of human overpopulation.
  • High infant and child mortality. High rates of infant mortality are associated with poverty. Rich countries with high population densities have low rates of infant mortality.
  • Intensive factory farming to support large populations. It results in human threats including the evolution and spread of antibiotic resistant bacteria diseases, excessive air and water pollution, and new viruses that infect humans.
  • Increased chance of the emergence of new epidemics and pandemics. For many environmental and social reasons, including overcrowded living conditions, malnutrition and inadequate, inaccessible, or non-existent health care, the poor are more likely to be exposed to infectious diseases.
  • Starvation, malnutrition or poor diet with ill health and diet-deficiency diseases (e.g. rickets). However, rich countries with high population densities do not have famine.
  • Poverty coupled with inflation in some regions and a resulting low level of capital formation. Poverty and inflation are aggravated by bad government and bad economic policies. Many countries with high population densities have eliminated absolute poverty and keep their inflation rates very low.
  • Low life expectancy in countries with fastest growing populations.
  • Unhygienic living conditions for many based upon water resource depletion, discharge of raw sewage and solid waste disposal. However, this problem can be reduced with the adoption of sewers. For example, after Karachi, Pakistan installed sewers, its infant mortality rate fell substantially.
  • Elevated crime rate due to drug cartels and increased theft by people stealing resources to survive.
  • Conflict over scarce resources and crowding, leading to increased levels of warfare.
  • Less personal freedom and more restrictive laws. Laws regulate and shape politics, economics, history and society and serve as a mediator of relations and interactions between people. The higher the population density, the more frequent such interactions become, and thus there develops a need for more laws and/or more restrictive laws to regulate these interactions and relations. It was even speculated by Aldous Huxley in 1958 that democracy is threatened due to overpopulation, and could give rise to totalitarian style governments.

The effects of overpopulation are compounded by overconsumption. According to Paul R. Ehrlich:

Rich western countries are now siphoning up the planet’s resources and destroying its ecosystems at an unprecedented rate. We want to build highways across the Serengeti to get more rare earth minerals for our cellphones. We grab all the fish from the sea, wreck the coral reefs and put carbon dioxide into the atmosphere. We have triggered a major extinction event … A world population of around a billion would have an overall pro-life effect. This could be supported for many millennia and sustain many more human lives in the long term compared with our current uncontrolled growth and prospect of sudden collapse … If everyone consumed resources at the US level – which is what the world aspires to – you will need another four or five Earths. We are wrecking our planet’s life support systems.



  • poverty and environmental degradation are some of the main effects
  • the world’s resources shrink
  • resources can be unevenly distributed (less resources means the available resources will go to those who can most afford it)
  • there is a declining ratio of food producers to food consumers
  • There are not enough resources or available land for many struggling individuals to survive
  •  there are too many people trying to fill a limited number of jobs within an area (labor price is diminished)
  • The most overpopulated cities tend to be in developing countries where poverty is rampant due to this overcrowding.
  • Even in developed countries, the cities listed deal with intense smog and pollution problems that exacerbate health and poverty issues.
  • In less developed regions, there is a higher death rate for children and adolescents. Unsanitary living conditions threaten survival rates. This is especially evident in urban areas where crowding is so common that slums have grown rapidly.



Potential Human Overpopulation Solutions & Strategies

It appears some of the major solutions are:

  • Improve overall quality of life
  • Reduce poverty
  • Increase availability of jobs
  • Increase the level and availability of education
  • Increase access to quality healthcare and contraception
  • Give the option for safe abortions
  • Focus on countries in particular with high fertility rates (above the replacement level)


Note that overpopulation is a slightly different issue to overconsumption.

One of the big alternatives to controlling population levels, is to change the way we consume i.e. consume less, consume more efficiently.

Inventing new technology to cater for increased population levels is another option.

Even if human quality of life is maintained with increasing population growth – there are still sub issues like social issues, environmental issues and wildlife issues that must be addressed.

All these issues and sub issues bridge and work in together.


  • Changes in lifestyle could reverse overpopulated status without a large population reduction.



  • The key thing you can do to reduce population growth is actually improve health.

– Bill Gates, via


  • In order to combat poverty in the most overpopulated cities, education and economic growth are critical.
  • By engaging the government to work with its community, the government will better understand which challenges should be addressed first.
  • Therefore, education, paired with improved living conditions in cities, will help ensure children are surviving into adulthood.
  • These are the key ingredients to overcoming poverty and environmental pollution in overpopulated urban areas.



Proposed solutions and ways to mitigate overpopulation related issues according to are:

  • Several solutions and mitigation measures have the potential to reduce overpopulation.
  • Some solutions are to be applied on a global planetary level (e.g., via UN resolutions), while some on a country or state government organization level, and some on a family or an individual level
  • Some of the proposed mitigations aim to help implement new social, cultural, behavioral and political norms to replace or significantly modify current norms.
  • For example, in societies like China, the government has put policies in place that regulate the number of children allowed to a couple.
  • Other societies have implemented social marketing strategies in order to educate the public on overpopulation effects. “The intervention can be widespread and done at a low cost. A variety of print materials (flyers, brochures, fact sheets, stickers) needs to be produced and distributed throughout the communities such as at local places of worship, sporting events, local food markets, schools and at car parks (taxis / bus stands).”
  • Such prompts work to introduce the problem so that new or modified social norms are easier to implement. Certain government policies are making it easier and more socially acceptable to use contraception and abortion methods.
  • Scientists and technologists including e.g. Huesemann, Huesemann, Ehrlich and Ehrlich caution that science and technology, as currently practiced, cannot solve the serious problems global human society faces, and that a cultural-social-political shift is needed to reorient science and technology in a more socially responsible and environmentally sustainable direction.

Reducing Overpopulation

  • Education and Empowerment…
  • One option is to focus on education about overpopulation, family planning, and birth control methods, and to make birth-control devices like male and female condoms, contraceptive pills and intrauterine devices easily available.
  • Worldwide, nearly 40% of pregnancies are unintended (some 80 million unintended pregnancies each year).
  • An estimated 350 million women in the poorest countries of the world either did not want their last child, do not want another child or want to space their pregnancies, but they lack access to information, affordable means and services to determine the size and spacing of their families.
  • In the United States, in 2001, almost half of pregnancies were unintended.
  • In the developing world, some 514,000 women die annually of complications from pregnancy and abortion, with 86% of these deaths occurring in the sub-Saharan Africa region and South Asia.
  • Additionally, 8 million infants die, many because of malnutrition or preventable diseases, especially from lack of access to clean drinking water.
  • Women’s rights and their reproductive rights in particular are issues regarded to have vital importance in the debate….wherever women are put in control of their lives, both politically and socially, where medical facilities allow them to deal with birth control and where their husbands allow them to make those decisions, birth rate falls. Women don’t want to have 12 kids of whom nine will die.
  • Egypt announced a program to reduce its overpopulation by family planning education and putting women in the workforce.
  • It was announced in June 2008 by the Minister of Health and Population, and the government has set aside 480 million Egyptian pounds (about $90 million US) for the program.
  • Several scientists (including e.g. Paul and Anne Ehrlich and Gretchen Daily) proposed that humanity should work at stabilizing its absolute numbers, as a starting point towards beginning the process of reducing the total numbers.
  • They suggested the following solutions and policies: following a small-family-size socio-cultural-behavioral norm worldwide (especially one-child-per-family ethos), and providing contraception to all along with proper education on its use and benefits (while providing access to safe, legal abortion as a backup to contraception), combined with a significantly more equitable distribution of resources globally.
  • Business magnate Ted Turner proposed a “voluntary, non-imposed” one-child-per-family cultural norm. A “pledge two or fewer” campaign is run by Population Matters (a UK population concern organisation), in which people are encouraged to limit themselves to small family size.
    • Greater and better access to contraception
    • Reducing infant mortality so that parents do not need to have many children to ensure at least some survive to adulthood.
    • Improving the status of women in order to facilitate a departure from traditional sexual division of labour.
    • One-Child and Two-Child policies, and other policies restricting or discouraging births directly.
    • Family planning
    • Creating small family “role models”
    • Tighter immigration restrictionsPopulation planning that is intended to reduce population size or growth rate may promote or enforce one or more of the following practices, although there are other methods as well:
  • The method(s) chosen can be strongly influenced by the cultural and religious beliefs of community members.
  • Birth Regulations…
  • Overpopulation can be mitigated by birth control; some nations, like the People’s Republic of China, use strict measures to reduce birth rates.
  • Sanjay Gandhi, son of late Prime Minister of India Indira Gandhi, implemented a forced sterilization programme between 1975 and 1977. Officially, men with two children or more had to submit to sterilization, but there was a greater focus on sterilizing women than sterilizing men. Some unmarried young men and political opponents may also have been sterilized. This program is still remembered and criticized in India, and is blamed for creating a public aversion to family planning, which hampered government programs for decades.
  • Urban designer Michael E. Arth has proposed a “choice-based, marketable birth license plan” he calls “birth credits”. Birth credits would allow any woman to have as many children as she wants, as long as she buys a license for any children beyond an average allotment that would result in zero population growth. If that allotment was determined to be one child, for example, then the first child would be free, and the market would determine what the license fee for each additional child would cost. Extra credits would expire after a certain time, so these credits could not be hoarded by speculators. The actual cost of the credits would only be a fraction of the actual cost of having and raising a child, so the credits would serve more as a wake-up call to women who might otherwise produce children without seriously considering the long term consequences to themselves or society.
  • Another choice-based approach, similar to Arth’s birth credits, is financial compensation or other benefits (free goods and/or services) by the state (or state-owned companies) offered to people who voluntarily undergo sterilization. Such compensation has been offered in the past by the government of India.
  • In 2014 the United Nations estimated there is an 80% likelihood that the world’s population will be between 9.6 billion and 12.3 billion by 2100. Most of the world’s expected population increase will be in Africa and southern Asia. Africa’s population is expected to rise from the current one billion to four billion by 2100, and Asia could add another billion in the same period.
  • Because the median age of Africans is relatively low (e.g. in Uganda it is 15 years old) birth credits would have to limit fertility to one child per two women to reach the levels of developed countries immediately.
  • For countries with a wide base in their population pyramid it will take a generation for the people who are of child bearing age to have their families.
  • An example of demographic momentum is China, which added perhaps 400,000 more people after its one-child policy was enacted. Arth has suggested that the focus should be on the developed countries and that some combination of birth credits and additional compensation supplied by the developed countries could rapidly lead to zero population growth while also quickly raising the standard of living in developing countries.

Extraterrestrial Settlement & Space Colonisation

  • Various scientists and science fiction authors have contemplated that overpopulation on Earth may be remedied in the future by the use of extraterrestrial settlements.
  • In the 1970s, Gerard K. O’Neill suggested building space habitats that could support 30,000 times the carrying capacity of Earth using just the asteroid belt, and that the Solar System as a whole could sustain current population growth rates for a thousand years. Marshall Savage (1992, 1994) has projected a human population of five quintillion (5 x 1018) throughout the Solar System by 3000, with the majority in the asteroid belt.
  • Freeman Dyson (1999) favours the Kuiper belt as the future home of humanity, suggesting this could happen within a few centuries. In Mining the Sky, John S. Lewis suggests that the resources of the solar system could support 10 quadrillion (1016) people.
  • In an interview, Stephen Hawking claimed that overpopulation is a threat to human existence and “our only chance of long-term survival is not to remain inward looking on planet Earth but to spread out into space.”
  • K. Eric Drexler, famous inventor of the futuristic concept of molecular nanotechnology, has suggested in Engines of Creation that colonizing space will mean breaking the Malthusian limits to growth for the human species.
  • It may be possible for other parts of the Solar System to be inhabited by humanity at some point in the future.
  • Geoffrey Landis of NASA’s Glenn Research Center in particular has pointed out that “[at] cloud-top level, Venus is the paradise planet”, as one could construct aerostat habitats and floating cities there easily, based on the concept that breathable air is a lifting gas in the dense Venusian atmosphere. Venus would, like also Saturn, Uranus, and Neptune, in the upper layers of their atmospheres, even afford a gravitation almost exactly as strong as that on Earth (see colonization of Venus).
  • Many science fiction authors, including Carl Sagan, Arthur C. Clarke, and Isaac Asimov, have argued that shipping any excess population into space is not a viable solution to human overpopulation. According to Clarke, “the population battle must be fought or won here on Earth”. The problem for these authors is not the lack of resources in space (as shown in books such as Mining the Sky), but the physical impracticality of shipping vast numbers of people into space to “solve” overpopulation on Earth. However, Gerard K. O’Neill’s calculations show that Earth could offload all new population growth with a launch services industry about the same size as the current airline industry.
  • The StarTram concept, by James R. Powell (the co-inventor of maglev transport) and others, envisions a capability to send up to 4 million people a decade to space per facility.
  • A hypothetical extraterrestrial colony could potentially grow by reproduction only (i.e., without any immigration), with all of the inhabitants being the direct descendants of the original colonists.


  • Despite the increase in population density within cities (and the emergence of megacities), UN Habitat states in its reports that urbanization may be the best compromise in the face of global population growth. Cities concentrate human activity within limited areas, limiting the breadth of environmental damage. But this mitigating influence can only be achieved if urban planning is significantly improved and city services are properly maintained.



  • More than 200 million women in developing countries are sexually active without effective modern contraception even though they do not want to be pregnant anytime soon, according to the Guttmacher Institute, a reproductive health research group. By the best estimates, some 80 million pregnancies around the world are unintended. Although the numbers aren’t strictly comparable—many unplanned pregnancies end in abortion—the unintended pregnancies exceed the 78 million by which world population grows every year.
  • In the U.S., which is well informed and spends nearly 20 cents per dollar of economic activity on health care, nearly one out of every two pregnancies is unintended. That proportion has not changed much for decades. In every nation, rich and poor, in which a choice of contraceptives is available and is backed up by reasonably accessible safe abortion for when contraception fails, women have two or fewer children.
  • Educating girls reduces birthrates.
  • Worldwide, according to a calculation provided for this article by demographers at the International Institute for Applied Systems Analysis in Austria, women with no schooling have an average of 4.5 children, whereas those with a few years of primary school have just three.
  • Women who complete one or two years of secondary school have an average of 1.9 children apiece—a figure that over time leads to a decreasing population.
  • With one or two years of college, the average childbearing rate falls even further, to 1.7.
  • And when women enter the workforce, start businesses, inherit assets and otherwise interact with men on an equal footing, their desire for more than a couple of children fades even more dramatically.
  • Most of the drop in Chinese fertility occurred … as the government brought women by the millions into farm and industry collectives and provided them with the family planning they needed to stay on the job. Many developing countries—from Thailand and Colombia to Iran—have experienced comparable declines in family size by getting better family-planning services and educational opportunities to more women and girls in more places.



Top 20 Countries With Largest Populations In Total People

As of September 2018, these are the top 20 largest population countries:

  1. China – 1,416,221,148
  2. India –  1,357,226,853
  3. USA – 327,258,161
  4. Indonesia – 267,393,413
  5. Brazil – 211,204,519
  6. Pakistan – 201,628,675
  7. Nigeria – 196,949,995
  8. Bangladesh – 166,730,612
  9. Russia – 143,959,398
  10. Mexico – 131,100,059
  11. Japan – 127,121,981
  12. Ethiopia – 108,089,628
  13. Phillipines  – 106,853,251
  14. Egypt – 99,766,661
  15. Vietnam – 96,693,923
  16. Democratic Republic Of The Congo – 84,581,357
  17. Germany – 82,331,523
  18. Iran – 82,192,940
  19. Turkey  – 82,167,606
  20. Thailand – 69,214,108



Past, Current & Future World Population Stats & Forecasts/Projections, Including Population Growth

You can see past, current and future world population stats and forecasts here:

  • – countries with biggest population by 2060
  • – most populous cities by 2100


The world’s population will rise from just over 7 billion in 2012 to nearly 9.6 billion by 2050



  • The world population is currently growing by approximately 74 million people per year. Current United Nations predictions estimate that the world population will reach 9.0 billion around 2050, assuming a decrease in average fertility rate from 2.5 down to 2.0.
  • Almost all growth will take place in the less developed regions, where today’s 5.3 billion population of underdeveloped countries is expected to increase to 7.8 billion in 2050. By contrast, the population of the more developed regions will remain mostly unchanged, at 1.2 billion. An exception is the United States population, which is expected to increase by 44% from 2008 to 2050.



Fertility Rates, & Replacement Level Rates

“Replacement level fertility” is the total fertility rate—the average number of children born per woman—at which a population exactly replaces itself from one generation to the next, without migration.

This rate is roughly 2.1 children per woman for most countries, although it may modestly vary with mortality rates.

Sub-Saharan Africa is the exception to this fertility trend. Its total fertility rate was 5.4 during the 2005–10 period― double that of any other region―and is projected to decline only to 3.2 by 2050. These expected reductions in fertility rates reflect expectations of increasing urbanization, expected declines in child mortality, and increases in income, among other factors.



The birth rates by country development level are:

  • World – 2.5
  • More Developed – 1.7
  • Less Developed – 2.6
  • Least Developed – 4.3

– UNFPA, via


Carrying Capacity

Carrying capacity refers to the number of individuals who can be supported in a given area within natural resource limits, and without degrading the natural social, cultural and economic environment for present and future generations. The carrying capacity for any given area is not fixed.

It can be altered by improved technology, but mostly it is changed for the worse by pressures which accompany a population increase. As the environment is degraded, carrying capacity actually shrinks, leaving the environment no longer able to support even the number of people who could formerly have lived in the area on a sustainable basis.

No population can live beyond the environment’s carrying capacity for very long.

We must think in terms of “carrying capacity” not land area. The effects of unfettered population growth drastically reduce the carrying capacity in the United States.



Countries With The Worst Human, Wildlife & Environmental Issues

Rather than looking at overall population numbers – instead, look at whether the population has enough resources to meet demand, look at quality of life indicators, and look at population effect on humans, wildlife and the environment.

Also look at human density (also called overcrowding) – number of people per square mile in that city.

10 of the most overcrowded cities in the world in 2017 based on number of people per square mile are:

  • 1. Dhaka, Bangladesh – 16,235,000 total people, and 114,300 per square mile
  • 2. Hyderabad, Pakistan – 2,990,000 total people, and 106,800 per square mile
  • 3. Vijayawada, India – 1,775,000 total people, and 80,700 per square mile
  • 4. Chittagong, Bangladesh –  3,250,000 total people, and 75,600 per square mile
  • 5. Mumbai, India – 22,885,000 total people, and 67,300 per square mile
  • 6. Hong Kong, – 7,280,000 total people, and 66,200 per square mile
  • 7. Aligarh, India – 1,050,000 total people, and 65,600 per square mile
  • 8. Macau – 655,000 total people, and 65,500 per square mile
  • 9. Hama, Syria – 1,300,000 total people, and 65,000 per square mile
  • 10. Mogadishu, Somalia – 2,265,000 total people, and 64,700 per square mile



There is also a list of the fastest growing cities in the world –


Overpopulation In Developing vs Developed Countries

It’s quite clear from the above information that overpopulation occurs at different rates, and has different results in developing vs developed countries.












10. – most populous cities by 2100







Waste Pollution: Causes, Sources, Effects & Solutions

Waste Pollution: Causes, Sources, Effects & Solutions

Waste pollution is an extremely wide ranging issue.

There are many different types of waste, many different ways to categorise them, and the impact they can each have on the environment, humans, and other parts of society can be measured in various ways.

In this guide we look at what waste pollution is, the different types of waste, along with causes, sources, effects and potential solutions to waste pollution.

(Note – you can read specifically about plastic waste pollution in this guide)


 Summary – Waste Pollution

  • There’s many different types of waste, and each country, state and city/town (or region) faces a different picture when it comes to their own waste pollution issues
  • There’s many different ways to categorise the different types of waste
  • Waste can be categorized by municipal waste, and industrial waste (which includes commercial waste)
  • Waste can also be categorized by natural or man made, by sector, by type, by material and many types of specific or specialised waste
  • Municipal and household waste is generally far easier to track and report than industrial waste, and as a society, it’s estimated industrial waste far outweighs municipal waste amounts per year (some numbers indicate municipal waste only makes up around 3% of total waste, compared to industrial at 97%)
  • In general, it can be difficult to accurately track and report waste in a lot of countries for various reasons
  • Paper, food, yard trimmings, plastics, metals, wood and textiles tend to be the most common municipal waste according to EPA numbers
  • The most common industrial waste according to some sources are construction, mining and quarrying, manufacturing, households, waste treatment, services and energy supply
  • Although some waste might be far less common in terms of quantity, some waste are highly hazardous and have potential for a lot of damage – so quantity of uncontained waste, as well as the damage of each type of waste should be reported or measured (poorly treated or contained radioactive waste is one example)
  • With plastic in particular, there’s different types of plastic – single use plastic packaging can be wasted at a far high rate than say some construction plastics which can be used for years or decades
  • The most common waste found in oceans according to some sources are cigarette butts, food wrappers, plastic beverage bottles, plastic bottle caps, straws and stirrers, plastic bags, grocery bags, glass beverage bottles, beverage cans, and plastic cups and plates. Plastics found in fishing nets and lines also make up a % of ocean plastic waste and general waste. But, highly damaging and toxic waste can run off or be dumped into the ocean as well (fertilizers, pesticides, industrial chemicals, etc.)
  • Some of the main waste disposal or management options are landfill, recycling and incineration (pyrolysis and gasification are examples of other waste management processes that involve heat), with compost being another
  • Developed countries produce the most waste, but tend to manage and contain it better than developing, or low to middle income countries
  • Waste pollution occurs for various reasons, including but not limited to over-consumption, a complete lack of waste management systems in low to middle income countries, poorly contained or ineffective waste management systems, not recycling or composting enough, wasting too much food at the consumer stage, a lack of cold storage for food in poorer regions in the world, littering, improper disposal or sorting of waste by residents and businesses or the industrial sector, and using the wrong waste disposal method or a less eco friendly/sustainable disposal method for a particular type of waste
  • We can reduce waste pollution via reducing our waste, re-using and repairing items we throw out, recycling, upgrading and improving the effectiveness of waste management and containment systems especially in low to middle income countries, having harsher penalties for littering and improper disposal of waste, having a strong focus on industrial waste and the proper disposal and management of industrial waste, and becoming really clear as a society on the types of waste we should be producing and the best ways to dispose of or manage that waste
  • It makes sense that the most significant positive results seen in waste pollution worldwide might be to reduce waste/have a more circular economy, improve effectiveness and containment of low to middle income countries’ waste management systems, focus heavily on getting industrial waste management systems and disposal right and reporting on them more clearly (as they make up such a large % of overall waste, and becoming very clear in each city what the best overall waste management option is for each type of material (landfill, recycling, incineration, compost or other)
  • Waste management systems tend to be specific to a city i.e. San Francisco’s waste management system is very different to a waste management system in New Delhi for example
  • Overall, some questions each city might ask themselves about waste management are which sectors produce the most waste, which materials are most common, what are the most damaging wastes, and what are the social, economic, and environmental consequences of pursuing different waste management options
  • Waste management is very important for a city to get right – each national, state and local government must work with private or commercial waste management companies to come up with long term waste management solutions and strategies that suit them across all areas of society (environmental, economic, social, technological and so on). 


What Is Waste?

Waste is material we no longer want or need anymore, or that has become unusable


Types Of Waste

There are many different ways to categorise waste.

The main two might be:

  • Municipal Waste – waste that comes from our households. Examples are food, paper, plastic, yard trimmings, and so on. Waste might be collected by private companies on behalf of the municipalities.
  • Industrial Waste – waste that comes from industrial activity, such as from mines, factories, mills, workshops and so on. Examples are mining (rubble, topsoil), agriculture (fertilisers, pesticides, animal waste), food processing (plastics, paper, food waste), textiles, metal manufacture, and construction and demolition wastes (plasterboard, bricks, concrete etc.). Usually, licensed waste disposal companies (through EPA approved waste disposal programs for example in the USA) are responsible for collecting and disposing of industrial waste. You can read more about industrial waste on, and

Other ways waste might be categorised (apart from municipal and industrial) are:

  • By Sector – mining, agriculture, manufacturing, municipal etc.
  • By Type – liquid, solid, organic, recyclable and hazardous (according to
  • Material – plastic, paper, e waste, chemicals etc.

Note though that different authorities and organisations count and report different types of waste.

So, always look at what specific waste materials and waste types a waste report is including to get an idea of how broad or narrow the stats are.

For example, if you look at the Australian National Waste Report prepared by Blue Environment for the Department of Environment and Energy, their scope of reporting includes:

  • Waste generated in Australia, including solid non-hazardous materials and all hazardous wastes including liquids (an accompanying report, Hazardous Waste in Australia 20172 , considers hazardous waste in detail).
  • The report excludes waste from primary production activities (agriculture, mining and forestry), waste that is reused (such as in ‘tip shops’), pre-consumer waste that is recycled as part of a production process, and clean fill/soil (whether or not it is sent to landfill).
  • Waste sources are considered in three streams: municipal solid waste (MSW) from households and council operations; commercial and industrial (C&I) waste; and construction and demolition (C&D) waste.


A further list of specific wastes to be aware of are:

  • Agricultural waste
  • Animal by-products
  • Biodegradable waste
  • Biomedical waste
  • Bulky waste
  • Business waste
  • Chemical waste
  • Clinical waste
  • Coffee wastewater
  • Commercial waste
  • Composite waste
  • Construction and demolition waste (C&D waste)
  • Consumable waste
  • Controlled waste
  • Demolition waste
  • Dog waste
  • Domestic waste
  • Electronic waste (e-waste)
  • Food waste
  • Gaseous wastes
  • Green waste
  • Grey water
  • Hazardous waste
  • Household waste
    • Household hazardous waste
  • Human waste
    • Sewage sludge
  • Industrial waste
    • Slag
    • Fly ash
    • Sludge
  • Inert waste
  • Inorganic waste
  • Kitchen waste
  • Litter
  • Liquid waste
  • Marine debris
  • Medical waste
  • Metabolic waste
  • Mineral waste
  • Mixed waste
  • Municipal solid waste
  • Nuclear waste (see Radioactive waste)
  • Organic waste
  • Packaging waste
  • Post-consumer waste
  • Radioactive waste
    • Low level waste
    • High level waste
    • Mixed waste (radioactive/hazardous)
    • Spent nuclear fuel
  • Recyclable waste
  • Residual waste
  • Retail hazardous waste
  • Sewage
  • Sharps waste
  • Ship disposal
  • Slaughterhouse waste
  • Special waste – see hazardous waste



Domestic/Municipal Waste vs Industrial Waste

While the U.S. produces around 236 million tons of municipal solid waste every year, the numbers for industrial waste are far less clear.

Some estimates [for industrial waste] go as high as 7.6 billion tons of industrial waste produced every year.



It’s important to note that most reported waste stats out there are municipal waste only (such as the numbers you see in the EPA MSW report).

The reason for this is that it’s very difficult to track and report industrial waste simply because it comes from so many sources, is so varied and spread out, and there is no one system to catch, process and report all this waste.

Based on the above numbers, municipal waste (household waste) may only male up 3% of total waste, compared to industrial waste at around 97% of total waste. has a good article on the 97-3% municipal vs industrial ratio at


Other sources that write about industrial waste (and commercial waste) are:

  • – plastic generation by the industrial sector


Problems With Reporting & Estimating Waste

There are many issues that surround reporting waste in general, and from country to country.

It is most commonly measured by size or weight, and there is a stark difference between the two. For example, organic waste is much heavier when it is wet, and plastic or glass bottles can have different weights but be the same size.

On a global scale it is difficult to report waste because countries have different definitions of waste and what falls into waste categories, as well as different ways of reporting.

Based on incomplete reports from its parties, the Basel Convention estimated 338 million tonnes of waste was generated in 2001.

For the same year, OECD estimated 4 billion tonnes from its member countries. Despite these inconsistencies, waste reporting is still useful on a small and large scale to determine key causes and locations, and to find ways of preventing, minimizing, recovering, treating, and disposing waste.



What Is Waste Pollution?

Waste pollution is the introduction of one or multiple types of waste into the environment, that creates some type of negative impact.

It harms, affects or has some type of cost for humans, wild life and other living organisms, the natural environment (by soil contamination, air pollution, water pollution etc.), or the economy.

It may also have some other form of social consequence (e.g. disrupting aesthetics).

The specifics of waste pollution differs depending on the type of waste, and where it occurs.


Causes Of Waste Pollution

The causes of waste pollution are specific to the type of waste. 

For example, the causes of plastic pollution may be different to the causes of industrial sludge pollution.

But, some general causes for waste pollution might be:

  • Waste Generation 

An excess of waste material being generated at the production or consumption stage


  • Waste Treatment & Management

A lack of, or inadequate waste treatment and/or waste management systems, processes, facilities and technology

One example is an open or uncontained landfill where rubbish can easily leak from

Another example is a factory not treating their waste water (which might contain harmful chemicals and substances), and dumping it. Ideally, production processes would be closed loop when it comes to waste by products, so wastewater and other types of waste are treated and re-used where possible instead of being dumped without treatment.

Another example might be a waste incineration plant not having air pollution or gas capture technology, that captures greenhouse gases or air contaminants before they get into the atmosphere


  • Littering Or Dumping

Even if adequate waste management or waste treatment exists, some consumers and businesses may still litter or dump their waste out in the open.


  • Waste Regulation

A lack of waste pollution laws and regulations, or inadequate enforcement of these laws and regulations by government and local authorities.


Sources Of Waste Pollution

Sources for waste pollution might be divided into the overall waste sector (municipal, or industrial), and then looking at the industries or waste types or waste products that contribute the highest quantity or highest share of waste.

A few examples of sources might be:


Municipal/Household Waste

Most common Municipal Solid Waste generated in 2015 was:

  • Paper and paperboard – 25.9%
  • Food – 15.1%
  • Yard Trimmings – 13.2%
  • Plastics – 13.1%
  • Metals – 9.1%
  • Wood – 6.2%
  • Textiles – 6.1%
  • Glass – 4.4%
  • Rubber and Leather – 3.2%
  • Other – 2.0%
  • Miscellaneous Inorganic Waste –  1.5%

The total generation of municipal solid waste in 2015 was 262.4 million tons (U.S. short tons, unless specified) of MSW in 2015, approximately 3.5 million tons more than the amount generated in 2014. MSW generated in 2015 increased to 4.48 pounds per person per day. This is an increase from the 259 million tons generated in 2014 and the 208.3 million tons in 1990.



In 2009, the City of Chicago had the following split:

  • Paper – 29.5%
  • Organics – 29%
  • Plastic – 12.5%
  • Private Construction & Demolition – 12%
  • Textiles – 6.2%
  • Glass – 4.9%
  • Metals – 3.9%
  • Inorganics – 1.1%
  • Water Bottles & Coated Milk Cartons – 0.8%



Industrial Waste

Industrial waste is hard to measure and report. But, there are some sources that report industrial waste:

Waste generation in EU-28 in 2012 by sector was:

  • Construction – 33%
  • Mining & Quarrying – 29%
  • Manufacturing – 11%
  • Households – 8%
  • Waste Treatment – 7%
  • Services – 5%
  • Energy Supply – 4%
  • Agriculture, Forestry & Fishing – 2%
  • Wholesale Of Waste & Scrap – 1%
  • Water Treatment – 1%



Estimated Total Annual Waste by Sector in the UK in 2004 was:

  • Construction & Demolition – 31.7%
  • Mining & Quarrying – 28.8%
  • Industrial – 12.5%
  • Commercial –  12.3%
  • Household – 9.5%
  • Dredged Materials – 4.7%
  • Sewage Sludge – 0.6%
  • Agriculture (inc. Fishing) – 0.2%



In 2009, the City of Chicago generated the following %’s of waste from these sectors:

  • Construction & Demolition Debris – 59%
  • Private Industrial, Commercial, Institutional & Multi Unit Residential – 26%
  • Residential With 4 Units Or Less – 15%



In 2008, total waste generation in the EU-27 by sector was

  • Construction – 32.9%
  • Mining – 27.8%
  • Manufacturing – 13.1%
  • Household – 8.5%
  • Waste & Water Management – 7.3%
  • Other Sectors – 5.3%
  • Energy Sector – 3.5%
  • Agriculture/Forestry – 1.7%

In 2008, total waste generation in the EU-27 by type of waste/waste material was:

  • Mineral Waste/Soils – 65%
  • Household Wastes – 7.7%
  • Other Wastes – 6.5%
  • Combustion Wastes – 6%
  • Animal and Vegetable Waste – 4.4%
  • Metallic Wastes – 3.8%
  • Wood Wastes – 2.6%
  • Paper and Cardboard Wastes – 2.2%
  • Sorting Residues – 1.7%



In 2015-15, Australia produced the equivalent of:

  • 565 kg per capita of municipal waste,
  • 831 kg of construction and demolition waste,
  • 459 kg of fly ash,
  • and 849 kg of other commercial and industrial waste.



The EPA in Ireland also keeps stats on municipal, packaging, electrical and electronic equipment, end of life vehicles, tyres, hazardous materials, composting and anaerobic waste, construction and demolition, waste infrastructure and generation and treatment



Most Common Rubbish Found In The Oceans

Note that not all waste ends up in landfills, incineration, recycling or composting.

Some of it ends up in the ocean. Waste generated 50km or less from the coat line is most likely to end up in the ocean.

The most common items collected in ocean clean ups are (according to general reporting):

  • Cigarette Butts – 2,248,065
  • Food Wrappers (candy, chips, chocolate etc) – 1,376,133
  • Plastic Beverage Bottles – 988,965
  • Plastic Bottle Caps – 811,871
  • Straws & Stirrers – 519,911
  • Other Plastic Bags – 489,968
  • Grocery Bags (Plastic) – 485,204
  • Glass Beverage Bottles – 396,121
  • Beverage Cans – 382,608
  • Plastic Cups & Plates – 376,479

Trash, packaging, and improperly disposed waste from sources on land accounts for 80% of the marine debris found on beaches during cleanups and surveys.

Furthermore, one-third to two-thirds of the debris we catalog on beaches comes from single-use, disposable plastic packaging from food and beverage-related goods and services (things like plastic cups, bottles, straws, utensils, and stirrers).

The other 20% (one-fifth) of items making up marine debris are attributed to at-sea losses from accidental or deliberate discharges from ocean-going vessels, and from lost or abandoned fishing gear and traps.



Waste Disposal

  • Overall, not all waste is disposed of adequately – littering and mismanaged waste still occurs
  • Not all waste, particularly industrial waste is recycled when it should be
  • The main forms of waste disposal are recycling, landfill and incineration (with energy capture). Composting is another form of waste disposal, although more minor at this stage.
  • Household waste is usually collected by municipalities
  • Industrial waste is usually collected by licensed waste contractors (usually licensed or approved as part of a program by a country’s or states’ EPA or environmental government agency)
  • Hazardous waste, toxic waste and other specific wastes have to be treated and disposed of in different ways to general solid waste


When we talk about waste management or waste disposal, we are talking about all the activities and actions required to manage waste from its inception to its final disposal. This includes amongst other things collection, transport, treatment and disposal of waste together with monitoring and regulation. It also encompasses the legal and regulatory framework that relates to waste management encompassing guidance on recycling.



In 2015, these are the disposal stats for Municipal Solid Waste in the US:

  • 52.5% went to Landfill
  • 25.8% went to recycling
  • 12.8% went to Combustion with Energy Recovery
  • and 8.9% went to Composting



In 2014-15, Australia had the following waste stats:

  • 64 Megatonnes of waste generated
  • 35 Megatonnes went to recycling
  • 27 Megatonnes went to landfill
  • 2.3 Megatonnes went to energy recovery, which is burning waste and capturing the gas energy



Specifically for global plastic waste disposal:

  • In 2015, an estimated 55 percent of global plastic waste was discarded, 25 percent was incinerated, and 20 percent recycled.
  • If we extrapolate historical trends through to 2050 — by 2050, incineration rates would increase to 50 percent; recycling to 44 percent; and discarded waste would fall to 6 percent. However, note that this is based on the simplistic extrapolation of historic trends and does not represent concrete projections.



Sources that talk specifically about industrial waste management include:



Waste By Country

When looking at waste by country, it’s important to look at:

  • Total waste
  • Waste per capita
  • And then what happens with that waste – is it recycled, or dumped, or incinerated? How much waste pollution occurs via waste generation in that country?

All countries have different waste stats and behavior patterns, and even ways of reporting their waste statistics.


Developing vs Developed Countries

  • Developed countries produce more waste per capita because they have higher levels of consumption. There are higher proportions of plastics, metals, and paper in the municipal solid waste stream and there are higher labour costs. As countries continue developing, there is a reduction in biological solid waste and ash. Per capita waste generation in OECD countries has increased by 14% since 1990, and 35% since 1980. Waste generation generally grows at a rate slightly lower than GDP in these countries. Developed countries consume more than 60% of the world industrial raw materials and only comprise 22% of the world’s population. As a nation, Americans generate more waste than any other nation in the world with 4.5 pounds (2.04 kg) of municipal solid waste (MSW) per person per day, fifty five percent of which is contributed as residential garbage.
  • Developing nations produce lower levels of waste per capita with a higher proportion of organic material in the municipal solid waste stream. If measured by weight, organic (biodegradable) residue constitutes at least 50% of waste in developing countries. Labour costs are relatively low but waste management is generally a higher proportion of municipal expenditure. As urbanization continues, municipal solid waste grows faster than urban populations because of increasing consumption and shortening product life spans.



  • Compared to those in developed nations, residents in developing countries, especially the urban poor, are more severely impacted by unsustainably managed waste. In low and middle-income countries, waste is often disposed in unregulated dumps or openly burned. These practices create serious health, safety, and environmental consequences. Poorly managed waste serves as a breeding ground for disease vectors, contributes to global climate change through methane generation, and even promotes urban violence.
  • Managing waste properly is essential for building sustainable and livable cities, but it remains a challenge for many developing countries and cities. Effective waste management is expensive, often comprising 20%–50% of municipal budgets. Operating this essential municipal service requires integrated systems that are efficient, sustainable, and socially supported.



Waste By Country

OECD countries (the most developed countries in the world, produce a lot of the waste int he world.

These are 2013 figures of municipal waste generation per capita in some of the top waste generating countries in the OECD group:

  • Denmark – 751kg (per person)
  • United States – 725kg
  • Switzerland – 712kg
  • Australia – 647kg
  • Germany – 614kg
  • Ireland – 587kg
  • France – 530kg
  • Netherlands – 525kg
  • United Kingdom – 494kg
  • Italy – 484kg
  • Spain – 455kg
  • Turkey – 407kg
  • Canada – 403kg
  • South Korea – 358kg
  • Japan – 354kg

–, and


You can see a full world map showing waste per capita levels by country at

You can see a description of some of this information at

Some of what they said is:

The top producers of waste are said to be small and island nations including:

  • Kuwait
  • Antigua and Barbuda
  • St. Kitts and Nevis
  • Guyana
  • Sri Lanka

According to eC02 Greetings, in places such as Antigua, Barbados and St. Kitts, a large majority of waste is accumulated due to tourism. It added that of these countries do not have the necessary infrastructure for proper sanitation and waste removal.

The top producers in the developed world were said to be:

  • New Zealand
  • Ireland
  • Norway
  • Switzerland
  • United States



Waste By Region

Waste generation by region %’s are:

  • OECD region – 44%
  • East Asia & The Pacific – 21%
  • Latin America & The Caribbean – 12%
  • Eastern & Central Asia – 7%
  • Middle East & North Africa – 6%
  • South Asia – 5%
  • Africa – 5%



Overall, Worldbank found:

  • MSW (municipal solid waste) generation levels are expected to double by 2025 (due to population growth)
  • The higher the income level and rate of urbanization, the greater the amount of solid waste produced.
  • OECD countries produce almost half of the world’s waste, while Africa and South Asia regions produce the least waste.



You can read more in Worldbank’s Waste Generation chapter of their knowledge paper at


Exporting & Importing Of Waste

Waste is shipped between countries for disposal and this can create problems in the target country.

As an example, electronic waste is commonly shipped to developing countries for recycling, reuse or disposal. The Basel Convention is a Multilateral Environmental Agreement to prevent problematic waste disposal in countries that have weaker environmental protection laws. The Convention has not prevented the formation of e-waste villages.



Developing countries can suffer environmentally, but also their people and wildlife can suffer from importing waste.


China is an example of a country that used to accept a lot of the world’s waste and plastic, but has recently put in place import bans to stop some or most of the plastic importation.


Effects Of Waste Pollution (& Problems)

The effects of waste generation and ultimately waste disposal are extremely wide ranging.

Waste can have the following main effects:

  • Environmental – land, water and air (troposphere and atmosphere)
  • Humans – health and mortality
  • Economy – cost, poverty
  • Wildlife – health and mortality


Different wastes will have different levels of impact, for example:

  • Hazardous and toxic waste can be extremely damaging based on contact or leaching or seeping (e waste, chemicals, fertilisers, pesticides etc.)
  • A more common waste like plastic might not be as damaging to touch, but can be devastating via ingestion and entanglement for example


You can read a full breakdown of the pros and cons of each waste disposal method – recycling, landfill and incineration at


Waste generally affects developing countries significantly as they may not have the finances to maintain waste management facilities, and the poorest people have to live among the and near the waste pollution.


Other effects and impact of waste include:

  • Attracts rodents, parasites, diseases and bacteria
  • Expose animals and humans to hazardous materials – can cause cancer for example
  • Can pollute water
  • Can contaminate soil via leachate and hazardous waste
  • Can pollute air with methane, and contribute to climate change and global warming
  • Toxic waste materials can contaminate surface water, groundwater, soil, and air which causes more problems for humans, other species, and ecosystems.
  • Developing nations who can’t afford properly managed and secured waste disposal facilities suffer – the poor who live near the dumping sites, or who have no dumping sites, have to live in the waste
  • The economic costs of managing waste are high, and are often paid for by municipal governments



  • Man-made wastes are more hazardous to the environment. Cell phone, for instance are made of lead, mercury and plastic and so many millions of them get thrown as garbage. This kind of electronic garbage creates environmental problems.
  • E waste is an issue such as the harmful effects of the fire retardant being used to protect PCs and electronic appliances against fire.
  • mercury will leach when certain electronic devices, such as circuit breakers are destroyed.
  • Batteries are an environmental hazard. The acid leaches not only into the soil but also goes into the ground water. Disposing of them also creates their own problems as the lead is likely to remain in the ash and be released in the air.



  • Chemicals contaminating soil – When waste ends up at the landfill, chemicals in the trash can leech out into the soil, contaminating it. This will hurt plants, along with animals and even humans who come into contact with the soil. Once polluted, contaminated soil can be very hard to clean, and will likely have to be dug up to clear the area.
  • Surface water – Chemicals don’t just run from garbage into the soil. They can also reach nearby surface water, such as rivers and lakes. This will change the levels of chemicals in the water for the worse. The result? The ecosystems such as fish habitats in the water get hurt, as do any creatures that drink from the water source
  • Air pollution – Garbage can create air pollution due to gasses and chemicals evaporating from the waste. This air pollution can occur in open-air dumps, where a lot of our waste and electronic trash goes, and through incinerators used at garbage disposal sites. The air pollution from incineration can be so bad, in fact, that it can even release toxic substances that can contribute to acid rain. Other garbage will release methane as it wastes away, and methane is one of the greenhouse gases that contribute to global warming – and can also be ignited to cause an explosion.



  • Pollution – If a landfill site is not properly sealed, a toxic pollutant known as leachate can escape into the surrounding groundwater causing environmental problems for plants and animals living downstream. Leachate is a liquid pollutant caused by waste breaking down that contains high levels of heavy metals, chemical compounds, pesticides and solvents which filter down into the bottom of a landfill site. Many modern landfills created today have a sealed barrier to prevent liquid pollution from entering groundwater, however the growing level of waste generation can increase the risk of leachate pollution.
  • Litter – Lightweight materials like plastic bags and film (such as lolly/chip wrappers) can easily be dispersed from rubbish bins and landfill into the surrounding environment by the wind and rain. Much of this lightweight material presents a range of hazards for wildlife and domestic animals who can become entangled or choke if they accidentally mistake litter for food. The chemical composition of plastic means that it takes a substantial period of time to break down in the environment, and is capable of travelling long distances without decomposing. Around 80% of plastic litter found in the ocean has travelled there from inland waterways. Oceanic currents have directed much of this material to a litter-made island in the mid Atlantic Ocean called the Great Pacific Garbage Patch. Items as large as computer monitors and tyres, as well as plastic twine, bottles and other material have been found here from across the world.
  • Loss of biodiversity – Demand for new landfill sites results in the clearing of large amounts of vegetation and alterations to the natural environment. This can displace hundreds and thousands of species (both plants and animals) which live in the surrounding habitat. Over time, excessive land clearing can result in the extinction of many of these species, and a significant loss of biodiversity.
  • Pests – Once the natural habitat has been removed by land clearing, many native species may no longer be able to compete with non-native species such as weeds, vermin, flies and rats. Unlike native species, these pests can often live on a vast variety of food sources and are better adapted to live on these landfill sites. As a result, foreign species such as rats, ibis, feral cats and dogs thrive in landfill areas on rotting food sources.



  • Waste products create air, water and soil pollution/contamination
  • Economic – a lot of money is spent to counter the effects of improper waste management and waste management in general
  • Oil spills create water pollution
  • Leaching of chemicals into soil and water creates pollution
  • Burning of any disposed waste and plastic materials results in air and environmental pollution.
  • Though we all are familiar with common methods of waste management like landfills, incineration, recycling, biological processing or energy conservation; we find ourselves living in a world filled with waste. Renewable energy and recycling took us to newer heights, but the adverse effects of improper waste management continue to plague us.
  • Waste management and soil contamination – contamination results when hazardous substances are spilled or buried in the soil. It can also occur when pollutants settle on the soil, such as chemicals or industrial smokestack. Plants in contaminated soil absorb hazardous substances. Humans or animals ingest these plants and may get sick. They can also inhale soil contaminants through dust that is present in the air or absorb these hazardous chemicals through their skin.
  • Water pollution, especially groundwater – heavy metal, pesticides, nitrates, petro chemicals, chlorinated solvents all have ability to seep into soil and ground water and rivers and lakes. Crops can absorb toxic chemicals. Soil fertility can decrease and crop yield can decrease. Fluoride, arsenic and salts can also seep into lakes. 97% of the world’s freshwater is in auqifers/groundwater. 1.5 billion people worldwide rely on groundwater for drinking water. Groundwater is also used for irrigation and even to makes bottled water.
  • Plastic water bottles eventually break down to release a harmful component called, DIETHYLHYDROXYLAMINE (DEHA). (A carcinogen which hurts our reproductive capabilities, causes liver dysfunction and weight loss issues.)
  • DEHA seeps into the surrounding areas of the soil and water bodies to harm the animal and plant life depends on it.
  • Water easily absorbs chemicals and toxic substances in rainfall, air, soil and other water sources. This damages the water source, animals and humans
  • greenhouse gases are created from decomposing waste which contribute to climate change. How else are we impacted? Well, apart from temperature what is also drastically affected is the level of precipitation in the air. From acid rain to severe hail storms or global warming – everything is fair game at present. This also spreads out into other areas with regards to subdivisions such as thermal and radioactive pollution.
  • Incineration and landfill both create harmful gases.
  • continual dumping of garbage, raw or untreated sewage. Any animal or marine life coming in contact gets impacted in the worst of ways. The inevitable formation of algal bloom and clusters contaminates and eventually suffocates marine life such as coral and fish.
  • consumption of fishing lines, cigarette butts, plastic bottles and Styrofoam can kill millions of marine lives each year.
  • Waste is dumped into the ground, Absorbed by the soil and groundwater, Waste contaminates the land on which we grow food and provides water for us and animals, Waste in the marine life kills fish, Carcasses float on the surface, and we see mosquitoes feed on it, The diseases carrying mosquitoes now spread sickness and death among the living population
  • People who live near landfills, waste disposal workers and people who come into contact with hazardous waste at manufacturing plants and on farms are at risk
  • Think about the fires at landfills and its effects on us. Whether coming from the air or its accumulation in our cellars, those landfill gases have been exposed for causing cancer, create respiratory and visibility problems, and the explosion of cans put people nearby at constant risk.
  • Additionally, when we come in contact with waste, it causes skin irritation and blood infections.  We also contract diseases from flies which are carriers of illnesses after breeding on solid waste. With regards to mosquitoes, we know, besides feeding on dead fish, they find sewage, rainwater, tires, cans and other objects to be ideal breeding grounds. They carry and spread diseases such as malaria and dengue. With an abundance of disease-carrying pests, it becomes difficult to be vigilant about waste management facilities. Despite all efforts, for example, rats continue their massive infestation on such facilities and sewage systems. They harm crops, spread diseases such as Hantavirus Pulmonary Syndrome, Leptospirosis, Rat-bite Fever and Salmonellosis. Waste management is our responsibility for we benefit and suffer from it in radical ways. Education and awareness across all communities, irrespective of their social, economic condition, must be ever-present for as long as life inhabits this planet. A butterfly fluttering its wings 900 miles away from you can cause a hurricane right where you live. Therefore, significant mismanagement of waste by Turkey and Chile, where only 1% of waste was reported to be recycled, can contribute to global warming. Even if you live far away in Greenland, there is no escape. We must all play a role.



Other resources on problems and effects of waste pollution are:



Trends & Stats On Waste Generation & Disposal

You can find more MSW (Municipal Solid Waste) waste generation trends at:


You can find more MSW waste disposal trends at:


You can find plastic disposal trends at:


You can find Australia’s waste trends in:


You can find more on industrial waste trends at:



More stats and trends on waste are available at:



Forecast For Waste Generation

Population growth, urban expansion and other factors look to increase waste generation rates in the future. However, variables such as waste reduction efforts, hitting peak population and population decline, and other variables may impact the rate of waste generation going into the future.


  • Around the world, waste generation rates are rising. In 2012, the world’s cities generated 1.3 billion tonnes of solid waste per year, amounting to a footprint of 1.2 kilograms per person per day. With rapid population growth and urbanization, municipal waste generation is expected to rise to 2.2 billion tonnes by 2025.
  • Solid waste generation rates are rising fast, on pace to exceed 11 million tonnes per day by 2100. That growth will eventually peak and begin to decline in different regions at different times, depending in part on population growth, waste reduction efforts, and changes in consumption. Until that happens, the rising amount of waste means rising costs for governments and environmental pressures.



A guide on how hazardous waste affects the environment can be found at:



Solutions To Waste Pollution

Just a few of the key ways to address waste pollution might be:

  • Better waste management facilities, and secured waste disposal and treatment – particularly in low to middle income countries. This may significantly reduce the amount of waste escaping uncontained and open landfills for example.
  • Be more efficient and produce less waste in developing countries – look at consumption patterns, reduce consumption, and look at ways for businesses and producers to address wastage rates (re-designs and changing processes could be key here)
  • Put emphasis and on educating the public and businesses about and implementing reduce, re-use, recycle, and other key principles that deal with minimising waste, using materials and resources more efficiently, and proper waste management


Other solutions may include …


  • Money can often be saved with more efficiently designed collection routes, modifying vehicles, and with public education. Environmental policies such as pay as you throw can reduce the cost of management and reduce waste quantities. Waste recovery (that is, recycling, reuse) can curb economic costs because it avoids extracting raw materials and often cuts transportation costs
  • Separate and sort – separating and sorting out recyclable materials like paper, cardboard, metals and wood after receiving a delivery. Transporting, recycling, treating, and disposing of hazardous waste properly
  • Land is a precious commodity and by reducing the amount of waste we produce, reusing items more than once and recycling items correctly we can avoid the creation of more landfill sites and help maintain our unique environment. By recycling and removing all food and garden waste from our red-lidded general waste bin, landfill sites can be maintained for longer, helping to reduce biodiversity loss, save valuable space and reduce the amount of pests in our ecosystems



  • Ideally, we would like our plastic, glass, metal and paper waste to end up at a recycling facility. It then returns to us as a renewable product.



How different countries are trying to improve waste can be found at


  • Refuse – if you don’t really need it, don’t buy it. Or decline unnecessary carry bags.
  • Reduce – buy less and buy smarter. For example, Australians throw away about 30% of the food they purchase.
  • Reuse – take reusable bags when you go shopping or reuse ‘disposable’ bags.
  • Repair – don’t toss it, fix it. You may even save some money.
  • Repurpose – give an old item a new purpose and a new lease on life.
  • Resell (or donate) – if you no longer need it, someone else might have a use for it.
  • Recycle – when it finally fails and there is no other option, make sure it is recycled.
  • Rebuy – look for items that contain recycled materials to keep the system working.



  • Find ways to recycle more – currently, the U.S. recycles about 30% of its waste stream, even though the EPA estimates that up to 75% of our waste stream is recyclable. Only 1% of all plastic products in the United States are recycled every year, as are only 1% of all aluminum products. There are many benefits to recycling
  • Paper and cardboard – Paper and cardboard make up the majority of industrial waste products. This means that the average company can make a big impact simply by establishing a paper and cardboard recycling program. Businesses can have a huge impact on the environment, on our energy dependence, and on their own bottom line by taking steps to recycle more and landfill less. One of the simplest places to start is with a strong cardboard recycling program, as this is a valuable commodity that is easy to move.



According to Worldbank:

The World Bank finances and advises on solid waste management projects using a diverse suite of products and services, including traditional loans, results-based financing, development policy financing, and technical advisory.

World Bank-financed waste management projects address the entire lifecycle of waste—from generation to collection and transportation, and finally treatment and disposal.

Objectives that guide the Bank’s solid waste management projects and investments include:

  • Infrastructure: The World Bank provides capital investments to build or upgrade waste sorting and treatment facilities, close dumps, construct or refurbish landfills, and provide bins, dumpsters, trucks, and transfer stations.
  • Legal structures and institutions: Projects advise on sound policy measures and coordinated institutions for the municipal waste management sector.
  • Financial sustainability: Through the design of taxes and fee structures, and long-term planning, projects help governments improve waste cost containment and recovery.
  • Citizen engagement: Behavior change and public participation is key to a functional waste system. The World Bank supports designing incentives and awareness systems to motivate waste reduction, source-separation and reuse.
  • Social inclusion: Resource recovery in most developing countries relies heavily on informal workers, who collect, sort, and recycle 15%–20% of generated waste. Projects address waste picker livelihoods through strategies such as integration into the formal system, as well as the provision of safe working conditions, social safety nets, child labor restrictions, and education.
  • Climate change and the environment: Projects promote environmentally sound waste disposal. They support greenhouse gas mitigation through food loss and waste reduction, organic waste diversion, and the adoption of disposal technologies that capture biogas and landfill gas. Waste projects also support resilience by reducing waste disposal in waterways and safeguarding infrastructure against flooding.
  • Health and safety: The World Bank’s work in municipal waste management improves public health and livelihoods by reducing open burning, mitigating pest and disease vector spread, and preventing crime and violence.
  • Knowledge creation: The World Bank helps governments plan and explore locally appropriate solutions through technical expertise, and data and analytics.

The World Bank’s waste management engagement spans multiple development areas, including energy, environmental sustainability, food and agriculture, health and population, social protection, transportation, urban development, and water.

The World Bank has also documented the results of these solutions they have implemented



The 2100 forecast above in this guide is based on current rates of generation and disposal and consumption.

But that forecast can change:

“With lower populations, denser, more resource-efficient cities, and less consumption (along with higher affluence), the peak could come forward to 2075 and reduce in intensity by more than 25 percent. This would save around 2.6 million tonnes per day,” Hoornweg and his colleagues write.

Some cities are already setting positive examples for waste reduction. San Francisco, for example, has an ambitious goal of “zero waste” by 2020 with aggressive recycling. About 55 percent of its waste is recycled or reused today. Industries in Kawasaki, Japan, divert 565,000 tonnes of potential waste per year – exceeding the city’s current municipal waste levels.

Other tactics cities can embrace include:

  • Reducing food waste with better storage and transportation systems, which can both help lower trash levels and help feed a growing world population.
  • Construction strategies that reuse materials, saving trees and the energy that goes into developing other building materials and reducing waste.
  • Policies such as disposal fees and recycling programs that encourage less waste.

“The planet is already straining from the impacts of today’s waste and we are on a path to more than triple quantities,” the authors write. “Through a move towards stable or declining populations, denser and better-managed cities consuming fewer resources, and greater equity and use of technology, we can bring peak waste forward and down. The environmental, economic and social benefits would be enormous.”



More resources on potential solutions are:

  • (good resource on reducing business waste)


Other Areas Of Waste Generation & Pollution To Be Aware Of

The extent of waste and it’s impact is almost limitless. Just a FEW of the further points to be aware of might be (but there are many more):

  • Which sectors and waste materials produce the most waste that goes straight to landfill and can’t be re-used or recycled
  • What the most damaging wastes are (hazardous and toxic wastes are particularly damaging)
  • What the most damaging sectors and industries are
  • Look at the economic impact of waste, and the cost of different waste disposal methods. A guide outlining the value of the US waste industry can be found at According to, on average, it costs $30 per ton to recycle trash, $50 to send it to the landfill, and $65 to $75 to incinerate it.
  • Know that waste practices and behaviors are not the same among regions, countries, sectors and so on – each community and system is different












































Plastic Pollution (& Waste): Causes, Sources, Effects & Solutions

Plastic Pollution: Causes, Sources, Effects & Solutions

Plastic is a widely used material in society.

Although plastic has some important uses, plastic pollution is also an issue that can arise from its use.

Plastic pollution can have a significant impact on humans, animals, the natural environment, and even the economy.

In this guide we outline what plastic pollution is, the causes, the sources, the effects, and potential solutions to mitigate and reduce plastic pollution.

You can also read more generally about waste pollution in this guide 

(NOTE: we have heavily paraphrased in this guide. You can find their full articles here –, and here


Summary – Plastic Pollution

  • Plastic has a long list of pros and cons, and is a widely used material across a number of sectors
  • The way industrialized and even developing countries are currently set up, we probably couldn’t get by without plastic due to the number of important uses it has
  • However, the flip side of that, is that plastic also has a significant negative impact on society in a number of ways – and, this is something that needs to be addressed
  • The causes of plastic pollution stem firstly from how plastic is made and what it is made of, and then the sheer quantity of plastic we produce and use, along with how we manage and dispose of it
  • The sources of plastic pollution stem from certain types of plastic, and specific countries, regions, industries and businesses that are responsible for using, producing or mismanaging the most plastic
  • The effects of plastic pollution are wide ranging, from mining of petrochemicals to make plastics (and associated waste, water pollution, and other consequences of mining), the production process of plastic and it’s waste, leaching of chemicals from certain plastics, ingestion, entanglement, and abrasion by mismanaged plastic waste, the impact of plastic on humans and human health, and even the economy
  • There are many potential solutions to plastic pollution such as using plastic more effectively, finding ways to re-design and re use or recycle more plastic, finding alternative materials to use that are more natural and biodegradable or reusable, and targeting the specific sources of plastic that cause the most problems, such as types of plastic, and specific regions, countries, businesses and industries


What Is Plastic Pollution?

Plastic pollution has many definitions, but it could generally be defined as the ‘presence in or introduction into the environment of plastic which has harmful or poisonous effects’

Some people restrict these effects to the environment only, but in reality, plastic impacts humans, health, society and the economy on a wider and deeper level as well.


Causes Of Plastic Pollution

Some of the main causes of plastic pollution are:

  • The wide use of plastic in society, and the quantity of it that we produce and use … especially single use or short use plastic
  • The materials and chemicals that are required to make plastic – petrochemicals are used, and fossil fuels have to be mined
  • The manufacturing of plastic produces waste and can use harmful chemicals
  • What plastic is made of (it’s chemical make up) – it’s synthetic, unlike natural materials
  • How long plastic lasts/how durable it is – it can last forever without fully breaking down
  • The way plastic is disposed of – mismanaged and gets into rivers and the ocean, creates gases/emissions in landfill along with leachate, or gets burnt and releases pollutants (gasification and pyrolysis both have issues with using them at scale over waste to energy plants)
  • Plastic can only be recycled so many times before it has to be discarded


Sources Of Plastic Pollution

Some of the main sources of plastic pollution are:

  • Plastic packaging
  • Single use plastics
  • Toxic plastics
  • Non recyclable plastic
  • Recyclable plastic that isn’t actually recycled (and re-directed to landfill)
  • Countries and regions that use or produce the most plastic (and import from poor countries, or export it to countries like China to recycle – although China has since stopped taking plastic from other countries)
  • Countries and regions that are responsible for the most mismanaged plastic and ocean plastic
  • Industries that use the most plastic and produce the most plastic waste
  • Businesses and companies that use the most plastic and produce the most plastic waste


Effects Of Plastic Pollution

Plastic pollution can have an impact on all areas of society such as the environment (water, land, air), humans and human health, wildlife, and the economy.

Some specific effects of plastic pollution might be:

  • Plastic is made of petrochemicals – so it uses fossil fuels, and involves mining and fracking to source these base chemicals
  • The production process of plastic can involve emissions, as well as waste which is dumped into the environment
  • Mismanaged plastic gets into rivers, which is carried out to the ocean
  • Plastic in the environment leads to ingestion, entanglement, abrasion for animals and organisms of all sizes
  • Micro plastics are the result of bigger pieces of plastic breaking down into micro pieces of plastic – they can get into animals and organisms, and possibly into the food supply
  • Plastic releases toxic chemicals that can leach into the environment, into soil, into water sources, and even onto human tissue (which may have health related consequences for humans)
  • Chlorinated plastic specifically can release harmful chemicals (can seep into soil, groundwater and other water sources) 
  • Plastic sent to land fills can release emissions as well as leachate
  • Plastic recycling isn’t always cost of time efficient, and some plastic can’t be recycled (and may be sent to landfill)
  • Incineration waste to energy burning of plastic may release emissions or air contaminants. Gasification and pyrolysis, which may be less environmentally damaging, have some challenges preventing their large scale adoption at the moment
  • The economic cost to address plastic pollution in oceans and on land can be significant


Solutions To Plastic Pollution

Some of the main solutions to address plastic pollution might be:

  • Redesign plastic to contain more biodegradable, less toxic, and more natural materials (over petrochemicals)
  • Redesign plastic to be recyclable and re-usable and contribute to the
  • Redesign plastic to not break down into microplastics
  • Use alternative materials other than plastic
  • Use plastic far more wisely and effectively in lesser quantities and for longer lasting items (that lasts years and decades)
  • Target countries and regions that produce or use the most plastic
  • Target countries and regions that mismanage and poorly dispose of plastic the most
  • Target countries that burn the most plastic and emit the most air pollution and greenhouse gases
  • Target countries and regions that are responsible for the most plastic waste in the ocean
  • Target organizations and businesses in addition to countries and regions
  • Overall, we need to be aware of the cons of using the different types of plastic, and the negative short and long term consequences, and we have to balance that against the pros that plastic provides. We have to look at all areas of society – the social and health, environmental, and economic areas.


More Resources & Guides On Plastic, & Plastic Pollution



1. Hannah Ritchie and Max Roser (2018) – “Plastic Pollution”. Published online at Retrieved from: ‘’ [Online Resource]








What Elon Musk Said On The Joe Rogan Experience About Climate Change, Carbon Emissions, Sustainable Energy & Electric Cars

Elon Musk was on the Joe Rogan Experience today, and they covered some important topics such as Climate Change, Carbon Emissions, Sustainable Energy, Electric Cars and much more.

The following are some interesting paraphrased quotes from Elon Mush on the Joe Rogan Experience on Thursday 6th September, 2018:


Electric cars are important, solar energy is important, stationary storage of energy is important


It’s important that we accelerate the transition to sustainable energy. That’s why electric cars matter, whether electric cars happen sooner or later


We’re really playing a crazy game here with the atmosphere and the oceans. We’re taking vast amounts of carbon from deep underground, and putting this in the atmosphere – this is crazy! We should not do this. It’s very dangerous


The bizarre thing is that we are going to run out of oil long term. There’s only so much oil we can mine and burn. We must have a sustainable energy transport and infrastructure in the long term – we know that’s the end point. We know that. So, why run this crazy experiment, where we take trillions of tonnes of carbon from underground, and put it in the atmosphere and oceans. This is an insane experiment. This is the dumbest experiment in human history. Why are we doing this…it’s crazy!


The thing is – oil, coal, gas…it’s easy money.


It’s very difficult to put C02 back in the ground, it doesn’t like being in solid form, it takes a lot of energy[in answer to Joe Rogan’s questioning about clean coal].


The more carbon we take out of the ground, and it gets added to the atmosphere, and a lot of it gets permeated into the oceans, the more dangerous it is. I think we are OK right now…we can probably even add some more. But, the momentum towards sustainable energy is too slow.


There’s a vast base of industry, vast transportation industry. There’s 2.5 billion cars and trucks in the world. And new car and truck production – if it was 100% electric, that’s only about 100 million per year [new cars and trucks produced]. So, if you could snap your fingers, and turn all cars and trucks electric, it would still take 25 years, to change the transport base to electric. Make sense? Because how long does it take for a car or truck to go into the junk yard and get crushed? About 20-25 years.


[Joe asks – is there a way to accelerate the electric vehicle transition process – via subsidies, or encouragement from the government for example] Elon says – the thing is, what is going on now is there is an inherent subsidy in any oil burning device, any power plant or car, is fundamentally consuming the carbon capacity of the oceans and atmosphere…or just say atmosphere for short.


So, you can say there is a certain probability of something bad happening past a certain carbon concentration in the atmosphere. And, so there’s some uncertain number where if we put too much carbon in the atmosphere, things overheat, oceans warm up, ice caps melt, ocean real estate becomes a lot less valuable…because it’s underwater. It’s not clear what that number is, but the scientific consensus is overwhelming.


I don’t know any serious scientist, in fact, quite literally zero, that don’t think that there’s a quite serious climate risk that we’re facing


There’s fundamentally a subsidy occurring with every fossil fuel burning thing – power plants, aircrafts, cars, even rockets.


With cars there’s definitely a better way – with electric cars, to generate the energy with photovoltaics. Because, we’ve got a giant thermonuclear reactor in the sky called the Sun – it’s great, it shows up every day, it’s very reliable. You can generate energy with solar panels, store it with batteries 24 hours a day. And then you can send it to the Poles, to the North, with high voltage lines. The Northern parts of the world tend to have a lot of hydropower as well.


Anyway, all fossil fuel powered things have an inherent subsidy, which is their consumption of the carbon capacity of the atmosphere, and oceans.


People tend to think – why should electric vehicles have a subsidy? But, they aren’t taking into account that all fossil fuel burning vehicles have a subsidy which is the environmental cost to earth…but, nobody is paying for it. We will all pay for it in the future though eventually. It’s just not paid for now.


[Joe asks what the bottleneck is with electric cars – is it battery capacity?] Elon says we have to scale up production, we have to make the car compelling, make it better than gasoline or diesel cars, make it go far enough, make it go fast.


[Joe asks what Elon sees when he thinks about the future of his companies – what he sees as bottlenecks to holding back innovation] Elon says that’s a good question, but he wishes politicians were better at science – that would help a lot. [Joe says that’s a problem – there’s no incentive for them to be good at science]. Elon agrees but says they are pretty good at science in China. The mayor of Beijing he believes has an environmental engineering degree and the deputy mayor has a physics degree. The mayor of Shanghai is really smart.


Water Scarcity: Causes, Effects, Solutions, Forecasts & Stats

Water Scarcity: Causes, Effects, Solutions & Stats

Water scarcity is made up of a number of water related factors and issues.

It is a term loosely thrown around by different organisations and media outlets, with different meanings depending on who is using it and in what context.

In this guide we outline what water scarcity is, the types of water scarcity, what causes it, the effects, countries affected, and solutions.


Summary – Water Scarcity

  • Water scarcity is a different measurement and indicator to water stress
  • Water stress is simply an indicator of water supplies vs water demand – expressed as low to high levels of water stress
  • Water scarcity occurs when water demand actually exceeds internal water resources i.e. a water stressed country or city is more likely to experience water scarcity
  • There’s a range of potential ways to measure water scarcity
  • There’s a range of types of water scarcity such as physical water scarcity, and economic water scarcity
  • Causes of water scarcity can vary, but could be a combination of any of the following overpopulation or a growth in population, lack of signifiacant/adequate freshwater supplies, lack of money to invest in tech and infrastructure used for accessing and maintaining freshwater, poor management of water resources or access to water resources, high usage/demand and increased consumption of water in all sectors (residential, commercial, industrial) and particularly agriculture, high temperatures and dry climates, climate change, droughts, lack of rainfall, or variability in rainfall, and natural events and natural disasters like floods which pollute or disrupt a water supply
  • One-third of the global population (2 billion people) live under conditions of severe water scarcity at least 1 month of the year
  • Half a billion people in the world face severe water scarcity all year round
  • Half of the world’s largest cities experience water scarcity
  • Water Demand is expected to outstrip supply by 40% in 2030, if current trends continue.
  • Scarcity can be expected to intensify with most forms of economic development, but, if correctly identified, many of its causes can be predicted, avoided or mitigated
  • Desalination plants and recycling and re-using grey water and waste water after treatment are just some of the options in developed countries to combat water scarcity
  • In developing countries, financial investment to address water pollution and contamination, human waste and treatment and hygiene infrastructure, fresh water supply etc. are required


What Is Water Scarcity, & Absolute Water Scarcity?

  • Water scarcity is the lack of fresh water resources to meet water demand.
  • The essence of global water scarcity is the geographic and temporal mismatch between freshwater demand and availability.


  • Water scarcity is more extreme than water stress, and occurs when water demand exceeds internal water resources.



Note that there is a difference between water scarcity, and absolute water scarcity – which we outline below.

Keep this in mind when you read stats about water scarcity.


Measuring Water Scarcity explains that there are 4 ways water scarcity might be measured and described:

1. One of the most commonly used measures of water scarcity is the ‘Falkenmark indicator’ or ‘water stress index’. This method defines water scarcity in terms of the total water resources that are available to the population of a region; measuring scarcity as the amount of renewable freshwater that is available for each person each year.

If the amount of renewable water in a country is below 1,700 m3 per person per year, that country is said to be experiencing water stress; below 1,000 m3 it is said to be experiencing water scarcity; and below 500 m3, absolute water scarcity.


2. An alternative way of defining and measuring water scarcity is to use a criticality ratio. This approach relaxes the assumption that all countries use the same amount of water, instead defining water scarcity in terms of each country’s water demand compared to the amount of water available; measuring scarcity as the proportion of total annual water withdrawals relative to total available water resources.

Using this approach, a country is said to be water scarce if annual withdrawals are between 20-40% of annual supply, and severely water scarce if they exceed 40%.


3. A third measure of water scarcity was developed by the International Water Management Institute (IWMI). This approach attempts to solve the problems listed above by including: each country’s water infrastructure, such as water in desalination plants, into the measure of water availability; including recycled water by limiting measurements of water demand to consumptive use rather than total withdrawals; and measuring the adaptive capacity of a country by assessing its potential for infrastructure development and efficiency improvements.

Using this approach, the IWMI classifies countries that are predicted to be unable to meet their future water demand without investment in water infrastructure and efficiency as economically water scarce; and countries predicted to be unable to meet their future demand, even with such investment, as physically water scarce.


4. A fourth approach to measuring water scarcity is the ‘water poverty index’. This approach attempts to take into account the role of income and wealth in determining water scarcity by measuring: (1) the level of access to water; (2) water quantity, quality, and variability; (3) water used for domestic, food, and productive purposes; (4) capacity for water management; and (5) environmental aspects. The complexity of this approach, however, means that it is more suited for analysis at a local scale, where data is more readily available, than on a national level.


You can read more about each approach and it’s limitations in’s guide.


Water Scarcity vs Water Stress

Water stress is the ratio of total withdrawals to total renewable supply in a given area. A higher percentage means more water users are competing for limited water supplies, and therefore that area/country is more stressed.

But water stress is just an indicator how how close a country might be getting to running out of water.

(You can read more about water stress and water stress related information in this guide)

On the other hand, a country is water scarce when water is not available to meet demand.


Types Of Water Scarcity

There’s two types of water scarcity:

Physical Water Scarcity

  • Results from inadequate natural water resources to supply a region’s demand
  • Around one fifth of the world’s population currently live in regions affected by Physical Water Scarcity, where there is inadequate water resources to meet a country’s or regional demand, including the water needed to fulfill the demand of ecosystems to function effectively.
  • It also occurs where water seems abundant but where resources are over-committed, such as when there is over development of hydraulic infrastructure for irrigation. Symptoms of physical water scarcity include environmental degradation and declining groundwater as well as other forms of exploitation or overuse.


  • can mean scarcity in availability due to physical shortage



Economic Water Scarcity

  • Can result in two ways…
  • Results from poor management of the sufficient available water resources
  • Or, results by a lack of investment in infrastructure or technology to draw water from rivers, aquifers or other water sources, or insufficient human capacity to satisfy the demand for water.
  • Found more often to be the cause of countries or regions experiencing water scarcity, as most countries or regions have enough water to meet household, industrial, agricultural, and environmental needs, but lack the means to provide it in an accessible manner.
  • One quarter of the world’s population is affected by economic water scarcity.
  • Economic water scarcity includes a lack of infrastructure, causing the people without reliable access to water to have to travel long distances to fetch water, that is often contaminated from rivers for domestic and agricultural uses.
  • Large parts of Africa suffer from economic water scarcity; developing water infrastructure in those areas could therefore help to reduce poverty.
  • Critical conditions often arise for economically poor and politically weak communities living in already dry environment.
  • Consumption increases with GDP per capita in most developed countries, and the average amount (per capita) is around 200–300 litres daily.
  • In underdeveloped countries (e.g. African countries such as Mozambique), average daily water consumption per capita was below 10 L.
  • This is against the backdrop of international organisations, which recommend a minimum of 20 L of water (not including the water needed for washing clothes), available at most 1 km from the household.
  • Increased water consumption is correlated with increasing income, as measured by GDP per capita. In countries suffering from water shortages water is the subject of speculation.


  • can mean scarcity in access due to the failure of institutions to ensure a regular supply, or
  • scarcity due to a lack of adequate infrastructure



What Causes Water Scarcity?

There’s many factors that can cause water scarcity including:

  • Overpopulation or a growth in population
  • Lack of freshwater reserves
  • Lack of money to invest in tech and infrastructure used for accessing freshwater
  • Poor management of water resources or access to water resources
  • High usage/demand and increased consumption of water in all sectors (residential, commercial, industrial) and particularly agriculture
  • High temperatures and dry climates
  • Climate change
  • Droughts
  • Lack of rainfall, or variability in rainfall
  • Natural events and natural disasters like floods which pollute or disrupt a water supply also offers other causes:

  • Partial or no satisfaction of expressed demand
  • Economic competition for water quantity or quality
  • Disputes between users of water sources
  • Irreversible depletion of groundwater
  • Negative impacts on the environment which impact water sources
  • Technically, there is a sufficient amount of freshwater on a global scale. However, due to unequal distribution (exacerbated by climate change) resulting in some very wet and some very dry geographic locations, plus a sharp rise in global freshwater demand in recent decades driven by industry, humanity is facing a water crisis.
  • The increasing world population, improving living standards, changing consumption patterns, and expansion of irrigated agriculture are the main driving forces for the rising global demand for water.
  • Climate change, such as altered weather-patterns (including droughts or floods), deforestation, increased pollution, green house gases, and wasteful use of water can cause insufficient supply
  • At the global level and on an annual basis, enough freshwater is available to meet such demand, but spatial and temporal variations of water demand and availability are large, leading to (physical) water scarcity in several parts of the world during specific times of the year. All causes of water scarcity are related to human interference with the water cycle. Scarcity varies over time as a result of natural hydrological variability, but varies even more so as a function of prevailing economic policy, planning and management approaches.
  • The total amount of easily accessible freshwater on Earth, in the form of surface water (rivers and lakes) or groundwater (in aquifers, for example), is 14.000 cubic kilometres (nearly 3359 cubic miles). Of this total amount, ‘just’ 5.000 cubic kilometres are being used and reused by humanity. Hence, in theory, there is more than enough freshwater available to meet the demands of the current world population of 7 billion people, and even support population growth to 9 billion or more. Due to the unequal geographical distribution and especially the unequal consumption of water, however, it is a scarce resource in some parts of the world and for some parts of the population.
  • Scarcity as a result of consumption is caused primarily by the extensive use of water in agriculture/livestock breeding and industry. People in developed countries generally use about 10 times more water daily than those in developing countries. A large part of this is indirect use in water-intensive agricultural and industrial production processes of consumer goods, such as fruit, oil seed crops and cotton. Because many of these production chains have been globalised, a lot of water in developing countries is being used and polluted in order to produce goods destined for consumption in developed countries.



Climate change and bio-energy demands are also expected to amplify the already complex relationship between world development and water demand



Effects Of Water Scarcity

The effects of water scarcity may not be so severe, but it can turn into absolute water scarcity if not managed properly.

Absolute water scarcity on the other hand can be detrimental to country or region. Some effects can involve:

  • Economic effects – lack of economic growth, and increased poverty
  • Health effects – malnutrition from lack of water and lack of water to grow food to eat, hygiene and sanitary related health issues
  • Environment effects – increased salinity, nutrient pollution, and the loss of floodplains and wetlands. Furthermore, water scarcity makes flow management in the rehabilitation of urban streams problematic.

There can also be flow on social impact from these effects such as threats to social health (diseases), safety (increased violence and war) and stability (loss of employment).

Humans, animals, plants and the greater natural environment and atmosphere can be impacted by scarcity of water.


How Much Of The World Is Affected By Water Scarcity?

  • One-third of the global population (2 billion people) live under conditions of severe water scarcity at least 1 month of the year
  • Half a billion people in the world face severe water scarcity all year round
  • Half of the world’s largest cities experience water scarcity


  • a total of 2.7 billion find water scarce for at least one month of the year



What’s The Future Forecast/Trend For Water Scarcity?

  • Water Demand is expected to outstrip supply by 40% in 2030, if current trends continue.
  • Scarcity can be expected to intensify with most forms of economic development, but, if correctly identified, many of its causes can be predicted, avoided or mitigated



Solutions To Water Scarcity

General solutions to water scarcity may include:

  • Getting access to additional freshwater sources
  • Investing in water technology and infrastructure in low income, and highly water stressed countries and regions
  • Controlling populations in human dense cities and urban locations
  • Controlling water pollution
  • Using water efficiently at the home, commercial and industrial levels
  • Governments having good water management plans now and in the future, and governments being more organised
  • Developing freshwater technology to be cheaper and more energy friendly e.g. desalination plants
  • Mitigating the impact of climate change
  • Having drought and other natural event management plans
  • Better co-operation between countries on shared or trans-boundary freshwater sources
  • Everyone in society treating water as a scare resource to be protected
  • + more


More specific solutions, per, may include:

  • Some countries have already proven that decoupling water use from economic growth is possible. For example, in Australia, water consumption declined by 40% between 2001 and 2009 while the economy grew by more than 30%. The International Resource Panel of the UN states that governments have tended to invest heavily in largely inefficient solutions: mega-projects like dams, canals, aqueducts, pipelines and water reservoirs, which are generally neither environmentally sustainable nor economically viable. The most cost-effective way of decoupling water use from economic growth, according to the scientific panel, is for governments to create holistic water management plans that take into account the entire water cycle: from source to distribution, economic use, treatment, recycling, reuse and return to the environment.
  • Construction of wastewater treatment plants and reduction of groundwater overdrafting appear to be obvious solutions to the worldwide problem; however, a deeper look reveals more fundamental issues in play.
  • Wastewater treatment is highly capital intensive, restricting access to this technology in some regions; furthermore the rapid increase in population of many countries makes this a race that is difficult to win.
  • As if those factors are not daunting enough, one must consider the enormous costs and skill sets involved to maintain wastewater treatment plants even if they are successfully developed.
  • Reducing groundwater overdrafting is usually politically unpopular, and can have major economic impacts on farmers. Moreover, this strategy necessarily reduces crop output, something the world can ill-afford given the current population.
  • At more realistic levels, developing countries can strive to achieve primary wastewater treatment or secure septic systems, and carefully analyse wastewater outfall design to minimize impacts to drinking water and to ecosystems. Developed countries can not only share technology better, including cost-effective wastewater and water treatment systems but also in hydrological transport modeling. At the individual level, people in developed countries can look inward and reduce over consumption, which further strains worldwide water consumption.
  • Both developed and developing countries can increase protection of ecosystems, especially wetlands and riparian zones. There measures will not only conserve biota, but also render more effective the natural water cycle flushing and transport that make water systems more healthy for humans.
  • A range of local, low-tech solutions are being pursued by a number of companies. These efforts center around the use of solar power to distill water at temperatures slightly beneath that at which water boils. By developing the capability to purify any available water source, local business models could be built around the new technologies, accelerating their uptake. For example, Bedouins from the town of Dahab in Egypt have installed Aqua Danial’s Water Stellar, which uses a solar thermal collector measuring two square meters to distill from 40 to 60 liters per day from any local water source.
  • This is five times more efficient than conventional stills and eliminates the need for polluting plastic PET bottles or transportation of water supply.



There is not a global water shortage as such, but individual countries and regions need to urgently tackle the critical problems presented by water stress.

Water has to be treated as a scarce resource, with a far stronger focus on managing demand. Integrated water resources management provides a broad framework for governments to align water use patterns with the needs and demands of different users, including the environment.



Stats On Water Scarcity

  • Around 1.2 billion people, or almost one-fifth of the world’s population, live in areas of scarcity. Another 1.6 billion people, or almost one quarter of the world’s population, face economic water shortage (where countries lack the necessary infrastructure to take water from rivers and aquifers). (FAO, 2007) via
  • Around 700 million people in 43 countries suffer today from water scarcity. (Global Water Institute, 2013)
  • Two thirds of the world’s population currently live in areas that experience water scarcity for at least one month a year. (Mekonnen and Hoekstra, 2016) via
  • By 2025, 1.8 billion people are expected to be living in countries or regions with absolute water scarcity, and two-thirds of the world population could be under water stress conditions. (UNESCO, 2012) via
  • With the existing climate change scenario, by 2030, water scarcity in some arid and semi-arid places will displace between 24 million and 700 million people. (UNCCD) via
  • A third of the world’s biggest groundwater systems are already in distress (Richey et al., 2015) via
  • Nearly half the global population are already living in potential waterscarce areas at least one month per year and this could increase to some 4.8–5.7 billion in 2050. About 73% of the affected people live in Asia (69% by 2050) (Burek et al., 2016) via







5. Hannah Ritchie and Max Roser (2018) – “Water Access, Resources & Sanitation”. Published online at Retrieved from: ‘’ [Online Resource]


Water Stress: Causes, Effects, Solutions, Forecast & Stats

Water Stress: Causes, Effects, Solutions & Stats

Water stress is tightly linked to other global water issues.

The reason it is important to know about and keep track of is, the more water stressed a country or region gets, the closer they get to a water shortage.

In this guide we look at what it is, what causes it, the effect it has, potential solutions, as well as other important stats and information about water stress.


Summary – Water Stress

  • Water stress can be an indication of how much pressure a city’s fresh water supplies are under, and how close they are to being depleted. Water stress can be measured in cubic meters of fresh water remaining per person, per year. The lower the measurement get, the more water stressed a region becomes
  • Causes of high water stress can include lack of natural or standard freshwater reserves, High water usage/demand and increased consumption of water in all sectors (residential, commercial, industrial) and particularly agriculture, population growth or high population density (like in big cities), high temperatures and dry climates, increasing temperatures, droughts, lack of rainfall, or variability in rainfall, and natural events and natural disasters like floods which pollute or disrupt a water supply
  • More than one in every six people in the world is water stressed, meaning that they do not have sufficient access to potable water.
  • Some estimates predict that by 2040, around 33 countries could face extreme water stress
  • Governments implementing short term and long term water conservation and water supply policies and actions are KEY to preventing water stress in the future – especially in dry, warm, low rainfall, drought prone cities with growing populations


What Is Water Stress?

A few different definitions and explanations of water stress are:

– Water stress is the ratio of total withdrawals to total renewable supply in a given area. A higher percentage means more water users are competing for limited water supplies, and therefore that area/country is more stressed –

– Water stress is defined based on the ratio of freshwater withdrawals to renewable freshwater resources. Water stress does not insinuate that a country has water shortages, but does give an indication of how close it maybe be to exceeding a water basin’s renewable resources. If water withdrawals exceed available resources (i.e. greater than 100 percent) then a country is either extracting beyond the rate at which aquifers can be replenished, or has very high levels of desalinisation water generation (the conversion of seawater to freshwater using osmosis processes). –

– According to the Falkenmark Water Stress Indicator, a country or region is said to experience “water stress” when annual water supplies drop below 1,700 cubic metres per person per year. At levels between 1,700 and 1,000 cubic meters per person per year, periodic or limited water shortages can be expected. When a country is below 1,000 cubic meters per person per year, the country then faces water scarcity . –


Water Stress Ratings & Scale

According to the WRI, countries can fit into the following ranges, based on ratio of water withdrawals to water supply in the country:

  • Low – less than 10% (i.e. the country is withdrawing less than 10% of their overall water supply)
  • Low To Medium – 10 to 20%
  • Medium To High – 20 to 40%
  • High – 40 to 80%
  • Extremely High – more than 80%

So, a country withdrawing more than 80% of their water supply would be classified as having extremely high water stress.



Causes Of Water Stress

It differs depending on the country. But general factors can include:

  • Lack of freshwater reserves
  • High usage/demand and increased consumption of water in all sectors (residential, commercial, industrial) and particularly agriculture
  • Population growth
  • High temperatures and dry climates
  • Climate change
  • Droughts
  • Lack of rainfall, or variability in rainfall
  • Natural events and natural disasters like floods which pollute or disrupt a water supply


Some of the other factors can include:

  • Rapidly growing populations will drive increased consumption by people, farms and companies
  • More people will move to cities, further straining supplies
  • An emerging middle class could clamor for more water-intensive food production and electricity generation



  • Another popular opinion is that the amount of available freshwater is decreasing because of climate change.



  • Every water-stressed country is affected by a different combination of factors. Chile, for example, projected to move from medium water stress in 2010 to extremely high stress in 2040, is among the countries more likely to face a water supply decrease from the combined effects of rising temperatures in critical regions and shifting precipitation patterns.
  • Botswana and Namibia sit squarely within a region that is already vulnerable to climate change. Water supplies are limited, and risk from floods and droughts is high. Projected temperature increases in southern Africa are likely to exceed the global average, along with overall drying and increased rainfall variability. On the water demand side, according to Aqueduct projections, a 40 to 70 percent—or greater—increase is expected, further exacerbating the region’s concerns.
  • Whatever the drivers, extremely high water stress creates an environment in which companies, farms and residents are highly dependent on limited amounts of water and vulnerable to the slightest change in supply. Such situations severely threaten national water security and economic growth.



  • By 2030, water demand is expected to exceed current supply by 40 percent, according to the Water Resources Group, an arm of the World Bank.
  • “In many parts of the world, water scarcity is increasing and rates of growth in agricultural production have been slowing,” United Nations Secretary-General Ban Ki-moon said in an address to mark World Water Day last month.
  • “At the same time, climate change is exacerbating risk and unpredictability for farmers, especially for poor farmers in low-income countries…These interlinked challenges are increasing competition between communities and countries for scarce water resources, aggravating old security dilemmas, creating new ones and hampering the achievement of the fundamental human rights to food, water and sanitation.”
  • Experts say water shortages aren’t solely about a planetary climate that is becoming warmer and drier. Much of the blame can also be laid on the mismanagement of existing water resources.
  • Many industrial processes use a staggering amount of water from start to finish. It takes about 270 gallons of water to produce $1 worth of sugar; 200 gallons of water to make $1 worth of pet food; and 140 gallons of water to make $1 worth of milk.

–, and


Effects Of Water Stress

Overall, higher water stress means freshwater reserves are being depleted, and the closer you get to very high water stress, the closer you get to a water shortage.

Water restrictions means there is less water for all activities in the residential, commercial and industrial sectors.

Water shortages means extreme restrictions on water, and in some cases no water is available either temporarily or permanently for a certain period of time.

There are negative social, economic, health and environmental effects because of this.

Agriculture, as a big user of water, has less water to grow food for the population. Other businesses also have less water for products and raw materials manufacture.

There may also be less drinking water, water for sanitation, and water for cleaning for households – all of which can effect health and hygiene.


Other effects can be:

  • Businesses, farms, and communities in countries affected by water stress in particular may be more vulnerable to water scarcity
  • Civil wars can break out in extreme circumstances
  • Dwindling water resources and chronic mismanagement forced 1.5 million people, primarily farmers and herders, to lose their livelihoods and leave their land, move to urban areas, and magnify Syria’s general destabilization.



How Much Of The World Is Affected By Water Stress

  • More than one in every six people in the world is water stressed, meaning that they do not have sufficient access to potable water.
  • Those that are water stressed make up 1.1 billion people in the world and are living in developing countries.
  • In 2006, about 700 million people in 43 countries were living below the 1,700 cubic metres of water per person, per year threshold.



Countries That Are Water Stressed

  • Water stress is ever intensifying in regions such as China, India, and Sub-Saharan Africa, which contains the largest number of water stressed countries of any region with almost one fourth of the population living in a water stressed country.
  • The world’s most water stressed region is the Middle East with averages of 1,200 cubic metres of water per person.
  • In China, more than 538 million people are living in a water-stressed region.
  • Much of the water stressed population currently live in river basins where the usage of water resources greatly exceed the renewal of the water source.



Forecasts & Trends For Water Stress Now & In The Future

Estimates have been done for 167 countries by 2040

WRI scored and ranked future water stress—a measure of competition and depletion of surface water—in 167 countries by 2020, 2030, and 2040. They found that 33 countries face extremely high water stress in 2040

It was found that Chile, Estonia, Namibia, and Botswana could face an especially significant increase in water stress by 2040. This means that businesses, farms, and communities in these countries in particular may be more vulnerable to scarcity than they are today.


You can check out for the forecast of water stressed countries by 2040, and a handy map which shows the forecasted water stress level of these countries.


Solutions To Water Stress

  • National and local governments must bring forward strong national climate action plans and support a strong international climate agreement
  • Governments must also respond with management and conservation practices that will help protect essential sustainable water resources for years to come.



  • In Australia, water consumption declined by 40% between 2001 and 2009 while the economy grew by more than 30%. The International Resource Panel of the UN states that governments have tended to invest heavily in largely inefficient solutions: mega-projects like dams, canals, aqueducts, pipelines and water reservoirs, which are generally neither environmentally sustainable nor economically viable. The most cost-effective way of decoupling water use from economic growth, according to the scientific panel, is for governments to create holistic water management plans that take into account the entire water cycle: from source to distribution, economic use, treatment, recycling, reuse and return to the environment.



  • Water reuse however poses some unique challenges. Strict water regulations, while providing necessary legislation around delivery of potable water to our homes, can create unnecessary barriers in use of wastewater for industry. Effluent water, known as ‘greywater’, is generated through wastewater municipal treatment plants, treated and discharged. Yet over 95% of grey water is simply discharged into surface ponds.
  • However greywater can provide a valuable opportunity for water reuse in non-potable applications within industry. Addressing regulatory standards would not only allow for efficient reuse of this greywater but reduce the burden on freshwater supplies. This policy has already shown great success in Singapore. Their Bedok NEWater reuse plant provides wastewater for industry, using GE’s ZeeWeed membrane technology to reliably remove suspended solids from water. Initiatives like this are why Singapore now boasts production of more than 100 million gallons a day of recycled water for industrial, commercial and domestic use.
  • Water reuse is not limited to a national scale. At Frito Lay’s Casa Grande facility, Arizona, they utilise a ZeeWeed membrane bioreactor and reverse osmosis system from GE that treats and recycles 648,000 gallons per day. This solution helped achieve ambitious renewable targets, including a 90% reduction in water and electricity usage. The plant has the distinction of being the first existing food manufacturing site in the United States to achieve LEED EB environmental Gold Certification.
  • Water reuse has also shown impressive benefits within the oil and gas industry. In 2015 the Carigali-PTTEPI Operating Company was honoured with an ecomagination award by General Electric, recognising its positive environmental impact for its success in water reuse on a natural gas platform in the Gulf of Thailand. By installing advanced GE cooling and chemical treatment technology the company were able to save 132,000 gallons of water and $52 million a year by reducing platform downtime.





2. .


4. Hannah Ritchie and Max Roser (2018) – “Water Access, Resources & Sanitation”. Published online at Retrieved from: ‘’ [Online Resource]




Best (& Most Effective) Ways To Reduce Your Own Personal Carbon Footprint

Best (& Most Effective) Ways To Reduce Your Carbon Footprint

You’ve probably read a few of these ‘reduce your carbon footprint’ guides before … and, so have we.

But, did you know that some guides might be giving you only the ‘low impact’ ways to reduce your footprint?

There’s been research done into what the best ways to reduce your carbon footprint are, and the approximate CO2e (kg of carbon dioxide equivalent) reduced per year by implementing these actions.

What was found was that there’s a clear difference between ‘high impact’, ‘moderate impact’ and ‘low impact’ actions.

It makes sense to seriously consider the high impact actions on an individual level, and through society as a whole.


Summary – Most Effective Ways To Reduce Personal Carbon Footprint

Some of the high impact ways listed below include:

  • Think about the number of children you have – each extra person in the world introduces new carbon emissions to the world
  • Think about how much you use your car, and consider how you can walk or ride around more (or catch public transport) – cars/individual conventional fuelled cars contribute to a lot of carbon emissions because they burn fossil fuels
  • Think about how often you fly in planes – taking less plane trips a year can reduce carbon emissions
  • Switch to renewable/green energy – if your house currently runs on coal or gas power, switching to solar or another renewable energy technology reduces emissions
  • Consider how you drive – buying a fuel efficient car, buying an electric car, or simply reducing the amount of braking and accelerating you do can all reduce emissions
  • Consider what your food diet looks like – meat, animals based products and processed foods all tend to have a high carbon footprint than plant based diets. It’s also worth noting that the highest offending carbon footprint meats tend to be beef, lamb, and pork, with chicken usually having a smaller carbon footprint


High Impact, Moderate Impact, & Low Impact Actions For Reducing Carbon Dioxide Emission Footprint

Seth Wynes and Kimberly Nicholas outline high impact, moderate impact and low impact ways to reduce carbon dioxide in terms of approximate CO2e reduced per year (in kg):

High Impact Actions

  • Have one fewer child – 23, 700 up to 117,  700 CO2e reduced per year (kg)
  • Live car free – 1000 up to 5300
  • Avoid one long range flight per year – 700 up to 2800
  • Purchase green energy – less than 100, up to 2500
  • Reduce effects of driving – 1190
  • Eat a plant based diet – 300 up to 1600

Moderate Impact Actions

  • Better home heating/cooling efficiency – 180
  • Install solar panels/renewable energy
  • Use public transportation, ride a bike, or walk
  • Buy energy efficient products
  • Conserve energy – 210
  • Reduce food waste – 370
  • Eat less meat – 230
  • Reduce consumption in general (of products)
  • Reuse – 5
  • Recycle – 210
  • Eat local – 0 up to 360

Low Impact Actions

  • Conserve water
  • Eliminate unnecessary travel
  • Minimize waste
  • Plant a tree – 6 up to 60
  • Compost
  • Purchase carbon offsets
  • Reduce lawn mowing
  • Eco tourism
  • Keep backyard chickens
  • Buy Eco labelled products
  • Calculate your home’s carbon footprint

Civic Actions

  • Spread awareness
  • Influence employer’s actions
  • Influence school’s actions

–, and

You can read more on their analysis into the climate mitigation gap at:



Further Solutions On Climate Change & Greenhouse Gas Emissions

We’ve also put together a guide on potential solutions for climate change and greenhouse gas emissions based issues, effects and impacts.

You might get some more ideas and insight into the issue by reading it.





Solutions To (& Options To Address) Climate Change & Greenhouse Gas Emissions

Solutions To Climate Change & Greenhouse Gas Emissions


The ideal goal for carbon emissions worldwide is to limit future warming to below a total increase of 2 degrees Celsius (which puts us in line with pre industrial revolution levels).

Whether we reach this goal or not is dependent on how aggressively we put in place and act on climate change and greenhouse gas emission solutions.

We look at some of these potential solutions below.

(*Note that no solution works on it’s own and no solution is completely perfect. It takes a comprehensive  and holistic approach with different solutions working together to reduce the effects of climate change)


Solutions To Climate Change & Greenhouse Gas Emissions – Summary

The one thing humans can control with climate change is the level of greenhouse gas emissions we emit in the future – we can reduce, or eliminate them altogether (bring emissions to zero).

The main causes behind human emissions of greenhouse gases (mainly carbon dioxide) is the burning of fossil fuels (coal, natural gas and oil) for:

  • electricity and heat production
  • transportation
  • industry (factories and production of goods and raw materials)
  • commercial and residential uses
  • and agriculture and clearing of land

The main approach to addressing these causes is:

  • Climate change mitigation – involves reducing or eliminating emissions, or creating carbon ‘sinks’ (absorbing carbon from the atmosphere)

Other approaches to addressing climate change are climate change adaptation, and climate engineering.


According to, we have 4 options:

  • Emissions reduction: reducing climate change by reducing greenhouse gas emissions.
  • Sequestration: removing carbon dioxide (CO2) from the atmosphere into permanent geological, biological or oceanic reservoirs.
  • Adaptation: responding to and coping with climate change as it occurs, in either a planned or unplanned way.
  • Solar geoengineering: large-scale engineered modifications to limit the amount of sunlight reaching the earth, in an attempt to offset the effects of ongoing greenhouse gas emissions.

Each embodies a large suite of specific options, with associated risks, costs and benefits. The four strategies can affect each other: for example, doing nothing to reduce emissions would require increased expenditure to adapt to climate change, and increased chances of future resort to geoengineering.


There are many ways to reduce emissions of CO2 and other warming agents, including shifting energy supply away from dependence on fossil fuels; energy efficiency in the domestic, industrial, service and transport sectors; reductions in overall demand through better system design; and efficient reductions in emissions of methane, nitrous oxide, halocarbon gases and black-carbon aerosols. Uptake of all of these options is happening now, and multiple studies have shown that they can be expanded effectively.

Ultimately, some climate change is inevitable and adaptation will definitely be required.

The more CO2 that is emitted in the next few decades, the stronger the adaptation measures that will be needed in future. There are limits to the adaptive capacities of both ecosystems and human societies, particularly in less developed regions. Thus, the decisions we make today on emissions will affect not only the future requirements for and costs of adaptation measures, but also their feasibility.



Solutions To Climate Change & Greenhouse Gas Emissions – Specific Examples




Commercial and Residential

Agriculture, Land Use and Forestry



Other Ideas and potential solutions from various sources might include…


Seth Wynes and Kimberly Nicholas outline high impact, moderate impact and low impact ways to reduce carbon dioxide in terms of approximate CO2e reduced per year (kg):

High Impact Actions

  • Have one fewer child – 23 700 up to 117 700 CO2e reduced per year (kg)
  • Live car free – 1000 up to 5300
  • Avoid one long range flight per year – 700 up to 2800
  • Purchase green energy – less than 100, up to 2500
  • Reduce effects of driving – 1190
  • Eat a plant based diet – 300 up to 1600

Moderate Impact Actions

  • Home heating/cooling efficiency – 180
  • Install solar panels/renewables
  • Use public transportation, ride a bike, or walk
  • Buy energy efficient products
  • Conserve energy – 210
  • Reduce food waste – 370
  • Eat less meat – 230
  • Reduce consumption in general (of products)
  • Reuse – 5
  • Recycle – 210
  • Eat local – 0 up to 360

Low Impact Actions

  • Conserve water
  • Eliminate unnecessary travel
  • Minimize waste
  • Plant a tree – 6 up to 60
  • Compost
  • Purchase carbon offsets
  • Reduce lawn mowing
  • Eco tourism
  • Keep backyard chickens
  • Buy Eco labelled products
  • Calculate your home’s carbon footprint

Civic Actions

  • Spread awareness
  • Influence employer’s actions
  • Influence school’s actions

–, and


Some specific solutions to mitigating GG emissions and climate change might include:

  • More efficient use of residential electronics, and new technology for household electronics
  • More efficient use of residential appliances
  • Retrofit residential HVAC
  • Tillage and residue management
  • Insulation retrofits for residential buildings
  • Hybrid cars
  • Waste recycling
  • Lighting – switch from incandescent to LED lights (residential)
  • Retrofit insulation (commercial)
  • Better motor systems efficiency for vehicles
  • Cropland nutrient management, particulary with fertilizer
  • Clinker substitution by fly ash
  • Electricity from landfill gas/methane
  • Efficiency improvements by different industries
  • Rice management
  • 1st generation biofuels
  • Small hydro
  • Reduced slash and burn agriculture conversion
  • Reduced pastureland conversion
  • Grassland management
  • Geothermal energy
  • Organic soil restoration
  • Building energy efficiency in new builds
  • 2nd gen biofuels
  • Degraded land restoration
  • Pastureland afforestation
  • Nuclear energy
  • Degraded forest reforestation
  • Low penetration wind technology and energy
  • Solar CSP technology and energy
  • Solar PV technology and energy
  • High penetration wind technology and energy
  • Reduced intensive agriculture conversion
  • Power plant biomass co-firing
  • Coal CCS new build
  • Iron and steel CCS new build
  • Coal CCS retrofit
  • Gas plant CCS retrofit



Ideas for mitigation in each sector where greenhouse gases come from might include:

  • eliminate the burning of coal, oil and, eventually, natural gas
  • invest in companies practicing carbon capture and storage
  • use plant-derived plastics, biodiesel, wind power, solar and renewable energy
  • Invest in building upgrades and new buildings – thicker and better insulation
  • Build Better roads
  • More efficient cement production processes – more efficient fuels to fire up the kilns
  • Less vehicle travel – more transit, bike and walking.
  • Better and less use of planes and jets
  • Buy less in general – energy is used to make all products, so it makes sense to cut back
  • Use more efficient lighting and appliances
  • Go vegetarian
  • Stop deforestation, and plant more trees
  • Work on overpopulation
  • Renewable energy experimentation
  • Biofuels, and hydrolisation
  • Geoengineering



  • Carbon taxes and carbon tariffs
  • Choose a utility company that generates at least half its power from wind or solar and has been certified
  • Insulate your home, and have more efficient heating and cooling
  • Offer tax credits for homes and businesses that install carbon efficient tech
  • Energy efficient appliances – refrigerators, washing machines, and other appliances, look for the Energy Star label
  • Saving water reduces carbon pollution, too. That’s because it takes a lot of energy to pump, heat, and treat your water. So take shorter showers, turn off the tap while brushing your teeth, and switch to WaterSense-labeled fixtures and appliances.
  • Eat the food you buy. Make less of it meat. Meat is resource intensive
  • Change to LEDs – LED lightbulbs use up to 80 percent less energy than conventional incandescents.
  • Pull all plugs and ‘idle’ devices
  • Gas-smart cars, such as hybrids and fully electric vehicles, save fuel and money. And once all cars and light trucks meet 2025’s clean car standards, which means averaging 54.5 miles per gallon, they’ll be a mainstay. For good reason: Relative to a national fleet of vehicles that averaged only 28.3 miles per gallon in 2011, Americans will spend $80 billion less at the pump each year and cut their automotive emissions by half.
  • Maintain cars -If all Americans kept their tires properly inflated, we could save 1.2 billion gallons of gas each year. A simple tune-up can boost miles per gallon anywhere from 4 percent to 40 percent, and a new air filter can get you a 10 percent boost.
  • Planes, trains and automobiles – choosing to live in walkable smart-growth cities and towns with quality public transportation leads to less driving, less money spent on fuel, and less pollution in the air. Less frequent flying can make a big difference, too. “Air transport is a major source of climate pollution,” Haq says. “If you can take a train instead, do that.”
  • Pay for carbon offsets



According to

  • To keep global temperature rise below the agreed 2°C, global carbon emission must peak in the next decade and from 2070 onward must be negative
  • The goal, with the Paris Agreement in mind, is limiting warming to 2℃ above pre-industrial levels. The Paris Agreement went further, aiming to “pursue efforts” towards a more ambitious goal of just 1.5℃. Given we’re already at around 1℃ of warming, that’s a relatively short-term goal.
  • The warming will slow to a potentially manageable pace only when human emissions are reduced to zero. The good news is that they are now falling in many countries as a result of programs like fuel-economy standards for cars, stricter building codes and emissions limits for power plants. But experts say the energy transition needs to speed up drastically to head off the worst effects of climate change
  • The energy sources with the lowest emissions include wind turbines, solar panels, hydroelectric dams and nuclear power stations. Power plants burning natural gas also produce fewer emissions than those burning coal. Using renewables can be costlier in the short term
  • Burning gas instead of coal in power plants reduces emissions in the short run, though gas is still a fossil fuel and will have to be phased out in the long run
  • “Clean coal” is an approach in which the emissions from coal-burning power plants would be captured and pumped underground. It has yet to be proven to work economically, but some experts think it could eventually play a major role.



  • Mitigation of climate change are actions to reduce greenhouse gas emissions, or enhance the capacity of carbon sinks to absorb greenhouse gases from the atmosphere.
  • There is a large potential for future reductions in emissions by a combination of activities, including energy conservation and increased energy efficiency; the use of low-carbon energy technologies, such as renewable energy, nuclear energy, and carbon capture and storage; and enhancing carbon sinks through, for example, reforestation and preventing deforestation.
  • A 2015 report by Citibank concluded that transitioning to a low carbon economy would yield positive return on investments.
  • Apart from mitigation, adaptation and climate engineering are other options for responses.



Climate change mitigation:

  • Mitigation involves reducing emissions, becoming more efficient with energy usage,  or increasing carbon sinks (reforestation)



Climate change adaptation:

  • Climate change adaptation is a response to global warming, that seeks to reduce the vulnerability of social and biological systems to relatively sudden change and thus offset the effects of global warming.
  • Even if emissions are stabilized relatively soon, global warming and its effects should last many years, and adaptation would be necessary to the resulting changes in climate.
  • Adaptation is especially important in developing countries since those countries are predicted to bear the brunt of the effects of global warming.
  • That is, the capacity and potential for humans to adapt (called adaptive capacity) is unevenly distributed across different regions and populations, and developing countries generally have less capacity to adapt.
  • Furthermore, the degree of adaptation correlates to the situational focus on environmental issues. Therefore, adaptation requires the situational assessment of sensitivity and vulnerability to environmental impacts



Climate engineering:

  • Climate engineering or climate intervention, commonly referred to as geoengineering, is the deliberate and large-scale intervention in the Earth’s climate system, usually with the aim of mitigating the adverse effects of global warming.
  • Climate engineering is an umbrella term for measures that mainly fall into two categories: greenhouse gas removal and solar radiation management.
  • Greenhouse gas removal approaches, of which carbon dioxide removal represents the most prominent subcategory addresses the cause of global warming by removing greenhouse gases from the atmosphere.
  • Solar radiation management attempts to offset effects of greenhouse gases by causing the Earth to absorb less solar radiation.
  • Some carbon dioxide removal practices, such as afforestation, ecosystem restoration and bio-energy with carbon capture and storage projects, are underway to a limited extent.
  • Most experts and major reports advise against relying on climate engineering techniques as a main solution to global warming, in part due to the large uncertainties over effectiveness and side effects. However, most experts also argue that the risks of such interventions must be seen in the context of risks of dangerous global warming.



According to Wikipedia:

  • Excess CO2 emitted since the pre-industrial era is projected to remain in the atmosphere for centuries to millennia, even after emissions stop. Even if human carbon dioxide emissions were to completely cease, atmospheric temperatures are not expected to decrease significantly for thousands of years.



1. IPCC Fifth Assessment Report –















16. Hannah Ritchie and Max Roser (2018) – “CO₂ and other Greenhouse Gas Emissions”. Published online at Retrieved from: ‘’ [Online Resource] 



Climate Change & Greenhouse Gas Emissions: Causes, Sources, Effects, Solutions & Forecasts

Climate Change: Causes, Sources, Effects, & Solutions

Climate change is one of the most talked about, if not the most talked about global issue.

When we talk about Climate Change, we also usually talk about global warming and greenhouse gases.

In this guide we outline what climate change is, the causes and sources, the effects, and what potential solutions might be on how to prevent it.

We also talk about how global warming and greenhouse gases tie into climate change as a whole.


Summary – What To Know About Climate Change

Climate change in a nutshell is the warming of the earth’s surface (via the sun’s solar radiation, and eventually infrared radiation) – with the warming process being amplified by greenhouse gases such as carbon dioxide (the main gas), but also methane, nitrous oxide and other gases.

From the evidence gathered, climate modelling done, and scientific formulas used – there is a consensus that humans are most likely the primary cause for the warming we are seeing today. Activities such as electricity production (that burns fossil fuels like coal), and vehicles (that burn petroleum) emit huge amounts of GHGs through burning of fossil fuels.

This warming period is usually expressed as the warming that has taken place since around 1950/60.

Temperatures have risen (up to 2019) around 0.8 to 0.9 degrees celcius compared to pre industrial levels, when carbon dioxide levels started increasing rapidly.

This rapid increase in carbon dioxide level (parts per million in the air) coincides with humans’ increased combustion of fossil fuels since the start of the industrial revolution.

What scientists do admit is that there are things they do know about climate change, things they think they might know, and things they are uncertain about that they can only make educated forecasts about with the information available.

They also admit that climate change feedback processes can be complex – leading to warming in some areas, and cooling in others (each area in the world has it’s own local or micro climate).

There’s also variables in the form of what we as humans will do in the future. What we do to mitigate emissions, adapt to changes, and reduce emissions will all impact how climate predictions can be made into the future.

As mentioned above, when it comes to climate change, a good way to look at it might be – what we are fairly certain we know, what we think we might know, and what we might be uncertain about.


What Is Climate Change?

  • Climate change is a change in the pattern of weather, and related changes in oceans, land surfaces and ice sheets, occurring over time scales of decades or longer



What Is Global Warming?

Global warming (i.e. an increase in the earth’s surface temperature) is just one factor in the overall climate change issue.

So, climate change is the all encompassing issue, whereas global warming is a ‘sub factor’ or ‘side effect’ in the overall issue.


What Is The Main Climate Change Problem?

It’s a very wide ranging problem with many factors and sub issues, causes, effects etc. to consider.

These factors and specific issues also differ country by country (and even state by state).

But, the core of the problem is the rise in the earth’s average surface temperature since the industrial revolution and particularly since the late 19th century, which has been largely driven by increased carbon dioxide and other human caused emissions in the atmosphere (carbon dioxide levels have sharply increased to unseen levels from 1950 to the current day).

A big cause for this is the burning of fossil fuels for electricity and heat production, transportation, industry (factories and production of goods and raw materials), and agriculture and clearing of land.


The planet’s average surface temperature has risen about 1.62 degrees Fahrenheit (0.9 degrees Celsius) since the late 19th century.

Most of the warming occurred in the past 35 years, with the five warmest years on record taking place since 2010. Not only was 2016 the warmest year on record, but eight of the 12 months that make up the year — from January through September, with the exception of June — were the warmest on record for those respective months.

Temperature is the one that gets all the attention, but there’s also other issues like:

  • Warming oceans
  • Shrinking ice sheets
  • Glacial retreat
  • Decreased snow cover
  • Sea level rise
  • Declining Arctic sea ice
  • Extreme/severe natural events
  • Ocean acidification
  • + more



What Are Greenhouse Gases?

Greenhouse gases are gases emitted from human and natural sources on earth, that rise up and sit in the earth’s atmosphere like a blanket.

This blanket of greenhouse gases lets through solar radiation from the sun (light). It also absorbs and re-emits infrared radiation (heat) from and back to the earth’s surface.

They get the name greenhouse gas because they have a similar effect that greenhouse glass has whereby the glass traps some IR radiation heat inside the greenhouse.

Greenhouse gases can be divided into two main types:

  • Greenhouse gases being emitted directly by human activities – Carbon dioxide (CO2) is the main one. Then methane (CH4), and nitrous oxide (N2O). Then others include ozone (O3), and synthetic gases (the ‘F’ gases), such as chlorofluorocarbons (CFCs) and hydrofluorocarbons (HFCs)
  • Other greenhouse gases – Water vapour is also a major greenhouse gas, but its concentration in the atmosphere is not influenced directly by human activities (it is influenced indirectly though by the production of carbon dioxide).
  • The most important greenhouse gases are water vapour and carbon dioxide (CO2). Both are present at very small concentrations in the atmosphere.
  • The two most abundant gases in the atmosphere are nitrogen (comprising 78 per cent of the dry atmosphere) and oxygen (21 per cent), but they have almost no greenhouse effects.
  • Water vapour varies considerably in space and time because it has a short ‘lifetime’ in the atmosphere. Because of this variation, it is difficult to measure globally averaged water vapour concentration.
  • Carbon dioxide has a much longer lifetime and is well mixed throughout the atmosphere. The current concentration is about 0.04 per cent.



  • Today, human activities are directly increasing atmospheric concentrations of CO2, methane and nitrous oxide, plus some chemically manufactured greenhouse gases such as halocarbons.
  • These human generated gases enhance the natural greenhouse effect and further warm the surface.
  • In addition to the direct effect, the warming that results from increased concentrations of long-lived greenhouse gases can be amplified by other processes.
  • A key example is water vapour amplification. Human activities are also increasing aerosols in the atmosphere, which reflect some incoming sunlight. This human-induced change offsets some of the warming from greenhouse gases.



What Is The Greenhouse Gas Effect?

There are two main types of greenhouse gas effects:

  • The natural green house gas effect which happens via the natural carbon cycle
  • The enhanced greenhouse gas effect which happens via human activities that add carbon dioxide on top of the natural emission of carbon dioxide

The thing is – we need the natural carbon cycle and natural greenhouse gas effect to make earth habitable. Without it, the earth would be -18ºC (minus 18 degrees) – and the earth would be uninhabitable.

The problem is the enhanced/human induced greenhouse releases carbon into the atmosphere faster than it can be removed by other parts of the carbon cycle.

This is called the ‘greenhouse effect’, and the gases that cause it by interacting with infrared radiation are called greenhouse gases. The most important are water vapour (which humans can’t directly control), carbon dioxide (CO2) and methane.

Since the Industrial Revolution, energy-driven consumption of fossil fuels has led to a rapid increase in CO2 emissions, disrupting the global carbon cycle and leading to a planetary warming impact.



How Does The Greenhouse Effect Actually Work?

What happens in the greenhouse effect it:

  • Solar radiation (light) comes from the sun and is emitted onto the earth’s surface (the sun’s energy intensity and the distance of the sun from earth affect how much solar radiation we get)
  • This solar radiation hits the earth’s surface, is converted to IR radiataion (heat) and warms the earth
  • Some IR radiation is emitted back to space, and some of it does escape into space
  • Some IR radiation gets absorbed by greenhouse gases in the atmosphere and re-emitted back onto the earth’s surface and troposphere – causing more heating than normal
  • Greenhouse gases, particularly carbon, gather in the atmosphere at a higher rate due to human activity like burning fossil fuels than they would during the natural carbon cycle

You can see how this works visually here:

the greenhouse effect

Credit: Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal

Page Link:


  • The Sun serves as the primary energy source for Earth’s climate.
  • Some of the incoming sunlight is reflected directly back into space, especially by bright surfaces such as ice and clouds, and the rest is absorbed by the surface and the atmosphere.
  • Much of this absorbed solar energy is re-emitted as heat (longwave or infrared radiation).
  • The atmosphere in turn absorbs and re-radiates heat, some of which escapes to space. Any disturbance to this balance of incoming and outgoing energy will affect the climate. For example, small changes in the output of energy from the Sun will affect this balance directly.
  • If all heat energy emitted from the surface passed through the atmosphere directly into space, Earth’s average surface temperature would be tens of degrees colder than today. Greenhouse gases in the atmosphere, including water vapour, carbon dioxide, methane, and nitrous oxide, act to make the surface much warmer than this, because they absorb and emit heat energy in all directions (including downwards), keeping Earth’s surface and lower atmosphere warm.
  • Without this greenhouse effect, life as we know it could not have evolved on our planet.
  • Adding more greenhouse gases to the atmosphere makes it even more effective at preventing heat from escaping into space.
  • When the energy leaving is less than the energy entering, Earth warms until a new balance is established.



What Is The Natural Carbon Cycle, And The Natural Greenhouse Gas Effect?

The natural cycle of carbon emission and absorption into and out of the atmosphere by living things and the natural environment.

All living organisms contain carbon, as do gases (such as carbon dioxide) and minerals (such as diamond, peat and coal). The movement of carbon between large natural reservoirs in rocks, the ocean, the atmosphere, plants, soil and fossil fuels is known as the carbon cycle.

The carbon cycle includes the movement of carbon dioxide:

  • into and out of our atmosphere
  • between the atmosphere, plants and other living organisms through photosynthesis, respiration and decay
  • between the atmosphere and the top of the oceans.

On longer time scales, chemical weathering and limestone and fossil fuel formation decrease atmospheric carbon dioxide levels, whereas volcanoes return carbon to the atmosphere. This is the dominant mechanism of control of carbon dioxide on timescales of millions of years.

Because the carbon cycle is essentially a closed system, any decrease in one reservoir of carbon leads to an increase in others.

For at least the last several hundred thousand years, up until the Industrial Revolution, natural sources of carbon dioxide were in approximate balance with natural ‘sinks’, producing relatively stable levels of atmospheric carbon dioxide.

‘Sinks’ are oceans, plants and soils, which absorb more carbon dioxide than they emit (in contrast, carbon sources emit more than they absorb).



What Is The Human/Enhanced Greenhouse Gas Effect?

Greenhouse gases (mainly carbon dioxide) emitted into the atmosphere mainly by human activity.

Refer to the ’causes’ section below for the sources of these carbon dioxide emissions.

The total carbon cycle is the natural carbon cycle and human carbon cycle together. That can be seen here:

total carbon cycle

Credit: Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal



Why Is Carbon Dioxide Considered The Main Greenhouse Gas?

There’s two reasons for this:

  • CO2 is responsible for more of an increase in the amount of energy (and therefore heat) reaching Earth’s surface than the other greenhouse gases. Other gases have more potent heat-trapping ability molecule per molecule than CO2 (e.g. methane), but are simply far less abundant in the atmosphere.
  • CO2 remains in the atmosphere longer than the other major heat-trapping gases


Explained in deeper detail…

  • Greenhouse gases are climate drivers
  • By measuring the abundance of heat-trapping gases in ice cores, the atmosphere, and other climate drivers along with models, the IPCC calculated the “radiative forcing” (RF) of each climate driver—in other words, the net increase (or decrease) in the amount of energy reaching Earth’s surface attributable to that climate driver.
  • Positive RF values represent average surface warming and negative values represent average surface cooling. In total, CO2 has the highest positive RF (see Figure 1) of all the human-influenced climate drivers compared by the IPCC.
  • Other gases have more potent heat-trapping ability molecule per molecule than CO2 (e.g. methane), but are simply far less abundant in the atmosphere.
  • CO2 remains in the atmosphere longer than the other major heat-trapping gases emitted as a result of human activities. It takes about a decade for methane (CH4) emissions to leave the atmosphere (it converts into CO2) and about a century for nitrous oxide (N2O).
  • After a pulse of CO2 is emitted into the atmosphere, 40% will remain in the atmosphere for 100 years and 20% will reside for 1000 years, while the final 10% will take 10,000 years to turn over. This literally means that the heat-trapping emissions we release today from our cars and power plants are setting the climate our children and grandchildren will inherit.
  • Water vapor is the most abundant heat-trapping gas, but rarely discussed when considering human-induced climate change. The principal reason is that water vapor has a short cycle in the atmosphere (10 days on average) before it is incorporated into weather events and falls to Earth, so it cannot build up in the atmosphere in the same way as carbon dioxide does.
  • However, a vicious cycle exists with water vapor, in which as more CO2 is emitted into the atmosphere and the Earth’s temperature rises, more water evaporates into the Earth’s atmosphere, which increases the temperature of the planet. The higher temperature atmosphere can then hold more water vapor than before.



Explained in another way…

  • Carbon dioxide is not the only greenhouse gas of concern for global warming and climatic change. There are a range of greenhouse gases, which include methane, nitrous oxide, and a range of smaller concentration trace gases such as the so-called group of ‘F-gases’.
  • Greenhouse gases vary in their relative contributions to global warming; i.e. one tonne of methane does not have the same impact on warming as one tonne of carbon dioxide. These differences can be defined using a metric called ‘Global Warming Potential’ (GWP). GWP can be defined on a range of time-periods, however the most commonly used (and that adopted by the IPCC) is the 100-year timescale (GWP100).
  • You can look at the GWP100 value of key greenhouse gases relative to carbon dioxide. The GWP100metric measures the relative warming impact one molecule or unit mass of a greenhouse gas relative to carbon dioxide over a 100-year timescale. For example, one tonne of methane would have 28 times the warming impact of tonne of carbon dioxide over a 100-year period. GWP100 values are used to combine greenhouse gases into a single metric of emissions called carbon dioxide equivalents (CO2e). CO2e is derived by multiplying the mass of emissions of a specific greenhouse gas by its equivalent GWP100 factor. The sum of all gases in their CO2e form provide a measure of total greenhouse gas emissions.
  • We see the contribution of different gases to total greenhouse gas emissions. These are measured based on their carbon-dioxide equivalent values. Overall we see that carbon dioxide accounts for around three-quarters of total greenhouse gas emissions. However, both methane and nitrous oxide are also important sources, accounting for around 17 and 7 percent of emissions, respectively.
  • Collectively, HFC, PFC and SF6 are known as the ‘F-gases’. Despite having a very strong warming impact per unit mass (i.e. a high global warming potential), these gases are emitted in very small quantities; they therefore make only a small contribution to total warming.



  • Carbon dioxide is the largest single contributor to human-induced climate change. NASA describes it as ‘the principal control knob that governs the temperature of Earth’. Although other factors (such as other long-lived greenhouse gases, water vapour and clouds) contribute to Earth’s greenhouse effect, carbon dioxide is the dominant greenhouse gas that humans can control in the atmosphere.



  • Scientists have determined that, when all human and natural factors are considered, Earth’s climate balance has been altered towards warming, with the biggest contributor being increases in CO2.



Do Humans Only Affect Climate Change Through Greenhouse Gases?


  • Greenhouse gases emitted by human activities alter Earth’s energy balance and thus its climate.
  • But, humans also affect climate by changing the nature of the land surfaces (for example by clearing forests for farming) and through the emission of pollutants that affect the amount and type of particles in the atmosphere.



Causes Of Climate Change (Sources, Sectors & Countries)

The main driver/cause of climate change is carbon emissions from human activity.

These human activities mainly include the burning of fossil fuels – for vehicles, for electricity generation at power plants and so on.

Water vapour accounts for about half the present-day greenhouse effect, but its concentration in the atmosphere is not influenced directly by human activities. The amount of water in the atmosphere is related mainly to changes in the Earth’s temperature. For example, as the atmosphere warms it is able to hold more water. Although water vapour absorbs heat, it does not accumulate in the atmosphere in the same way as other greenhouse gases; it tends to act as part of a feedback loop rather than being a direct cause of climate change.

So, let’s get more specific about where carbon dioxide comes from according to different sources:

EPA tracks total U.S. emissions by publishing the Inventory of U.S. Greenhouse Gas Emissions and Sinks. This annual report estimates the total national greenhouse gas emissions and removals associated with human activities across the United States.

The primary sources of greenhouse gas emissions in the United States are –

  • Transportation – nearly 28.5 percent of 2016 greenhouse gas emissions
  • Electricity Production – 28.4 percent of 2016 greenhouse gas emissions
  • Industry – 22 percent of 2016 greenhouse gas emissions
  • Commercial and residential – 11 percent of 2016 greenhouse gas emissions
  • Agriculture – 9 percent of 2016 greenhouse gas emissions
  • Land Use And Forestry – offset of 11 percent of 2016 greenhouse gas emissions



Combustible fossil fuels such as coal, power plant gas, oil, vehicles and big industry are the largest source of carbon dioxide. The production is from various items such as iron, steel, cement, natural gas, solid waste combustion, lime, ammonia, limestone, cropland, soda ash, aluminum, petrochemical, titanium and phosphoric acid. Carbon dioxide accounts for nearly 85 percent of all emissions and is produced when natural gas, petroleum and coal are used. The major areas where these fuels are used include electricity generation, transportation, industry and in residential and commercial buildings.



87 percent of all human-produced carbon dioxide emissions come from the burning of fossil fuels like coal, natural gas and oil. The remainder results from the clearing of forests and other land use changes (9%), as well as some industrial processes such as cement manufacturing (4%).

– Further breakdown at


Since the Industrial Revolution there has been a large increase in human activities such as fossil fuel burning, land clearing and agriculture, which affect the release and uptake of carbon dioxide.

According to the most recent Emissions Overview, carbon dioxide and other greenhouse gases are produced in NSW (in Australia) by the following activities or sources:

  • stationary energy sources, such as coal-fired power stations (47 per cent)
  • transport (18 per cent)
  • coal mines (12 per cent)
  • agriculture (11 per cent)
  • land use (7 per cent)
  • land change (3 per cent)
  • waste (2 per cent).

Carbon dioxide released into the atmosphere from burning fossil fuels carries a different chemical fingerprint from that released by natural sources such as respiration and volcanoes. This makes it possible to identify the contribution of human activity to greenhouse gas production.

Data collected by CSIRO show that the concentration of carbon dioxide in our atmosphere in 2018 was approximately 404 parts per million. The level of carbon dioxide in the Earth’s atmosphere is now higher than at any time over the past 800,000—and possibly 20 million—years.

Global atmospheric concentrations of the other greenhouse gases (methane and nitrous oxide) also now exceed pre-industrial values.



Global greenhouse gas emissions can be broken down by sectoral sources in these sections:

  • Energy (energy, manufacturing and construction industries and fugitive emissions): emissions are inclusive of public heat and electricity production; other energy industries; fugitive emissions from solid fuels, oil and gas, manufacturing industries and construction.
  • Transport: domestic aviation, road transportation, rail transportation, domestic navigation, other transportation.
  • International bunkers: international aviation; international navigation/shipping.
  • Residential, commercial, institutional and AFF: Residential and other sectors.
  • Industry (industrial processes and product use): production of minerals, chemicals, metals, pulp/paper/food/drink, halocarbons, refrigeration and air conditioning; aerosols and solvents; semicondutor/electronics manufacture; electrical equipment.
  • Waste: solid waste disposal; wastewater handling; waste incineration; other waste handling.
  • Agriculture: methane and nitrous oxide emissions from enteric fermentation; manure management; rice cultivation; synthetic fertilizers; manure applied to soils; manure left on pasture; crop residues; burning crop residues, savanna and cultivation of organic soils.
  • Land use: emissions from the net conversion of forest; cropland; grassland and burning biomass for agriculture or other uses.
  • Other sources: fossil fuel fires; indirect nitrous oxide from non-agricultural NOx and ammonia; other anthropogenic sources.



Emissions by country…

Cumulative emissions –  As of 2014 – China’s rapid growth in emissions over the last few decades now makes it the world’s second largest cumulative emitter, although it still comes in at less than 50% of the US total.

Annual emissions – In 2014, we can see that a number of low to middle income nations are now within the top global emitters. In fact, China is now the largest emitter, followed by (in order) the US, EU-28, India, Russia, Indonesia, Brazil, Japan, Canada and Mexico. Note that a number of nations that are already top emitters are likely to continue to increase emissions as they undergo development.

In contrast to CO2 emissions growth in low to middle income economies, trends across many high income nations have stabilized, and in several cases decreased in recent decades. Despite this downward trend across some nations, emissions growth in transitioning economies dominates the global trend—as such, global annual emissions have continued to increase over this period.

Per Capita emissions – With a few exceptions, there is an important north-south divide in terms of per capita emissions. Most nations across sub-Saharan Africa, South America and South Asia have per capita emissions below five tonnes per year (many have less than 1-2 tonnes). This contrasts with the global north where emissions are typically above five tonnes per person (with North America above 15 tonnes). The monthly emissions per capita in rich countries are mostly higher than the yearly emissions per capita in poorer countries. The largest emitter, Qatar, has per capita emissions of 50 tonnes per year (1243 times that of Chad, the lowest emitter).

Note that carbon dioxide is not the only greenhouse gas which contributes to climate change—nitrous oxide and methane are also greenhouse gases, but are not included here. Food production, especially intensive livestock-rearing for meat and dairy, is a major contributor to both of these non-CO2 GHGs. Since capita meat intake is strongly linked to GDP levels, per capita emissions of nitrous oxide and methane tend to be much larger in high-income nations.

C02 emissions by source vary depending on the country – we are talking about gas, liquid (i.e. oil), solid (coal and biomass), flaring, and cement production. In the present day, solid and liquid fuel dominate, although contributions from gas production are also notable. Cement and flaring at the global level remain comparably small. has some great missions charts and graphs which show total GHG emissions, as well as Carbon Dioxide, Methane and Nitrous Oxide Emissions by sector, activity, country and more as %’s, parts per million etc. –

You can see the stats, as well as trends of emissions.

The EPA has also outlined each sector where greenhouse gases are emitted. You can read more about those sectors and sources for gases in our guide on solutions to climate change.


Effects Of Climate Change

What is important to note is that there are already some effects that have taken place (such as the rise in temperature, shrinking ice etc.

But, future effects can only be forecasted – but not guaranteed.


Climate change affects the world as a whole, but can also affect different countries, and regions within those countries differently.

There are environmental, social and economic effects.

Some of the current and future effects of climate change are…

  • Warming oceans
  • Shrinking ice sheets
  • Glacial retreat
  • Decreased snow cover
  • Sea level rise
  • Declining Arctic sea ice
  • Extreme events
  • Ocean acidification [due to increased carbon levels]



Global warming and a changing climate have a range of potential ecological, physical and health impacts, including extreme weather events (such as floods, droughts, storms, and heatwaves); sea-level rise; altered crop growth; and disrupted water systems.



  • The enhanced greenhouse effect is expected to change many of the basic weather patterns that make up our climate, including wind and rainfall patterns and the incidence and intensity of storms.
  • Every aspect of our lives is in some way influenced by the climate. For example, we depend on water supplies that exist only under certain climatic conditions, and our agriculture requires particular ranges of temperature and rainfall.



  • Ice is melting in both polar ice caps and mountain glaciers. Lakes around the world, including Lake Superior, are warming rapidly — in some cases faster than the surrounding environment. Animals are changing migration patterns and plants are changing the dates of activity, such as trees budding their leaves earlier in the spring and dropping them later in the fall.
  • There’s an increase in average temperatures and the temperature extremes, there’s extreme weather events, there’s ice melt, there’s sea level rise and acidification, plants and animals are affected, and there are social consequences relating to agriculture, food security and health implication just to name a few.



  • Global effects – hotter days, rising sea levels, more frequent and intense extreme weather events, oceans are warming and acidifying. As humans, every aspect of our life is reliant on the natural environment. This includes the food we eat, the air we breathe, the water we drink, the clothes we wear and the products that are made and sold to create jobs and drive the economy. We need a healthy and stable climate for these things.
  • Country Specific effects such as Australia – temperature rises, water shortages, increased fire threats, drought, weed and pest invasions, intense storm damage and salt invasion.
  • Threatening of the Great Barrier Reef.
  • Animals and plants – One in six species is at risk of extinction because of climate change and habitat destruction and environmental change.
  • Food and Farming – Changes to rainfall patterns, increasingly severe drought, more frequent heat waves, flooding and extreme weather make it more difficult for farmers to graze livestock and grow produce, reducing food availability and making it more expensive to buy.
  • Water – Reduced rainfall and increasingly severe droughts may lead to water shortages.
  • Coastal erosion – Rising sea levels and more frequent and intense storm surges will see more erosion of Australia’s coastline, wearing away and inundating community and residential properties.
  • Health – Increasingly severe and frequent heat waves may lead to death and illness, especially among the elderly. Higher temperatures and humidity could also produce more mosquito-borne disease.
  • Damage to homes – Increasingly severe extreme weather events like bushfires, storms, floods, cyclones and coastal erosion, will see increased damage to homes, as well as more costly insurance premiums.
  • Coral bleaching – Rising temperatures and acidity within our oceans is contributing to extreme coral bleaching events, like the 2016 event that destroyed more than one-third of the Great Barrier Reef.
  • Overall – Within Australia, the effects of global warming vary from region to region.
    The impacts of global warming are already being felt across all areas of Australian life, and these will continue to worsen if we do not act now to limit global warming to 1.5°C.



Future effects might be:

Global climate change has already had observable effects on the environment. Glaciers have shrunk, ice on rivers and lakes is breaking up earlier, plant and animal ranges have shifted and trees are flowering sooner.

Scientists have high confidence that global temperatures will continue to rise for decades to come, largely due to greenhouse gases produced by human activities. The Intergovernmental Panel on Climate Change (IPCC), which includes more than 1,300 scientists from the United States and other countries, forecasts a temperature rise of 2.5 to 10 degrees Fahrenheit over the next century.

According to the IPCC, the extent of climate change effects on individual regions will vary over time and with the ability of different societal and environmental systems to mitigate or adapt to change.

The IPCC predicts that increases in global mean temperature of less than 1.8 to 5.4 degrees Fahrenheit (1 to 3 degrees Celsius) above 1990 levels will produce beneficial impacts in some regions and harmful ones in others. Net annual costs will increase over time as global temperatures increase.

“Taken as a whole,” the IPCC states, “the range of published evidence indicates that the net damage costs of climate change are likely to be significant and to increase over time.”

According to the Third and Fourth National Climate Assessment Reports, future effects will be…

  • change through this century and beyond depending on how many greenhouse gases we emit and how sensitive our climate is to them
  • temperatures will continue to rise
  • Frost free season and growing season will lengthen
  • There will be changes in precipitation patterns
  • There will be more droughts and heat waves
  • Hurricanes will become stronger and more intense
  • Sea levels will rise between 1-4 feet by 2100
  • The Arctic is likely to become ice free

NASA also outline the US regional effects so far in Northeast, Northwest, Southeast, Midwest and Southwest. For example, in the Southwest – increased heat, drought and insect outbreaks, all linked to climate change, have increased wildfires. Declining water supplies, reduced agricultural yields, health impacts in cities due to heat, and flooding and erosion in coastal areas are additional concerns.



Evidence That Climate Change Is A Real Issue, & Is A Direct Cause Of Other Problems

In summary, the main points of evidence are:

  • it has been proved how much of a warming effect greenhouse gases like carbon dioxide have on the earth
  • there was a sharp rise in carbon dioxide levels (in parts per million) since the industrial revolution in the 19th century, and in particular since 1950 – most of it from human activity
  • there was rise in average global earth surface (air) temperature in the same time – compared to pre 1950’s levels
  • there has been a change in other events and things in the same time such as sea levels, ice melting, etc. – compared to pre 1950’s levels


So, you have to be able to prove:

  • Greenhouse gases warm the earth and it’s climate
  • Humans are emitting greenhouse gases at certain levels
  • The GHG’s that human are emitting are causing the warming (as opposed to natural emissions causing it)
  • There are negative side effects of this warming (e.g. sea level rise, ice melt etc.)
  • That this warming and these negative side effects wouldn’t be happening, or happening to the extent they are now without the human caused greenhouse gas emissions (essentially comparing what is happening now with excess emissions, to a baseline without these heavy emissions)
  • Some further information explaining this and evidence is…
  • The finding that the climate has warmed in recent decades and that human activities are producing global climate change has been endorsed by every national science academy that has issued a statement on climate change, including the science academies of all of the major industrialized countries.
  • Scientific consensus is normally achieved through communication at conferences, publication in the scientific literature, replication (reproducible results by others), and peer review. In the case of global warming, many governmental reports, the media in many countries, and environmental groups, have stated that there is virtually unanimous scientific agreement that human-caused global warming is real and poses a serious concern.
  • Several studies of the consensus have been undertaken. Among the most-cited is a 2013 study of nearly 12,000 abstracts of peer-reviewed papers on climate science published since 1990, of which just over 4,000 papers expressed an opinion on the cause of recent global warming. Of these, 97% agree, explicitly or implicitly, that global warming is happening and is human-caused. It is “extremely likely” that this warming arises from “… human activities, especially emissions of greenhouse gases …” in the atmosphere. Natural change alone would have had a slight cooling effect rather than a warming effect.



  • [the current warming trend] is extremely likely (greater than 95 percent probability) to be the result of human activity since the mid-20th century and proceeding at a rate that is unprecedented over decades to millennia.

– IPCC Fifth Assessment Report via


  • For 400,000 years, carbon dioxide levels have never been above 280 to 300 parts per million
  • During ice ages, COlevels were around 200 parts per million (ppm), and during the warmer interglacial periods, they hovered around 280 ppm
  • Around 1950, carbon dioxide levels surpassed 300 parts per million, and as of 2013, levels surpassed 400 parts per million
  • This rise in carbon closely mimics our burning of fossil fuels in the same time. What we know about fossil fuels is that they emit carbon dioxide, and 60 percent of fossil-fuel emissions stay in the air.
  • If fossil-fuel burning continues at a business-as-usual rate, such that humanity exhausts the reserves over the next few centuries, CO2 will continue to rise to levels of order of 1500 ppm. The atmosphere would then not return to pre-industrial levels even tens of thousands of years into the future.



  • The Earth’s climate has changed throughout history. Just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era — and of human civilization. Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives.
  • The current warming trend is of particular significance because most of it is extremely likely (greater than 95 percent probability) to be the result of human activity since the mid-20th century and proceeding at a rate that is unprecedented over decades to millennia.
  • Earth-orbiting satellites and other technological advances have enabled scientists to see the big picture, collecting many different types of information about our planet and its climate on a global scale. This body of data, collected over many years, reveals the signals of a changing climate.
  • The heat-trapping nature of carbon dioxide and other gases was demonstrated in the mid-19th century.Their ability to affect the transfer of infrared energy through the atmosphere is the scientific basis of many instruments flown by NASA. There is no question that increased levels of greenhouse gases must cause the Earth to warm in response.
  • Ice cores drawn from Greenland, Antarctica, and tropical mountain glaciers show that the Earth’s climate responds to changes in greenhouse gas levels. Ancient evidence can also be found in tree rings, ocean sediments, coral reefs, and layers of sedimentary rocks. This ancient, or paleoclimate, evidence reveals that current warming is occurring roughly ten times faster than the average rate of ice-age-recovery warming.
  • Further to this, there are these events tied to the above:
  • Global temperature rise – The planet’s average surface temperature has risen about 1.62 degrees Fahrenheit (0.9 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere. Most of the warming occurred in the past 35 years, with the five warmest years on record taking place since 2010. Not only was 2016 the warmest year on record, but eight of the 12 months that make up the year — from January through September, with the exception of June — were the warmest on record for those respective months.
  • Warming Oceans – The oceans have absorbed much of this increased heat, with the top 700 meters (about 2,300 feet) of ocean showing warming of 0.302 degrees Fahrenheit since 1969.
  • Shrinking Ice Sheets – The Greenland and Antarctic ice sheets have decreased in mass. Data from NASA’s Gravity Recovery and Climate Experiment show Greenland lost an average of 281 billion tons of ice per year between 1993 and 2016, while Antarctica lost about 119 billion tons during the same time period. The rate of Antarctica ice mass loss has tripled in the last decade.
  • Glacial Retreat – Glaciers are retreating almost everywhere around the world — including in the Alps, Himalayas, Andes, Rockies, Alaska and Africa.
  • Decreased Snow Cover – Satellite observations reveal that the amount of spring snow cover in the Northern Hemisphere has decreased over the past five decades and that the snow is melting earlier.
  • Sea Level Rise – Global sea level rose about 8 inches in the last century. The rate in the last two decades, however, is nearly double that of the last century.
  • Declining Arctic Sea Ice – Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades.
  • Extreme Events – The number of record high temperature events in the United States has been increasing, while the number of record low temperature events has been decreasing, since 1950. The U.S. has also witnessed increasing numbers of intense rainfall events.
  • Ocean Acidification – Since the beginning of the Industrial Revolution, the acidity of surface ocean waters has increased by about 30 percent. This increase is the result of humans emitting more carbon dioxide into the atmosphere and hence more being absorbed into the oceans. The amount of carbon dioxide absorbed by the upper layer of the oceans is increasing by about 2 billion tons per year.



  • Look at how the world has warmed since the Industrial Revolution.
  • We see that over the last few decades, temperatures have risen sharply at the global level — to approximately 0.8 degrees celsius higher than our 1961-1990 baseline.
  • When extended back to 1850, we see that temperatures then were a further 0.4 degrees colder than they were in our 1961-1990 baseline.
  • Overall, if we look at the total temperature increase since pre-industrial times, this therefore amounts to approximately 1.2 degrees celcius. We have now surpassed the one-degree mark, an important marker as it brings us more than halfway to the global limit of keeping warming below two degrees celsius.
  • It’s also important to look at trends by hemisphere (North and South), as well as the tropics (defined as 30 degrees above and below the equator).
  • Here we see that the median temperature increase in the North Hemisphere is higher, at closer to 1.4 degrees celcius since 1850, and less in the Southern Hemisphere (closer to 0.8 degrees celcius). Evidence suggests that this distribution is strongly related to ocean circulation patterns (notably the North Atlantic Oscillation) which has resulted in greater warming in the northern hemisphere.



  • Climate change is happening
  • Tens of thousands of scientists in more than a hundred nations have amassed an overwhelming amount of evidence that humans are the cause
  • We are statistically more confident that humans cause climate change than that smoking causes cancer
  • There are nine main independently studied, but physically related, lines of evidence
  • (it is really the first seven that, combined, point to human activities as the only explanation of rising global temperatures since the Industrial Revolution, and the subsequent climate changes (such as ice melt and sea level rise) that have occurred due to this global warming.)
  • Those nine lines of evidence are:
  1. Simple chemistry – when we burn carbon-based materials, carbon dioxide (CO2) is emitted (research beginning in 1900s)
  2. Basic accounting of what we burn, and therefore how much CO2 we emit (data collection beginning in 1970s)
  3. Measuring CO2 in the atmosphere and trapped in ice to find that it is increasing and that the levels are higher than anything we’ve seen in hundreds of thousands of years (measurements beginning in 1950s)
  4. Chemical analysis of the atmospheric CO2 that reveals the increase is coming from burning fossil fuels (research beginning in 1950s)
  5. Basic physics that shows us that CO2 absorbs heat (research beginning in 1820s)
  6. Monitoring climate conditions to find that recent warming of the Earth is correlated to and follows rising CO2 emissions (research beginning in 1930s)
  7. Ruling out natural factors that can influence climate like the sun and ocean cycles (research beginning in 1830s)
  8. Employing computer models to run experiments of natural versus human-influenced simulations of Earth (research beginning in 1960s)
  9. Consensus among scientists who consider all previous lines of evidence and make their own conclusions (polling beginning in 1990s)



  • CO2 keeps the Earth warmer than it would be without it. Humans are adding CO2 to the atmosphere, mainly by burning fossil fuels. And there is empirical evidence that the rising temperatures are being caused by the increased CO2.
  • The reason that the Earth is warm enough to sustain life is because of greenhouse gases in the atmosphere. These gases act like a blanket, keeping the Earth warm by preventing some of the sun’s energy being re-radiated into space. The effect is exactly the same as wrapping yourself in a blanket – it reduces heat loss from your body and keeps you warm. If we add more greenhouse gases to the atmosphere, the effect is like wrapping yourself in a thicker blanket: even less heat is lost.
  • So how can we tell what effect CO2 is having on temperatures, and if the increase in atmospheric CO2 is really making the planet warmer?
  • One way of measuring the effect of CO2 is by using satellites to compare how much energy is arriving from the sun, and how much is leaving the Earth. What scientists have seen over the last few decades is a gradual decrease in the amount of energy being re-radiated back into space. In the same period, the amount of energy arriving from the sun has not changed very much at all. This is the first piece of evidencemore energy is remaining in the atmosphere.
  • The primary greenhouse gases – carbon dioxide (CO2), methane (CH4), water vapour, nitrous oxide and ozone – comprise around 1% of the air. This tiny amount has a very powerful effect, keeping the planet 33°C (59.4°F) warmer than it would be without them. (The main components of the atmosphere – nitrogen and oxygen – are not greenhouse gases, because they are virtually unaffected by long-wave, or infrared, radiation). This is the second piece of evidencea provable mechanism by which energy can be trapped in the atmosphere
  • We now look at the amount of CO2 in the air. We know from bubbles of air trapped in ice cores that before the industrial revolution, the amount of CO2 in the air was approximately 280 parts per million (ppm). In June 2013, the NOAA Earth System Research Laboratory in Hawaii announced that, for the first time in thousands of years, the amount of CO2 in the air had gone up to 400ppm. That information gives us the next piece of evidenceCO2 has increased by nearly 43% in the last 150 years.
  • The final piece of evidence is ‘the smoking gun’, the proof that CO2 is causing the increases in temperature. CO2 traps energy at very specific wavelengths, while other greenhouse gases trap different wavelengths.  In physics, these wavelengths can be measured using a technique called spectroscopy. When looking at the different wavelengths of energy, measured at the Earth’s surface, on a Spectroscopy Graph – among the spikes you can see energy being radiated back to Earth by ozone (O3), methane (CH4), and nitrous oxide (N20). But the spike for CO2 dwarfs all the other greenhouse gases, and tells us something very important: most of the energy being trapped in the atmosphere corresponds exactly to the wavelength of energy captured by CO2.
  • To sum up:
  • 1. What is happening – More energy is remaining in the atmosphere on Earth
  • 2. How is this happening – Greenhouse gases are the mechanism by which energy is trapped in the atmosphere
  • 3. Why is this happening – CO2 has increased by nearly 50% in the last 150 years and the increase is from burning fossil fuels
  • 4. Linking the tw0 – energy being trapped in the atmosphere corresponds exactly to the wavelengths of energy captured by CO2
  • This is empirical evidence that proves, step by step, that man-made carbon dioxide is causing the Earth to warm up.



  • The science on the human contribution to modern warming is quite clear. Humans emissions and activities have caused around 100% of the warming observed since 1950
  • Since 1850, almost all the long-term warming can be explained by greenhouse gas emissions and other human activities.
  • If greenhouse gas emissions alone were warming the planet, we would expect to see about a third more warming than has actually occurred. They are offset by cooling from human-produced atmospheric aerosols.
  • Aerosols are projected to decline significantly by 2100, bringing total warming from all factors closer to warming from greenhouse gases alone.
  • Natural variability in the Earth’s climate is unlikely to play a major role in long-term warming.
  • Some of the findings that back up these results are…
  • Greenhouse gas forcings match actual observed global surface temperature warming – Scientists measure the various factors that affect the amount of energy that reaches and remains in the Earth’s climate. They are known as “radiative forcings”. They can be natural (such as volcanoes) and man made (such as greenhouse gases). When looking at a graph that shows the estimated role of each different climate forcing in changing global surface temperatures since records began in 1850, of all the radiative forcings analysed, only increases in greenhouse gas emissions produce the magnitude of warming experienced over the past 150 years.
  • Human forcings match actual observed global surface temperature warmings
  • Land temperatures are rising faster now – Land temperatures have warmed considerably faster than average global temperatures over the past century, with temperatures reaching around 1.7C above pre-industrial levels in recent years.
  • From the models, future forecasts are that land warms by around 4C by 2100 compared to 3C globally for surface temperature
  • While human factors explain all the long-term warming, there are some specific periods that appear to have warmed or cooled faster than can be explained based on our best estimates of radiative forcing.
  • Short term warming or cooling may occur via natural factors, but long term natural variability to impact long-term warming trends is extremely unlikely
  • Internal variability is likely to have a much larger role in regional temperatures. For example, in producing unusually warm periods in the Arctic and the US in the 1930s.
  • In summary – While there are natural factors that affect the Earth’s climate, the combined influence of volcanoes and changes in solar activity would have resulted in cooling rather than warming over the past 50 years. The global warming witnessed over the past 150 years matches nearly perfectly what is expected from greenhouse gas emissions and other human activity, both in the simple model examined here and in more complex climate models. The best estimate of the human contribution to modern warming is around 100% . Some uncertainty remains due to the role of natural variability, but researchers suggest that ocean fluctuations and similar factors are unlikely to be the cause of more than a small fraction of modern global warming.

– answers many climate change related questions that give evidence of the link between greenhouse gases and climate change at

These questions and answers include:

    • Is the climate warming (lists the range of observations, indications and evidence that show warming has occured)
    • How do scientists know that recent climate change is largely caused by human activities?
    • CO2 is already in the atmosphere naturally, so why are emissions from human activity significant?
    • What role has the Sun played in climate change in recent decades?
    • What do changes in the vertical structure of atmospheric temperature – from the surface up to the stratosphere – tell us about the causes of recent climate change?
    • Climate is always changing. Why is climate change of concern now?
    • Is the current level of atmospheric CO2concentration unprecedented in Earth’s history?
    • Is there a point at which adding more CO2 will not cause further warming?
    • Does the rate of warming vary from one decade to another?
    • Does the recent slowdown of warming mean that climate change is no longer happening?
    • If the world is warming, why are some winters and summers still very cold?
    • Why is Arctic sea ice reducing while Antarctic sea ice is not?
    • How does climate change affect the strength and frequency of floods, droughts, hurricanes and tornadoes?
    • How fast is sea level rising?
    • What is ocean acidification and why does it matter?
    • How confident are scientists that Earth will warm further over the coming century?
    • Are climate changes of a few degrees a cause for concern?
    • What are scientists doing to address key uncertainties in our understanding of the climate system?
      • Are disaster scenarios about tipping points like ‘turning off the Gulf Stream’ and release of methane from the Arctic a cause for concern?
    • If emissions of greenhouse gases were stopped, would the climate return to the conditions of 200 years ago?



Climate Change Evidence Stats

C02 & Other Greenhouse Gas Level Changes

The global mean CO2 level in 2013 was 395 parts per million. This concentration represents a 43 per cent increase from pre-industrial levels; it is likely to be at the highest concentration in at least 2 million years.

Methane and nitrous oxide concentrations, mostly from agriculture, have increased by 150% and 20% respectively since 1750.



Records of air bubbles in ancient Antarctic ice show us that carbon dioxide and other greenhouse gases are now at their highest concentrations for more than 800,000 years.



Global Surface Temperature Change

We have tracked significant increase in global temperatures of at least 0.85°C and a sea level rise of 20cm over the past century.



You can check out global temperature change at 


Global Sea Level Change

We have tracked significant increase in global temperatures of at least 0.85°C and a sea level rise of 20cm over the past century.



You can check out global sea level at 


Average Sea Surface Temperature Change

You can check out average sea surface temperature which is rising at


Looking At Evidence Overall

Overall, you can’t just look at temperature (air temperature, land temperature, water temperature) to diagnose or assess climate change. You also have to look at sea levels, ocean acidity, ice sheets, ecosystem trends, and other factors to get a well rounded answer.


Ways To Monitor The Impact Climate Change Is Having Now & Into The Future

Some of the long-term effects of global climate change in the United States are listed in the Third and Fourth National Climate Assessment Reports.

But, NASA list some of the effects and expected effects of climate change at

(Some effects that scientists had predicted in the past would result from global climate change are now occurring: loss of sea ice, accelerated sea level rise and longer, more intense heat waves.)

Among the impacts to look out for and monitor and link to each other are:

  • Continued C02 parts per million levels rising
  • Continued earth air surface temperature rising
  • Land temperature rising
  • Ocean temperatures rising
  • Glaciers shrinking
  • Ice on rivers and lakes breaking up earlier
  • Plant and animal ranges shifting
  • Trees and plants flowering sooner
  • Loss of sea ice
  • Accelerated sea level rise
  • Longer, more intense heat waves
  • Frost free and growing seasons lengthening (The largest increases in the frost-free season (more than eight weeks) are projected for the western U.S., particularly in high elevation and coastal areas.)
  • Changes in precipitation patterns – trend towards increased heavy precipitation events
  • More droughts, heat waves and hot days (By the end of this century, what have been once-in-20-year extreme heat days (one-day events) are projected to occur every two or three years over most of the nation.)
  • Cold waves to become less intense
  • Hurricanes becoming stronger and more intense (The intensity, frequency and duration of North Atlantic hurricanes, as well as the frequency of the strongest (Category 4 and 5) hurricanes, have all increased since the early 1980s. The relative contributions of human and natural causes to these increases are still uncertain)
  • Sea levels to rise (Global sea level has risen by about 8 inches since reliable record keeping began in 1880. It is projected to rise another 1 to 4 feet by 2100. This is the result of added water from melting land ice and the expansion of seawater as it warms.)
  • Land subsidence to increase (land sinking)
  • Flooding of coastal and sea side land to increase
  • Arctic Ocean to become ice free
  • Infrastructure, agriculture, fisheries and ecosystems will be increasingly compromised
  • Increasing wildfire, insect outbreaks and tree diseases
  • Increasing ocean acidity
  • Decreased freshwater availability
  • Increased erosion



Debate & Disagreement Over Climate Change & Global Warming

You can read more about the debate and controversy over climate change and it’s impact/effects at 


Answers To Skeptical Arguments Against Climate Change

Skeptical Science has a good resource answering common skeptical arguments against climate change:



How Are C02 Concentrations Obtained In Current Time, & From The Past?

More recently, there are observatories that measure air CO2 levels.

But, historic CO2 levels can be found in ice cores, and also rock sediment samples from the ocean and lakes.

There are other ancient samples (such as tree rings, studying ancient organisms etc.) that can also be used to get an idea of CO2 levels from the past.

Read more about how climate change indicators and past CO2 levels are measured in this guide.


Climate Change & Trade/Import Between Developed vs Developing Countries

  • Climate change can lead to lead to widespread drought, disease and desperation in some of the world’s poorest regions
  • Migration by refugees affected by climate change is predicted in the future
  • Richer nations have a lot of carbon emissions contained in the products and materials they import from developing countries
  • Of the carbon emissions that European consumers are personally responsible for, around 22% are allocated elsewhere under conventional carbon accounting practices. For consumers in the US, the figure is around 15%.
  • Heavy industry and the constant demand for consumer goods are key contributors to climate change
  • 30% of global greenhouse gas emissions are produced through the process of converting metal ores and fossil fuels into the cars, washing machines and electronic devices that help prop up richer economies
  • Richer nations have more purchasing power and through their consumption of products, contribute to emissions and pollution
  • For every item bought or sold there is a rise in GDP, and with each 1% increase in GDP there is a corresponding 0.5 to 0.7% rise in carbon emissions
  • For metal ores alone, the extraction rate more than doubled between 1980 and 2008
  • Every time you buy a new car, for instance, you effectively mine 3-7g of “platinum group metals” to coat the catalytic converter. The six elements in the platinum group have the greatest environmental impact of all metals, and producing just one kilo requires the emission of thousands of kilos of CO₂
  • This is only one example of the toll poorer countries are taking to satisfy richer countries
  • The problem is that in poorer countries choose to accept this behavior for a variety of factors, and citizens see it as the only way to get out of poverty (because it provides jobs)
  • Richer nations must start implementing sustainable material strategies that address a product’s entire lifecycle from mining to manufacturing, use, and eventually to disposal. They must consider the well being of the people and environment in the countries they are importing from
  • Consumers can also vote with their dollars and buy from more ethical and sustainable countries



Potential Climate Change Solutions (Mitigation, Adaptation, Carbon Sequestering)

The best solution is to bring emissions to zero as soon as possible.

But, realistically – there is going to need to be a different approach to doing that in each industry and sector of society.

Two big examples are – renewable energy sources in the electricity generation sector, and cleaner cars in the transport sector.

There needs to be an approach that considers employment, the economy and practicality right now, and the future environmental needs of the future.

Building infrastructure, getting funding, transferring to new technologies and power sources – all take time and have technical challenges – so it’s something that requires serious planning and research as to how to best do it.


Some specific solutions might include:

  • More efficient use of residential electronics, and new technology for household electronics
  • More efficient use of residential appliances
  • Retrofit residential HVAC
  • Tillage and residue management
  • Insulation retrofits for residential
  • Hybrid cars
  • Waste recycling
  • Lighting – switch from incandescent to LED lights (residential)
  • Retrofit insulation (commercial)
  • Better motor systems efficiency
  • Cropland nutrient management
  • Clinker substitution by fly ash
  • Electricity from landfill gas
  • Efficiency improvements by different industries
  • Rice management
  • 1st generation biofuels
  • Small hydro
  • Reduced slash and burn agriculture conversion
  • Reduced pastureland conversion
  • Grassland management
  • Geothermal energy
  • Organic soil restoration
  • Building energy efficiency in new builds
  • 2nd gen biofuels
  • Degraded land restoration
  • Pastureland afforestation
  • Nuclear energy
  • Degraded forest reforestation
  • Low penetration wind technology and energy
  • Solar CSP technology and energy
  • Solar PV technology and energy
  • High penetration wind technology and energy
  • Reduced intensive agriculture conversion
  • Power plant biomass co-firing
  • Coal CCS new build
  • Iron and steel CCS new build
  • Coal CCS retrofit
  • Gas plant CCS retrofit



Also according to

  • To keep global temperature rise below the agreed 2°C, global carbon emission must peak in the next decade and from 2070 onward must be negative
  • The goal, with the Paris Agreement in mind, is limiting warming to 2℃ above pre-industrial levels. The Paris Agreement went further, aiming to “pursue efforts” towards a more ambitious goal of just 1.5℃. Given we’re already at around 1℃ of warming, that’s a relatively short-term goal.
  • The warming will slow to a potentially manageable pace only when human emissions are reduced to zero. The good news is that they are now falling in many countries as a result of programs like fuel-economy standards for cars, stricter building codes and emissions limits for power plants. But experts say the energy transition needs to speed up drastically to head off the worst effects of climate change
  • The energy sources with the lowest emissions include wind turbines, solar panels, hydroelectric dams and nuclear power stations. Power plants burning natural gas also produce fewer emissions than those burning coal. Using renewables can be costlier in the short term
  • Burning gas instead of coal in power plants reduces emissions in the short run, though gas is still a fossil fuel and will have to be phased out in the long run
  • “Clean coal” is an approach in which the emissions from coal-burning power plants would be captured and pumped underground. It has yet to be proven to work economically, but some experts think it could eventually play a major role.



Mitigation of climate change are actions to reduce greenhouse gas emissions, or enhance the capacity of carbon sinks to absorb greenhouse gases from the atmosphere.

There is a large potential for future reductions in emissions by a combination of activities, including energy conservation and increased energy efficiency; the use of low-carbon energy technologies, such as renewable energy, nuclear energy, and carbon capture and storage; and enhancing carbon sinks through, for example, reforestation and preventing deforestation.

A 2015 report by Citibank concluded that transitioning to a low carbon economy would yield positive return on investments.

Apart from mitigation, adaptation and climate engineering are other options for responses.



Cost Of Pursuing Climate Change Mitigation

According to OurWorldInData, these are very loose and very roughly estimated costs to pursue climate change mitigation. These costs have lots of variables:

The possible cost-benefit of taking global and regional action on climate change is often a major influencing factor on the effectiveness of mitigation agreements and measures.

If we aggressively pursue all of the low-cost abatement opportunities currently available, the total global economic cost would be €200-350 billion per year by 2030. This is less than one percent of the forecasted global GDP in 2030.

If we include these additional opportunities, our maximum technical abatement potential by 2030 totals 47 billion tonnes of CO2e per year. Our maximum global potential is therefore a 65-70% reduction relative to our current projected pathway.



Recent Greenhouse Gas Trends (Total Greenhouse Gas Emissions)

Since 1990, gross U.S. greenhouse gas emissions have increased by about 2 percent. From year to year, emissions can rise and fall due to changes in the economy, the price of fuel, and other factors.

In 2016, U.S. greenhouse gas emissions decreased compared to 2015 levels. This decrease was largely driven by a decrease in emissions from fossil fuel combustion, which was a result of multiple factors including substitution from coal to natural gas consumption in the electric power sector; warmer winter conditions that reduced demand for heating fuel in the residential and commercial sectors.

You can see total US GHG emissions between 1990 and 2016 at



EPA also shows the total global and national GG emissions by %:

  • National –
  • Global –

In the US you can see carbon dioxide emissions have been gradually decreasing since around 2007 to 2016.


Forecast For Climate Change Into The Future

Climate change and it’s effects can be forecasted into the future, but not with an absolute guarantee (some forecasts from the past weren’t completely accurate).

There variables that can impact how quickly warming takes place, and how the earth and different indicators in different parts of the world react.

Climate models can forecast for 100’s of different scenarios based on these variables.

There may be warming in some parts of the world, and there may be cooling in others just as one example.

It’s more realistic to be aware of the indicators and causes, understand what potential future scenarios might be, and continue to monitor them and adjust expectations accordingly.

What most experts do agree on though is that it’s in our best interests to decrease human GHG emissions as soon as possible.



  • The continued burning of fossil fuels will inevitably lead to further climate warming. The complexity of the climate system is such that the extent of this warming is difficult to predict, particularly as the largest unknown is how much greenhouse gas we keep emitting.
  • The IPCC has developed a range of emissions scenarios or Representative Concentration Pathways (RCPs) to examine the possible range of future climate change.
  • Using scenarios ranging from business-as-usual to strong longer-term managed decline in emissions, the climate model projections suggest the global mean surface temperature could rise by between 2.8°C and 5.4°C by the end of the 21st century. Even if all the current country pledges submitted to the Paris conference are achieved we would still only just be at the bottom end of this range.
  • The sea level is projected to rise by between 52cm and 98cm by 2100, threatening coastal cities, low-lying deltas and small island nations. Snow cover and sea ice are projected to continue to reduce, and some models suggest that the Arctic could be ice-free in late summer by the latter part of the 21st century.
  • Heat waves, droughts, extreme rain and flash flood risks are projected to increase, threatening ecosystems and human settlements, health and security. One major worry is that increased heat and humidity could make physical work outside impossible.
  • Changes in precipitation are also expected to vary from place to place. In the high-latitude regions (central and northern regions of Europe, Asia and North America) the year-round average precipitation is projected to increase, while in most sub-tropical land regions it is projected to decrease by as much as 20%, increasing the risk of drought.
  • In many other parts of the world, species and ecosystems may experience climatic conditions at the limits of their optimal or tolerable ranges or beyond.
  • Human land use conversion for food, fuel, fibre and fodder, combined with targeted hunting and harvesting, has resulted in species extinctions some 100 to 1000 times higher than background rates. Climate change will only speed things up.
  • This is the challenge our world leaders face. To keep global temperature rise below the agreed 2°C, global carbon emission must peak in the next decade and from 2070 onward must be negative: we must start sucking out carbon dioxide from the atmosphere.
  • Despite 30 years of climate change negotiations there has been no deviation in greenhouse gas emissions from the business-as-usual pathway, so many feel keeping global warming to less than 2°C will prove impossible.
  • Previous failures, most notably at Copenhagen in 2009, set back meaningful global cuts in emissions by at least a decade. Paris, however, offers a glimmer of hope.



  • Near- and long-term trends in the global energy system are inconsistent with limiting global warming at below 1.5 or 2 °C, relative to pre-industrial levels. Pledges made as part of the Cancún agreements are broadly consistent with having a likely chance (66 to 100% probability) of limiting global warming (in the 21st century) at below 3 °C, relative to pre-industrial levels.



What does the future of our carbon dioxide and greenhouse gas emissions look like? [here are] … a range of potential future scenarios of global greenhouse gas emissions (measured in gigatonnes of carbon dioxide equivalents), based on data from Climate Action Tracker. Here, five scenarios are shown:

  • No climate policies: projected future emissions if no climate policies were implemented; this would result in an estimated 4.1-4.8°C warming by 2100 (relative to pre-industrial temperatures)
  • Current climate policies: projected warming of 3.1-3.7°C by 2100 based on current implemented climate policies
  • National pledges: if all countries achieve their current targets/pledges set within the Paris climate agreement, it’s estimated average warming by 2100 will be 2.6-3.2°C. This will go well beyond the overall target of the Paris Agreement to keep warming “well below 2°C”.
  • 2°C consistent: there are a range of emissions pathways that would be compatible with limiting average warming to 2°C by 2100. This would require a significant increase in ambition of the current pledges within the Paris Agreement.
  • 1.5°C consistent: there are a range of emissions pathways that would be compatible with limiting average warming to 1.5°C by 2100. However, all would require a very urgent and rapid reduction in global greenhouse gas emissions.



Climate Change Overall Is A Complex Process – It Has Drivers, Amplifiers, Diminishers & Feedbacks That All Interact With Each Other

Based just on the physics of the amount of energy that CO2 absorbs and emits, a doubling of atmospheric CO2 concentration from pre-industrial levels (up to about 560 ppm) would, by itself, cause a global average temperature increase of about 1 °C (1.8 °F).

In the overall climate system, however, things are more complex; warming leads to further effects (feedbacks) that either amplify or diminish the initial warming.

The most important feedbacks involve various forms of water.

A warmer atmosphere generally contains more water vapour.

Water vapour is a potent greenhouse gas, thus causing more warming; its short lifetime in the atmosphere keeps its increase largely in step with warming. Thus, water vapour is treated as an amplifier, and not a driver, of climate change.

Higher temperatures in the polar regions melt sea ice and reduce seasonal snow cover, exposing a darker ocean and land surface that can absorb more heat, causing further warming.

Another important but uncertain feedback concerns changes in clouds. Warming and increases in water vapour together may cause cloud cover to increase or decrease which can either amplify or dampen temperature change depending on the changes in the horizontal extent, altitude, and properties of clouds.

The latest assessment of the science indicates that the overall net global effect of cloud changes is likely to be to amplify warming.

The ocean moderates climate change. The ocean is a huge heat reservoir, but it is difficult to heat its full depth because warm water tends to stay near the surface. The rate at which heat is transferred to the deep ocean is therefore slow; it varies from year to year and from decade to decade, and helps to determine the pace of warming at the surface.

Observations of the sub-surface ocean are limited prior to about 1970, but since then, warming of the upper 700 m (2,300 feet) is readily apparent. There is also evidence of deeper warming.

Surface temperatures and rainfall in most regions vary greatly from the global average because of geographical location, in particular latitude and continental position.

Both the average values of temperature, rainfall, and their extremes (which generally have the largest impacts on natural systems and human infrastructure), are also strongly affected by local patterns of winds.

Estimating the effects of feedback processes, the pace of the warming, and regional climate change requires the use of mathematical models of the atmosphere, ocean, land, and ice (the cryosphere) built upon established laws of physics and the latest understanding of the physical, chemical and biological processes affecting climate, and run on powerful computers.

Models vary in their projections of how much additional warming to expect (depending on the type of model and on assumptions used in simulating certain climate processes, particularly cloud formation and ocean mixing), but all such models agree that the overall net effect of feedbacks is to amplify warming.



Other Notes & Stats On Climate Change, C02 & Greenhouse Emissions

C02 and Economic development

Historically, CO2 emissions have been primarily driven by increasing fuel consumption. This energy driver has been, and continues to be, a fundamental pillar of economic growth and poverty alleviation. As a result, there is a strong correlation between per capita CO2 emissions and GDP per capita for countries.

There are also noticeable within-country inequalities in greenhouse gas emissions



C02 and Poverty alleviation

The link between economic growth and CO2 described above raises an important question: do we actually want the emissions of low-income countries to grow despite trying to reduce global emissions? In our historical and current energy system (which has been primarily built on fossil fuels), CO2 emissions have been an almost unavoidable consequence of the energy access necessary for development and poverty alleviation.

In general, we see a very similar correlation in both CO2 and energy: higher emissions and energy access are correlated to lower levels of extreme poverty. Energy access is therefore an essential component in improved living standards and poverty alleviation.

In an ideal world, this energy could be provided through 100% renewable energy: in such a world, CO2emissions could be an avoidable consequence of development. However, currently we would expect that some of this energy access will have to come from fossil fuel consumption (although potentially with a higher mix of renewables than older industrial economies). Therefore, although the global challenge is to reduce emissions, some growth in per capita emissions from the world’s poorest countries remains a sign of progress in terms of changing living conditions and poverty alleviation.



C02 Intensity Of Economies 

If economic growth is historically linked to growing CO2 emissions, why do countries have differing levels of per capita CO2 emissions despite having similar GDP per capita levels? These differences are captured by the differences in the CO2 intensity of economies; CO2 intensity measures the amount of CO2 emitted per unit of GDP (kgCO2 per int-$). There are two key variables which can affect the CO2 intensity of an economy:

  • Energy efficiency: the amount of energy needed for one unit of GDP output. This is often related to productivity and technology efficiency, but can also be related to the type of economic activity underpinning output. If a country’s economy transitions from manufacturing to service-based output, less energy is needed in production, therefore less energy is used per unit of GDP.
  • Carbon efficiency: the amount of CO2 emitted per unit energy (grams of CO2 emitted per kilowatt-hour). This is largely related to a country’s energy mix. An economy powered by coal-fired energy will produce higher CO2 emissions per unit of energy versus an energy system with a high percentage of renewable energy. As economies increase their share of renewable capacity, efficiency improves and the amount of CO2 emitted per unit energy falls.

Global CO2 intensity has been steadily falling since 1990.17 This is likely thanks to both improved energy and technology efficiency, and increases in the capacity of renewables. The carbon intensity of nearly all national economies has also fallen in recent decades. Today, we see the highest intensities in Asia, Eastern Europe, and South Africa. This is likely to be a compounded effect of coal-dominated energy systems and heavily industrialized economies.



C02 Intensity and Prosperity 

On average, we see low carbon intensities at low incomes; carbon intensity rises as countries transition from low-to-middle incomes, especially in rapidly growing industrial economies; and as countries move towards higher incomes, carbon intensity falls again.



C02 intensity of goods imported and exported by country

Some countries take on emissions via trade.

The net emissions transfers here is the COembedded in imported goods minus the COembedded in exported goods. This tells us whether a country is a net exporter or importer of emissions.

Based on the updated data gathered by Peters et al. (2012) and the Global Carbon Project, if we switched to a consumption-based reporting system (which corrects for this trade), in 2014 the annual CO2 emissions of many European economies would increase by more than 30% (the UK by 38%; Sweden by 66%; and Belgium’s emissions would nearly double); and the USA’s emissions would increase by 7%.

On the other hand, China’s emissions would decrease by 13%; India’s by 9%; Russia’s by 14% and South Africa by 29%. The goods exported from Russia, China, India, and the Middle East typically have a high carbon intensity, reflecting the fact that their exports are often manufactured goods.

In contrast, we see that exports from the UK, France, Germany and Italy are low; this is likely to be the higher share of export of service-based exports relative to those produced from heavy industry.

Production vs consumption based emissions – If a country’s consumption-based emissions are higher than its production-based emissions then it is a net importer of CO2. If production-based emissions are higher, it is a net exporter.






3. Hannah Ritchie and Max Roser (2018) – “CO₂ and other Greenhouse Gas Emissions”. Published online at Retrieved from: ‘’ [Online Resource]































Potential Solutions To Freshwater Depletion & Scarcity

Solutions To Freshwater Depletion, Scarcity, Stress & Shortages

The world’s freshwater supplies are limited, and in a lot of cases depleting.

Depletion of these sources of freshwater include one off natural events, and more permanent problems like overpopulation and climate change (plus other factors).

Dry countries with hotter climates, and lower income countries with water access issues in particular face big freshwater issues that cause a severe impact on people, the economy, animals and the natural environment.

We’ve collated some of the best and most innovative ideas being used, or that might be worth developing further to solve issues like freshwater depletion, scarcity, stress and shortages.

Let’s take a look


Summary – Solutions To Freshwater Depletion

Some of the biggest positive changes might be see by addressing:

  • The Agricultural, Industrial & Household sectors – the three main areas we use freshwater in society
  • Population growth – more people means more demand for water directly, and also for all the indirect uses of water such as growing food, manufacturing products, producing energy, and running households
  • Capture waste/sewage/industrial/energy production/agricultural and household water, treat it, and re-use/recycle it where possible – waste water and grey water re-use and recycling, once treated, is one of the biggest potential ways to make better use of the water we use
  • Find more ways to capture/harvest rainwater – increased harvesting rainwater on farms, industrially, and at the household level, can give us more access to freshwater
  • Improve irrigation efficiency in agriculture – like for example drip irrigation and installing timers and sensors on irrigation systems. Making irrigation more efficient, and addressing water waste via irrigation, can save a lot of water
  • Improve industrial/commercial and energy production water efficiency – these two sectors use farm more water than the household sector. Becoming more efficient in these sectors can provide significant returns 
  • Reduce water waste, especially from water pipes and water infrastructure – at the household level, more water is wasted BEFORE it gets to our houses. Upgrading and improving water pipes and water infrastructure is one way to address this, as well as installing more water pipe damage software and sensors – just as some examples
  • Explore how to be more energy efficient with water desalination (and less costly) – desalination is currently very energy intensive and expensive. Reducing energy consumptions requirements (and cost) for desalination, or developing technology that allows desalination to occur with sustainable energy and green energy would go a long way to addressing this
  • Address water pollution – water pollution and contamination reduces the overall amount of freshwater available to our growing populations
  • Consider the impact of climate change on natural water replenishment – climate and temperature impacts the natural water replenishment cycle via evaporation, precipitation and so on


Specific Ways To Address Freshwater Depletion


Per (note: we’ve paraphrased the descriptions):

… Population growth, urban development, farm production and climate change are increasing competition for fresh water and producing shortages.

Here’s a look at the first 19 areas where experts feel needed solutions will come.

[these are areas where solutions for coping with water scarcity in business and industry may come based on a] … poll of more than 1200 leading international experts in 80 countries)


1. Educate people on the various water issues, and help people change consumption habits

Educate people on how important water is, how much of it we have, how much to use, where we use it and the consequences if we don’t address the issue and become sustainable with our use of it.

Specifically we want to educate people, and motivate them to change their behavior when it comes to consuming water

At all levels, and across the sections of society where we use the most water, we have to change consumption habits

We’ve got to use less water, and/or use water more efficiently


2. Invest in new water conservation technologies

Groundwater is drying up, and rainfalls are becoming inconsistent

Manufacturing equipment, waste water capture and re-use equipment, household equipment – all use water

Invest in technology that saves, re captures, cleans and re-uses water

Make sure new technologies are energy efficient, as energy use with water conservation or purification tech can be an issue


3. Recycle waste water

From industries, agriculture and households

Find a way to treat waste water and re-use/recycle it. Some places like Singapore are trying to find ways to treat and recycle wastewater for drinking for example


4. Improve agricultural and irrigation practices

These activities use a lot of water – up to 70% of total usage in some countries

Getting more efficient, using less water, and growing/producing different foods and crops can help

We can either create new practices and technology, or improve existing ones (such as existing irrigation technology – like they’ve done in California)


5. Increase the price of water 

If we stop making non drinking fresh water so cheap – maybe we can make people and businesses use less of it

It may also decrease water waste and pollution


6. Develop energy efficient water desalination

Desalination uses ALOT of energy – this is one of the major drawbacks to it

Considering 97% of the world’s water is saline water – if we get this technology right – it opens things up a lot

Renewable energy desalination plants are a good option – such as solar powered plants

Having said this – a country needs money in the first place to experiment with this type of technology, so it’s not an option for low income countries


7. Improve water catchment and harvesting

Water catchment and water harvesting can help us catch more freshwater that falls on the land and on structures

The more water we catch and harvest, the more we have available to use. You see this in dams that get extended

This is important for places struck by climate change, places with irregular rainfall, and places with low freshwater supplies


8. Look to community based governments and partnerships

Local governments and communities have power to empower people at a grassroots level

It can filter up to the national level when change occurs here


9. Develop, enact and maintain better laws and regulations

There’s the Clean Water Act in the US for example – which the US government is thinking of expanding

Whatever the case, national and state governments worldwide have an important part to play with both legislature, and their policies and decisions on how to manage freshwater sources

Many people believe it’s the government’s responsibility to provide us with freshwater


10. Holistically manage ecosystems

We are talking about economic, cultural, and ecological systems

This is making systems work together instead of just on their own

Good examples of holistic management are communities that operate sewage treatment plants while pursuing partnerships with clean energy producers to use wastewater to fertilize algae and other biofuel crops.

The crops, in turn, soak up nutrients and purify wastewater, significantly reducing pumping and treatment costs.


11. Improve distribution infrastructure

Poor water infrastructure can cause health, pollution/contamination and economic problems

We are talking about pipe bursts, lack of treatment facilities, sewage and wastewater overflows and malfunction


12. Shrink corporate water footprints

We are talking about producing products and goods, and sustainable manufacturing

Business activity and industrial activity (factories, manufacturing facilities etc.) uses up a large amount of water

Bottled water is one industry that is highly questioned – if we improve drinking water infrastructure – why do we need bottled water in the first place? Why don’t people refill their existing water bottles?


13. Build international frameworks and institutional cooperation

Work together to have better binding watter agreements and behaviors between countries

Hold each other to higher standards

Regional agreements regarding transboundary or shared water bodies, and treaties need more attention


14. Address water pollution (and contamination)

We are specifically talking about creating and maintaining better water quality

Poor water quality leads to human health and biodiversity issues

Contamination includes things like bacteria – E coli is an example

Pollution includes things like oil pollution, agricultural pollution and wastewater and sewage pollution


15. Public common resources/equitable access

Access to drinking water has to be a right for everyone in every country

Governments need to find a way to do this at least, even if water use for other purposes isn’t as efficient as it can be

The water crisis in lower income countries shows us what happens when drinking water is hard to come by or access


16. R&D/Innovation

Public private partnerships between business and governments

One example— cities that operate sewage treatment plants are likely to pursue partnerships with clean energy producers to fertilize algae and other biofuel crops with wastewater.


17. Water projects in developing countries/transfer of technology

Climate change and water scarcity are producing the most dramatic consequences in developing regions

One proposed solution is to transfer water conservation technologies from developed countries to these dry areas.

Doing so is tricky because economies are weak and there are gaps in skills that often compel government and business authorities to impose these changes on local citizens.


18. Climate change mitigation

Climate change (greenhouse gases in particular) and water scarcity go hand-in-hand

As renewable energy options are pursued, the water consumption of these mitigation tactics must be considered in producing alternatives ranging from bio-energy crops to hydropower and solar power plants.


19. Population growth control

Because of the accelerating growth in global population, parts of the world could see a supply-demand gap of up to 65 percent in water resources by 2030.

Currently, more than one billion people don’t have access to clean water.

And with 70 percent of the world’s freshwater used for agriculture, water’s critical role in food production must be considered as climate and resource conditions change.



1. Solar Powered Water Purifiers

Make more contaminated water drinkable

Use zinc oxide and titanium dioxide in containers that expose it to ultraviolet radiation and cleanse the water – making it suitable to drink


2. Water leak software and monitors

Almost a third of water is wasted even before it reaches a home – at failed and leaking pipelines. And, then obviously at the household level there can be over usage and wastage.

Water leak monitors and software with a central operating hub/control centre can help against this.


3. Replacing water cleaning, with CO2 cleaning

We use a lot of water in cleaning in manufacturing

To give you an idea of how much, manufacturing a car requires nearly 40,000 gallons of water

CO2 cleaning involves the use of carbon dioxide in solid form, highly propelled dry ice particles out of a nozzle to clean a variety of different surfaces.

The technology can be used for composite aircraft and automotive structures, cleaning complex medical equipment, and dry cleaning operations in an eco-friendly way.

The CO2 required for these machines is recycled from other industrial uses, so not only does it contribute to solving the water shortage crisis, but also helps with climate change.


4. Lifesaver bottles

For emergencies and short term water issues.

It’s a special bottle that can instantly make water potable. It uses a pump to push the water through a 15-nanometer filter which cleans it of any bacteria or viruses.

Has a low financial and environmental cost


5. Improving shower water saving technology

Technology that helps shower water heat up quicker, and technology that collects wasted cold water and refilters it in at the right temperature


6. Showering without water

A lotion has been made that has a blend of chemicals that get rid of odors, bioflavonoids and essential oils. The lotion can be applied right onto the skin and is as effective as taking a regular shower.

Dry Bathing can help save 4 liters of water per person which can add up to many millions every single year and help billions of people who don’t have access to water stay clean and avoid the life-threatening bacteria that’s often found in the stagnant water some of these people use to bathe.




The 2030 Water Resources Group has brought together case studies from around the world of currently available, replicable and practical solutions for water use transformation.

Some of these solutions include:

  • Waterless dying technology in textile processing
  • Installation of soil moisture monitoring system to improve productivity
  • Resource efficient cleaner production in sugar factories
  • Balancing supply and demand through water metering
  • Public private partnerships for water system upgrades
  • Partnerships for cleaner textile production
  • Institutional reform in irrigation management
  • Reducing the cost of water re-use in the textile sector
  • Integrated irrigation modernisation projects
  • Basin based approach for groundwater management
  • Innovative financing arrangements
  • Active supply chain management in the textile industry
  • Effluent treatment and aquifer storage for agricultural use
  • Innovative PPP to improve water quality and availability
  • Corporate water efficiency targets in the mining industry
  • Reducing water use in fish and seafood processing
  • Zero liquid discharge and water reuse at a coal power plant
  • PPP to address regional water issues
  • Adapting to water scarcity at farm level
  • Community implemented aquifer recharge scheme
  • Institutional capacity building approach to managing industrial water use
  • Integrated water resource management in agriculutre
  • Water management in copper and gold mines
  • Reuse of municipal effluent at a petrochemical complex
  • New water from fog catchingReducing water and energy consumption in a chemical plant
  • Satellite based spatial data to aid in irrigation
  • Micro irrigation for food security
  • Creation of ‘new water’ from saline aquifer
  • High frequency intermittent drip irrigation
  • Water free milk powder factory
  • Maximising water reuse at a brewery
  • Social norms based customer engagement on water efficiency
  • Installation of drip irrigation systems
  • Emergency response to drought crisis
  • Air flow dyeing machines in textile production
  • Water use reduction strategy in food sector
  • Water reuse in the textile sector
  • Water reuse in the power and steel production sector
  • Water recycling in the food sector
  • Water recycling in paper production
  • Water reclamation for reuse and groundwater recharge
  • Water optimisation in the mining sector
  • Use of seawater in dual municipal water supply
  • Regional water conservation program
  • Wastewater reclamation and reuse network
  • Water loss management programs
  • Water efficiency audits of steam systems
  • Reducing water losses in a large distribution network
  • Water demand management strategy
  • Water demand management scheme
  • Reducing business risk through municipal leakage reduction
  • Water authority conservation program
  • Pressure management in municipalities
  • Wastewater reclamation to meet potable water demand
  • Pilot low cost irrigation scheduling
  • Managing evapotranspiration using quotas
  • Mine water recycling
  • Leakage reduction in primary schools
  • Leakage reduction in cities
  • Metering of non revenue water
  • Irrigation scheduling in grape farming
  • Managing water towards zero discharge
  • Irrigation optimisation
  • Irrigation network renewal
  • Irrigation management
  • Integrated watershed management
  • Improving water availability through wastewater treatment
  • Improved water management for sugar cane production
  • Improved water distribution management
  • Groundwater recharge
  • Groundwater conservation
  • Emergency water demand management
  • Domestic and business retrofit project
  • Direct dry cooling in the power sector
  • Behavioral change initiative
  • Aquifer recharge with stormwater
  • Advanced pressure management



  • Farmers are partnering with scientists and conservationists to recharge groundwater by inundating farm fields with wintertime floodwater, which then seeps through the soil to the aquifer below
  • … Another neglected water source can be found right below our feet. The world’s soils can hold eight times more water than all rivers combined, yet agricultural practices deplete soils, causing that critical water reservoir to shrink.  But this can be fixed by rebuilding soil health.  
  • By eliminating tillage and planting cover crops, farmers can build the soil’s carbon content and enable it to store more water. Even a one percentage-point increase in soil organic carbon can increase water-holding capacity by some 18,000 gallons per acre. Yet farmers plant cover crops on less than 3% of US farmland and practice conservation agriculture on only about seven percent of cropland worldwide.


Further Ideas & Solutions

1. Consider changing our production and purchasing habits

Specifically with food and clothing.

Meat production, and cotton plants for example use a lot of water.

Switching to vegetarian diets, and switching to bamboo, hemp, lyocell and similar less water intensive fabrics – can all help.


2. Decrease water contamination, and invest more cheap/efficient water contamination technology

Water contamination, particularly with E coli and bacteria, is a big problem

If we can decrease contamination (protect water sources better) and get better at treating water contamination in it – more water will be available in contaminated water sources


3. Decrease water pollution

Mostly pollution from agriculture (fertiliser, herbicide and pesticide) and waste water and sewage treatment pollutes water

Decrease this pollution, and get better at cleaning up pollution