Pros & Cons Of Wind Energy, Turbines & Farms Now & In The Future

Pros & Cons Of Wind Energy, Turbines & Farms Now & In The Future

As part of assessing the best energy sources for the future, we are looking at the pros and cons of these different energy sources.

This is our guide on the Pros & Cons Of Wind Energy, Turbines & Farms.

 

Summary – Pros & Cons Of Wind Energy, Wind Turbines & Wind Farms

Pros

  • Is renewable and sustainable (unlike fossil fuels)
  • Is clean energy that doesn’t emit greenhouse gases during operation
  • There is no re-fuelling that needs to take place once wind farms are set up (unlike coal plants for example)
  • Wind farms are generally simpler and less costly to maintain once in operation compared to coal plants and nuclear plants
  • Wind energy is getting cheaper for consumers in some countries (as the technology and cost to produce wind farms gets cheaper)
  • Doesn’t take up as much space and land as solar panels
  • Allows energy independence for individuals
  • Allows people to disconnect from the energy grid
  • Power output is OK
  • Good to use on homes
  • Good to use rurally
  • Wind farms can be set up with as many or as few wind turbines as desired, and the projects can be run in stages, unlike coal plants or nuclear plants that have to be built all at once
  • Wind energy is showing rapid growth in some parts of the world (like the MidWest in the US)

Cons

  • Power density and power per unit is not as good as coal or nuclear in a lot of instances
  • More of a supplementary power source for many cities as this stage – not yet suitable for largest scale power production
  • Not yet as cost efficient as solar (there’s more investment in development of solar at the moment)
  • Can be intermittent and an unpredictable energy sources (as it requires consistent wind to produce energy)
  • Not good in places with little wind
  • Not as portable as solar energy
  • Can have heavy upfront cost for larger scale wind farms
  • Time to break even from upfront costs can be 10, 20 or more years
  • Can be noisy if you live near a wind farm
  • Wind farms can sometimes be a hazard for flying wildlife
  • Aesthetics – wind farms tend not to look great
  • Demand for wind energy can be sensitive to fossil fuel prices
  • Demand for wind energy may decrease when tax credits stop in some countries or regions

Wind energy probably sits just behind solar as one of our best options as a long-term energy sources that is clean and renewable. It’s a smaller scale or supplementary energy source at this stage in most cases. With more development in technology, the potential can keep growing. One drawback is that it relies on wind – and not every location is as windy as others.

*Note – the above pros and cons are broad generalisations. Obviously there are different variables to each specific energy project that impact the final pros and cons (like new technology that reduces emissions for coal power plants just as one of many examples). Each energy project and situation (in different countries and cities) should be analysed individually. Having said that, some broad principles and patterns about the pros and cons of different energy sources tend to stay consistent too.

 

What Is Wind Energy/Power?

Wind power is the generation of electricity by using air flow to spin wind turbines, then converting the mechanical energy into electrical.

– renewableresourcescoalition.org

 

Pros Of Wind Energy, Turbines & Farms

  • Is Renewable & Sustainable – wind is actually a form of solar energy. Winds are created by a combination of uneven surfaces of the Earth, the Earth’s rotation on its axis, and imbalanced heating of the sun across our atmosphere. This means that for at least the next 5 billion years, we won’t run out of it.
  • Is Clean Energy – does not produce Greenhouse Gases while in use unlike coal, gas, and oil. Manufacture and installation of wind turbines does, but this is minimal compared to other energy sources. These set up GHGs are expected to be recouped within 9 months of clean operation in most cases
  • Fuel Is Free – once a wind turbine is set up, there is no fueling or refueling process that needs to take place unlike a coal power plant for example.
  • Running Costs Of Wind Turbines Are Relatively Low– after manufacture and install, a wind turbine requires little to maintain unlike a coal or nuclear plant.
  • Wind Energy Is Getting Cheaper For Consumers – cost to produce is gradually decreasing as demand increases and technology gets better. Since 1980, wind energy prices have decreased more than 80%. This is due to the vast amounts of research paying dividends as new and improved technology, in addition to demand for wind power consistently increasing. Future trends are expected to be the same.
  • Doesn’t Take Up Heaps Of Space Or Land – whilst wind turbines and farms do take up land, they don’t take up as much land or real estate as solar panels. The space in between wind turbines can be used for other things.
  • Energy Independent – wind energy can be produced most places in the world. It doesn’t have to be connected to a power grid. You also don’t have to rely on utility companies for electricity.
  • Decent Power Output – one large wind turbine, on average, has the capacity to generate enough electricity to power 600 U.S. homes.
  • Good Potential For Homes – In addition to be an independent energy source, wind energy gives individuals access to net metering which basically provides credit to electricity bills for any excess power generated in a given month. You actually get paid for extra energy production
  • Can Be Used Rurally – like solar energy, because wind energy is an independent energy source and doesn’t rely on a power grid, it has good rural use application.
  • Wind Energy Is Showing Rapid Growth In Some Regions – the Midwest that are moving away from heavy reliance on coal and have seen rapid growth in wind energy (insideclimatenews.org)

– renewableresourcescoalition.org, insideclimatenews.org

 

Cons Of Wind Energy, Turbines & Farms

  • Loses To Solar In Some Aspects – loses to solar for cost and aesthetic purposes. Also, companies like Tesla are pouring a lot of time and money into developing solar technology, and countries like Germany (a solar leader) are too.
  • Can Be Intermittent, & Unpredictable – Wind energy can be unpredictable, as wind and wind speeds often rise and fall in general and in different locations. This is unlike solar where at least you know where the sun rises and falls. Although wind can produce energy at night (unlike solar), it isn’t enough to offset it’s unpredictability.
  • Heavy Upfront Costs – Larger-scale wind farms and residential turbines are very costly, and fossil fuels, such as coal and natural gas, currently produce electricity at a rather low rate, which makes it hard for wind to compete in the short term.
  • Take Time To Break Even In Terms Of Cost – it takes anywhere from 10 to 20 years before a wind turbine breaks even.
  • Noise Pollution – turbines and farms create noise pollution that other energy sources, such as solar, don’t. But some technology is making noise less of an issue as time goes on.
  • Difficult To Live Near Large Scale Wind Farms – because of the noise pollution.
  • Biological/Environmental Impact – once installed, wind turbines present a safety hazard to flying creatures such as birds that might fly into them. There isn’t this problem with solar.
  • Aesthetics – especially in residential cases, there seems to be more people who prefer the look of solar panels in and around their homes than windmills and wind turbines.
  • Demand for wind energy can be sensitive to fossil fuel prices – wind energy outlook is highly sensitive to natural gas prices, with wind becoming less competitive when gas prices are low [in the US] (insideclimatenews.org)
  • Demand for wind energy might decrease when there are is no tax credit support – some experts support this view, whilst others don’t (insideclimatenews.org)

– renewableresourcescoalition.org, insideclimatenews.org

 

Sources

1. https://www.renewableresourcescoalition.org/wind-energy-pros-cons/

2. https://insideclimatenews.org/news/28012019/eia-annual-energy-outlook-coal-renewable-wind-utility-analyst-projections-impact

Solar Energy Pros & Cons Now & Into The Future

Solar Energy Pros & Cons Now & Into The Future

As part of assessing the best energy sources for the future, we are looking at the pros and cons of these different energy sources.

This is our guide on Solar Energy Pros and Cons.

 

Summary – Pros & Cons Of Solar Energy

Pros

  • Solar is renewable and sustainable (not finite like fossil fuels or potentially uranium)
  • Produces no emissions while in operation
  • Is a portable form of energy
  • Can be used for small applications as well as larger applications
  • Can be used off grid
  • Can give people energy independence
  • Technology is always improving to increase capability
  • Demand is increasing, which is dropping prices to manufacture and also buy in some places
  • Solar requires fairly simple maintenance once up and running compared to nuclear for example (generally cleaning of the panel is all that is required for most smaller units)
  • Setup costs can generally be recovered over the life of solar panels
  • The typical solar panel has a decent lifespan of around 20 to 25 years
  • Solar has the benefit of setting up as many or as little panels as you like – it’s easy to set up in stages or in increments to your liking or needs … compared to a nuclear plant or a coal plant, where you have to set up a whole plant over say 6 to 8 years

Cons

  • Low power output per unit (low power density) compared to nuclear, oil, gas
  • Not suited at the moment to large scale (large city size) power supply due to various reasons
  • Price per kilowatt can be expensive in some countries, and a setup of many panels can be expensive
  • Return on investment can take time
  • Needs lots of space/land the more panels you add, unless you are installing them on buildings
  • Depends on the sun and can be intermittent
  • Not suited to places with little sun
  • Solar panels can require scarce materials to make

Solar is a pretty good option for individuals and households at the moment as long as it makes sense financially for them. But, with current solar technology, solar isn’t as suited to large scale power supply for cities as say coal, natural gas and nuclear. Technological advances will hopefully change that in the future, as well as our ability to integrate solar power better into a city’s power supply. At the moment, solar is more of a supplementary power source for the cities that use it, and isn’t as much of a primary source. As long as costs are competitive, and technology keeps advancing to increase power density/power output per unit, solar probably has one of the best long term futures as a power supply a long with wind power.

*Note – the above pros and cons are broad generalisations. Obviously there are different variables to each specific energy project that impact the final pros and cons (like new technology that reduces emissions for coal power plants just as one of many examples). Each energy project and situation (in different countries and cities) should be analysed individually. Having said that, some broad principles and patterns about the pros and cons of different energy sources tend to stay consistent too.

 

Pros Of Solar Energy

  • Is Renewable & Sustainable – not finite like fossil fuels such as coal, oil, and gas. Even nuclear may run out in the next 80 years when uranium is in low supplies. Solar energy is expected to be available for the next 5 billion years.
  • Is Clean & Carbon Emission Free While In Operation – produces no carbon dioxide or other greenhouse gases while in use, unlike fossil fuels such as coal, oil, and gas. GHGs are produced in manufacturing solar panels, but these are seen to be negligible when compared to the GHGs emitted by other energy sources.
  • Can Be Used Off The Grid, & Gives Energy Independence – solar power doesn’t require access to a power grid, so it can generate electricity anywhere panels can be installed, even poorer or less developed countries. It can be used by people free of utility companies.
  • Technology Is Improving – better technology means more efficiency. Companies and countries (like Tesla, and Germany who are the world’s solar leaders) are also working on storing excess solar energy in a cheaper way. Quantum physics research and advancements in nanotech also have the potential to greatly increase the power output of solar panels, which could lead to wider-scale use of them across the globe
  • Demand Is Increasing, & Prices Are Dropping In Some Places – companies are working to make it more affordable, and higher demand means prices come down to both produce solar energy equipment, and purchase solar power naturally.
  • Portable, Versatile & Can Be Used For Unique Application – can be used to power street lights, homes, cars, and even small electronic devices, such as your phone. You can get portable solar power panels and chargers. More solar energy uses are coming out as time progresses – making solar very versatile.
  • Low Maintenance – compared to energy like nuclear for example. Residential solar panels for example require cleaning once, maybe twice per year. The typical manufacturer’s warranty lasts anywhere from 20 to 25 years. Even though they might have higher upfront costs, you can see how easily recouped they can be over their lifespan.
  • Good Life Span – the typical solar panel set up lifespan residentially is around 20-25 years.

– renewableresourcescoalition.org

 

Cons Of Solar Energy

  • Low Power Output – compared to nuclear, oil, and gas, solar has a much lower power output per unit. Solar is unable right now to provide sufficient energy to power something like a large manufacturing plant with lots of big machinery
  • Can Be Expensive – compared to other alternative energies, the price per kilowatt can be expensive, and upfront costs can be expensive (household panels can be $1000’s of dollars). But, costs are gradually dropping.
  • Return On Investment Can Take Time – residentially, if you purchase a solar panel set up, it can take years to recoup your cost investment compared to using a utility company for use of their grid-supplied energy.
  • Needs A lot Of Space – solar panels that catch solar energy need a lot of space and land to be laid out compared to other forms of energy. The mean power density for solar is about 170 W/m2, much more than other renewable energy sources, but nowhere near the amounts of energy sources such as nuclear. It struggles to compete against alternative energy sources based on its low power density (space to power output ratio). As technology gets better, smaller panels may produce more power per square metre.
  • Depends On The Sun & Can Be Intermittent – relies on exposure to and the intensity of the sun. If the sun is not out like at night time or on overcast days or in colder climates, you’re limited in the energy you can catch. This wouldn’t be as much of an issue if there was a cheaper way to store excess solar energy. Intermittent energy isn’t a problem for nuclear or fossil fuels.
  • Right Now, It’s Not As Good For Huge Scale Energy Provision – solar isn’t as good to scale for large cities and countries right now as other energy sources. The power output is not there, and existing infrastructure isn’t built around it – meaning you lose captured solar energy that could get fed into the grid (like in countries such as China).
  • Solar Panel Cells Require Rarer Materials – Cadmium telluride and copper indium gallium selenide are examples that are not as easily found on earth as coal and fossil fuels.

– renewableresourcescoalition.org, and bettermeetsreality.com

 

Sources

1. https://www.renewableresourcescoalition.org/solar-energy-pros-cons/

2. https://www.bettermeetsreality.com/the-challenges-with-chinas-transition-from-coal-to-natural-gas-renewable-energy/

Pros & Cons Of Nuclear Energy Now & Into The Future

Pros & Cons Of Nuclear Energy

As part of assessing the best energy sources for the future, we are looking at the pros and cons of these different energy sources.

This is our guide on the Pros & Cons Of Nuclear Energy.

 

Summary – Nuclear Energy Pros & Cons

Pros

Cons

  • It’s expensive to setup and build a nuclear plant, especially in Western countries
  • Nuclear waste is very hazardous and radioactive
  • Nuclear waste must be managed and disposed of properly – this can be costly as it can’t go to a regular landfill
  • Nuclear waste and spent nuclear fuel can take hundreds of years to decompose – where in the meantime it can be a threat to the safety and health of humans, wild life and plant life
  • Uranium and nuclear are not renewable like solar or wind power for example
  • It can be expensive to decommission and handle fuel at the end of a nuclear plant’s lifetime
  • Significant nuclear accidents have happened in the past
  • Nuclear plants are a potential terrorism or security risk
  • Not a portable or small use energy source like solar panels for example – more for large scale energy generation

We probably don’t have any better overall options right now for short to medium term mass energy production than nuclear. Renewables don’t provide the level of mass energy production nuclear does right now with the technology they have and the challenges they pose in transitioning to them, and fossil fuels such as coal are high GHG emission energy sources (natural gas is better than coal and oil though in this regard).

*Note – the above pros and cons are broad generalisations. Obviously there are different variables to each specific energy project that impact the final pros and cons (like new technology that reduces emissions for coal power plants just as one of many examples). Each energy project and situation (in different countries and cities) should be analysed individually. Having said that, some broad principles and patterns about the pros and cons of different energy sources tend to stay consistent too.

 

Pros Of Nuclear Energy

  • Low Greenhouse Gases During Operation – Compared to coal, gas, and other electric-generating plants. According to the Nuclear Energy Institute (NEI), nuclear energy produces more clean-air energy than any other source. It produces 62 percent of all emission-free electricity in the United States. The large clouds you see leaving the smoke stacks are nothing more than vaporized water.
  • Incredibly High Fuel To Power Output Ratio – It has the capacity to meet city and industrial needs with just one reactor. A relatively small amount of uranium can be used to fuel a 1000 Megawatts electric plant, providing enough electricity to power a city of about half a million people. Renewable sources, such as solar and wind, provide only enough power to meet residential or office needs. They don’t yet have the capacity of nuclear to handle large-scale power needs, especially in the manufacturing world
  • Produces Inexpensive Electricity When Operational In Some Countries– cheaper than gas, coal, or any other fossil fuel plants. Uranium is also a fairly cheap fuel source
  • Over Lifetime, Nuclear Recoups Costs – the costs to make a nuclear plant can be high, but over the lifetime of a plant, costs are almost always recouped back
  • Decent Lifecycle – average lifecycle of a nuclear power plant is around 40-60 years – around the same as a coal plant (54 years average)
  • Doesn’t Rely On Fossil Fuels – so it’s not affected by the unpredictability of oil and gas costs. We won’t be depleting the Earth’s supply of resources nearly as quickly. Nuclear power requires much less fuel to produce a higher amount of energy.
  • Current Supply Of Uranium – With the current supply of uranium, it is estimated that we have at least another 80 years before supply becomes an issue. There are also other forms of uranium that can be used if needed, extending that timeline even further. This is plenty of time to find alternative sources (such as nuclear fusion, the holy grail of energy), if need be.
  • Positive Economic Impact – nuclear plants bring jobs and prosperity to local communities. According to the NEI, one new nuclear plant creates 400 to 700 permanent jobs, not to mention thousands of others during its construction. Most nuclear sites have at least 2 plants. This is comparable to just 90 jobs for a coal plant, and 50 for a natural gas plant. Each facility generates close to $500 million annually in sales of goods and services. More workers at plants means more people who need lunches and more people with money to spend.

– renewableresourcescoalition.org, and trimediaee.com

 

Cons Of Nuclear Energy

  • Not Renewable – Uranium is in limited (although currently abundant) supply. Typical renewable energy sources such as solar and wind are in infinite supply.
  • Uranium Mining & Activation Process Can Be Expensive – Uranium has to be mined, synthesized, then activated to produce energy, and it’s very expensive to go through this process.
  • Environmental Impact Of Uranium As A Fuel Source – A typical nuclear power plant generates about 20 metric tons of used nuclear fuel per year. The problem is that this spent fuel is highly radioactive and potentially dangerous.
  • Disposal of Radioactive Waste – You can’t take it to a normal landfill. It has to be carefully handled and stored (which costs a lot of money), and it requires a hefty amount of specially designed storage space
  • High Up-Front Construction Costs For Nuclear Plants – Construction of a new plant can take anywhere from 5-10 years to build, costing billions of dollars. In the East—in Korea, in China and the UAE, which is being built by the Koreans—the cost is $3,000-$4,000 per kilowatt, whereas in the West the cost is north of $8,000 per kilowatt [due to design, construction management and supply chain and workforce] (forbes.com). In Australia, nuclear is currently priced out of the energy mix compared to renewables. (reneweconomy.com.au)
  • Back End Costs Aren’t Cheap – high fuel handling and decommissioning costs.
  • Public Safety – Spent nuclear fuel takes hundreds of years to decompose before it reaches adequate levels of safety.
  • Accidents – significant accidents are actually incredibly rare, but have happened throughout history (such as the Three Mile Island meltdown in 1978, and the Chernobyl explosion in 1986). When accidents happen – they are a major problem. Casualties may not be high from nuclear accidents, but the environmental and social issues can have an impact decades later. Whilst wildlife has returned to the Chernobyl area, the area won’t be safe for human habitation for at least 20,000 years.
  • Potential Terrorism & Security Threat – with fossil fuel plants, you don’t have to worry about them being targeted by terrorists and vigilantes. Uranium used to power nuclear plants is of a different grade than weapons-grade uranium; however, it can be synthesized from it. This makes it a threat if it gets in the hands on dangerous people. Security is tight and the probability of an event is low though.
  • Not Portable Or For Small Use Applications – can only be used for powering a large grid or in special applications such as a submarine.

– renewableresourcescoalition.org, livescience.com, forbes.com, reneweconomy.com.au

 

Sources

1. https://www.renewableresourcescoalition.org/nuclear-energy-pros-cons/

2. https://trimediaee.com/blog/environmental/power-plant-past-prime/

3. https://www.livescience.com/39961-chernobyl.html

4. https://www.renewableresourcescoalition.org/solar-energy-pros-cons/

5. https://www.bettermeetsreality.com/how-much-uranium-is-left-in-the-world-on-land-in-oceans-when-will-we-run-out/

6. https://reneweconomy.com.au/nuclear-priced-out-of-australias-future-energy-equation-in-new-report-67465/

7. https://www.forbes.com/sites/jeffmcmahon/2018/10/01/3-reasons-nuclear-reactors-are-more-expensive-in-the-west-hint-its-not-regulation/#57bad5155d1a

The Pathways To Different Climate Change Temperature Scenarios (1.5, 2, 3, 4 & 4+ Degrees Celcius)

The Pathways To Different Climate Change Temperature Scenarios (1.5, 2, 3, 4 & 4+ Degrees Celcius)

You might hear about the different warming temperature scenarios for climate change.

1.5 Degrees celcius and 2 degrees get all the attention because these are often the ones identified by the IPCC and at the Paris Agreement for example.

But warming may go beyond these temperatures to 3, 4 and 4+ degrees in the future (if we don’t introduce meet the current emission targets, or introduce new emission goals and policies).

In this guide, we look at exactly what it would take to get to each of these temperatures – the pathway of quantity of emissions in what amount of time.

 

Summary – Where Are We Realistically Headed In Terms Of Global Warming In The Future?

There are several variables that impact our emissions, and level of warming in the future.

Climate models can give us a forecast based on the variables and data fed into them, but, those variables and the data can change as we do more or less to impact our emissions, and we get updated data on how the climate is responding.

From a range of studies and reports, the most likely warming range is anywhere between 2.6 to 4.8 degrees celcius above pre-industrial levels. But aggressive action by countries like China and the US immediately in terms of reducing emissions and sequestering existing atmospheric emissions could reduce that estimate.

We should note that 0.8 to 1.2 degrees of warming has already taken place since the start of industrial times.

You can read more about the forecasts and projections for climate change and global warming in the future in this guide.

 

1.5 Degrees, & 2 Degrees Are The Preferred Warming Targets, But…

  • The carbon budget is the amount of carbon dioxide emissions we can emit while still having a likely chance of limiting global temperature rise to 2 degrees celcius above pre-industrial levels.
  • This budget is roughly around 1 trillion tonnes of C02.
  • As of 2011, we’ve already gone through 52% of the budget
  • The world can stick within the budget if countries commit and stick to international C02 emissions pledges, countries pursue and introduce their own C02 reduction measures, emissions peak by 2020 and in 2040 emissions are 50% of 2020 levels and after steadily decreasing, and roughly three quarters of remaining fossil fuels stay in the ground.

BUT…

  • If emissions continue at their current rate, the world is on track to exceed the carbon budget (for 2 degrees) by around the year 2045
  • The general consensus is that it’s extremely unlikely we can still limit warming to 1.5 degrees
  • The general consensus is that we can still limit warming to 2 degrees, although it’s going to require very ambitious and immediate action from all countries to reduce emissions. 

– wri.org

 

What Are The Different Pathways Of Emissions That Lead To Different Warming Temperatures

Note – the following are just a few of many forecasts by different climate modes trying to calculate emission pathways and associated warming in the future.

They are more of a calculated guess with the information we have available right now, rather than an absolute certainty.

Carbon budgets and emission pathways have been adjusted in the past.

 

There are 4 emissions pathways we might see in the future:

  • Low Emissions, Global Temp Increases By Up To 2 Degrees Celcius – In this scenario, C02 emissions peak by 2020, and then drop 66% below 2010 levels by 2050.
  • Medium Emissions, & Global Temp Increases By Up To 2.9 Degrees Celcius – In this scenario, C02 emissions peak by 2040, but still rise 19% above 2010 levels by 2050. By the year 2056, the carbon budget is exhausted, locking in a 2 degrees increase.
  • High Emissions, & Global Temp Increases By Up To 3.7 Degrees Celcius – In this scenario, C02 emissions peak by 2080, but still rise 34% above 2010 levels by 2050. By the year 2057, the carbon budget is exhausted, locking in a 2 degrees increase.
  • Highest Emissions, & Global Temperature Increases By Up To 4.8 Degrees Celcius  – In this scenario, annual C02 emissions continue to rise through 2100, rising 108% above 2010 levels by 2050. By the year 2045, the carbon budget is exhausted, locking in a 2 degrees increase.

– You can read more, including the impacts on earth, humans, animals and the environment at each of these scenarios and pathways at https://www.wri.org/ipcc-infographics

 

On 6 October 2018, the IPCC Summary For Policymakers Special Report was produced.

This report outlines the following for 1.5 degrees celcius warming:

  • The amount of C02 that can be produced in every year into the future, and the amount of black carbon, methane and nitrous oxide
  • The characteristics of four illustrative model pathways to limit warming to 1.5 degrees celcius

You can check it out at http://report.ipcc.ch/sr15/pdf/sr15_spm_final.pdf

 

Sources

1. https://www.wri.org/ipcc-infographics

2. http://report.ipcc.ch/sr15/pdf/sr15_spm_final.pdf

The Difference In Impact At 1.5, 2, 3, 4 & 4+ Degrees Celcius For Climate Change, & Global Warming

The Difference In Impact At 1.5, 2, 3, 4 & 4+ Degrees For Climate Change, & Global Warming

You might hear about how global warming has more of an impact as the world get’s warmer.

What we’ve done is put together a guide outlining the potential different impacts at different temperature levels.

You can see below what might be the difference at 1.5, 2, 3, 4 and 4+ degrees celcius.

 

Summary – Difference In Impact On The World For Each Degree Of Global Warming

  • Some changes brought about by global warming can be positive, whilst others can be negative
  • Global warming and climate change can lead to changes in sea level rise, temperature of the ocean, ocean acidity, ice in the Arctic, thawing of permafrost, size of glaciers, snow in the northern hemisphere and around the world, daily temperature, exposure to heat waves, how warm it is over the land, cold extremes over land, average rainfall, number of consecutive dry days, number of consecutive days with rainfall, intensity of rainfall, frequency of rainfall extremes over land, average river flows, average drought length, population introduced to water scarcity, population exposed to drought, number of tropical cyclones, number of 4 and 5 category cyclones, coastal areas flooded, crop yields for wheat, crop yields for maize, crop yields for soy, crop yields for rice, livestock activity, different organisms, plants, and animal species losing their climatic range, average warming across drylands and humid lands, global per capita GDP and other GDP related factors, transmission of diseases like malaria, and other human health related factors
  • These changes can happen worldwide or in specific geographic locations and regions

 

The Difference In Impact On The World At 1.5, 2, 3, 4 & 4+ Degrees Celcius Global Warming

CarbonBrief.org Interactive Chart (1.5, 2, 3 and 4.5C differences)

Carbon Brief has extracted data from around 70 peer-reviewed climate studies to show how global warming is projected to affect the world and its regions.

At different temperature levels, you can see the impact of temperature levels on:

  • Oceans, Ice, Rainfall & Precipitation, Drought, Storms & Flooding, Crops, Nature/Animals, Plants, The Economy, Health
  • The World/Globally, Europe, The Americas, The Caribbean & Small Islands, Africa, Asia, China, Australasia

Some of the things to note are:

Globally

  • Sea level rise by 2100 – 48cm at 1.5C (degrees celcius), and 56cm at 2C
  • Sea level rise by 2300 – 59cm at 1.5C, and 81cm at 2C
  • Increase in global marine heatwave days per year – x16 at 1.5C , x23 at 2C, x41 at 3.5C
  • Ocean Acidity by 2050 – 17% at 1.5C, 29% at 2C
  • Ocean Acidity by 2100 – 9% at 1.5C, 24% at 2C
  • Ocean Acidity by 2300 – 6% at 1.5C, 16% at 2C
  • There are increases in ice free Arctic summers as temperature increases
  • There are increases in areas of thawed permafrost as temperature increases
  • There are increases in glacier mass loss as temperature increases
  • Northern hemisphere snow extent in 2080’s decreases as temperature increases
  • Global areas seeing reductions in maximum monthly snow storage from 100 to 30% increases
  • Annual maximum daily temperature – increases by 1.7C at 1.5C, and 2.6C at 2C
  • Number of hot days – increases by 16% at 1.5C, and 25% at 2C
  • Warm spell duration – 17 days at 1.5C, 35 days at 2C
  • Global exposure to heatwaves – population facing at least one severe or extreme heatwave every 5 or 20 years increases in %
  • Frequency of warm extremes over land – increases from 129% at 1.5C, and 343% at 2C
  • Frequency of cold extremes over land – increases from 54% at 1.5C, and 82% at 2C
  • Average rainfall – increases from 2% at 1.5C, and 4% at 2C
  • Consecutive dry days – decreases from 2 at 1.5C, and 3 at 2C
  • Maximum consecutive 5 day precipitation – increases from 4mm at 1.5C, and 6mm at 2C
  • Rainfall intensity – an increase of 2% at 1.5C, and 4% at 2C
  • Frequency of rainfall extremes over land – increases 17% at 1.5C, and 36% at 2C
  • There is a change in average river flows by 2100
  • Average drought length (months) – increased by 2 at 1.5C, 4 at 2C, and 10 at 3C
  • Population introduced to water scarcity – increased by 271 million at 1.5C, and 388 million at 2C
  • Global population exposed to severe drought – increased 132.5 million at 1.5C, and 194.5 million at 2C
  • Global annual number of total tropical cyclones – decreases by 0.9 at 1.5C, and 4.1 at 2C
  • Global annual number of Category 4 cyclones – increases by 2.1 at 1.5C, and 1.2 at 2C
  • Global annual number of Category 5 cyclones – increases by 1.4 at 1.5C, and 1.2 at 2C
  • Global population flooded in coastal areas by 2055 – increases by 28 million a year at 1.5C, to 30 million a year at 2C
  • Global population flooded in coastal areas by 2095 – increases by 60 million a year at 1.5C, to 72 million a year at 2C
  • Global population flooded in coastal areas by 2295 – increases by 136 million a year at 1.5C, to 162 million a year at 2C
  • Average crop yield change by 2100 for wheat – decreases 6% at 1.5C, and 9% at 2C
  • Average crop yield change by 2100 for maize – decreases 5% at 1.5C, and 4% at 2C
  • Growing season length – increase by 5 days at 1.5C, and 8 days at 2C
  • Crop yields over existing farm land for wheat (global) – increases 2% at 1.5C, and 0% change at 2C
  • Crop yields over existing farm land for maize (global) – decreases 1% at 1.5C, and 6% at 2C
  • Crop yields over existing farm land for soy (global) – increases 7% at 1.5C, and 1% at 2C
  • Crop yields over existing farm land for rice (global) – increases 7% at 1.5C, and 7% at 2C
  • Crop yields over existing farm land for wheat (tropics) – decreases 9% at 1.5C, and 16% at 2C
  • Crop yields over existing farm land for soy (tropics) – decreases 3% at 1.5C, and 6% at 2C
  • Crop yields over existing farm land for maize (tropics) – increases 6% at 1.5C, and 7% at 2C
  • Crop yields over existing farm land for rice (tropics) – increases 6% at 1.5C, and 6% at 2C
  • Proportion of invertebrates losing more than 50% of their climatic range – 6% at 1.5C, 18% at 2C, 68% at 4.5C
  • Proportion of vertebrates losing more than 50% of their climatic range – 4% at 1.5C, 8% at 2C, 44% at 4.5C
  • Proportion of plants losing more than 50% of their climatic range – 8% at 1.5C, 16% at 2C, 67% at 4.5C
  • Proportion of insects losing more than 50% of their climatic range – 6% at 1.5C, 18% at 2C, 67% at 4.5C
  • Proportion of mammals losing more than 50% of their climatic range – 4% at 1.5C, 8% at 2C, 41% at 4.5C
  • Proportion of birds losing more than 50% of their climatic range – 2% at 1.5C, 6% at 2C, 40% at 4.5C
  • Proportion of butterflies and moths losing more than 50% of their climatic range – 4% at 1.5C, 10% at 2C, 58% at 4.5C
  • Proportion of dragonflies and damselflies losing more than 50% of their climatic range – 1% at 1.5C, 2% at 2C, 21% at 4.5C
  • Average warming across drylands – increase of 2.4 to 3 degrees at 1.5C, and increase of 3.2 to 4 degrees at 2C
  • Average warming across humid lands – increase of 1.8 to 2 degrees at 1.5C, and increase of 2.4 to 2.6 degrees at 2C
  • Global per capita GDP in 2100 – decrease of 8% at 1.5C, and decrease of 13% at 2C
  • Annual flood damage losses from sea level rise – $10.2 trillion at 1.5C, and $11.7 trillion at 2C
  • Global impact on GDP of energy demand for heating and cooling – decrease of 0.05% at 1.5C, 0.19% at 2C, and 0.9% at 4C
  • Suitability of drylands for malaria transmission – increase 19% at 1.5C, and 27% at 2C
  • Suitability of humid lands for malaria transmission – increase 6% at 1.5C, and 8% at 2C

View the full interactive chart at https://interactive.carbonbrief.org/impacts-climate-change-one-point-five-degrees-two-degrees/

 

IPCC Summary For Policymakers, 6 October 2018 (1.5 and 2C differences)

On the 6th October 2018, a special report was brought out on the impacts of global warming of 1.5 °C above pre-industrial levels.

Part of the report focussed on the potential differences of impacts between 1.5 and 2 degrees celcius warming/temperature change.

Some of those potential differences were (between 1.5°C and 2°C):

  • Overall – Climate-related risks for natural and human systems are higher for global warming of 1.5°C than at present, but lower than at 2°C (high confidence). These risks depend on the magnitude and rate of warming, geographic location, levels of development and vulnerability, and on the choices and implementation of adaptation and mitigation options (high confidence)
  • Regional climate characteristics – Climate models project robust differences in regional climate characteristics between present-day and global warming of 1.5°C, and between 1.5°C and 2°C. These differences include increases in: mean temperature in most land and ocean regions (high confidence), hot extremes in most inhabited regions (high confidence), heavy precipitation in several regions (medium confidence), and the probability of drought and precipitation deficits in some regions (medium confidence).
  • Extreme hot days – extreme hot days in mid-latitudes warm by up to about 3°C at global warming of 1.5°C and about 4°C at 2°C (high confidence)
  • Extreme cold nights – extreme cold nights in high latitudes warm by up to about 4.5°C at 1.5°C and about 6°C at 2°C (high confidence)
  • Number of hot days – The number of hot days is projected to increase in most land regions, with highest increases in the tropics (high confidence).
  • Risks from droughts and precipitation deficits – risks from droughts and precipitation deficits are projected to be higher at 2°C compared to 1.5°C global warming in some regions (medium confidence).
  • Risks from heavy precipitation events – risks from heavy precipitation events are projected to be higher at 2°C compared to 1.5°C global warming in several northern hemisphere high-latitude and/or high-elevation regions, eastern Asia and eastern North America (medium confidence).
  • Heavy precipitation associated with tropical cyclones –  is projected to be higher at 2°C compared to 1.5°C global warming (medium confidence).
  • Projected changes in heavy precipitation – there is generally low confidence in projected changes in heavy precipitation at 2°C compared to 1.5°C in other regions.
  • Heavy precipitation when aggregated at global scale – is projected to be higher at 2.0°C than at 1.5°C of global warming (medium confidence).
  • Fraction of the global land area affected by flood hazards – As a consequence of heavy precipitation, the fraction of the global land area affected by flood hazards is projected to be larger at 2°C compared to 1.5°C of global warming (medium confidence).
  • Global mean sea level rise – By 2100, global mean sea level rise is projected to be around 0.1 metre lower with global warming of 1.5°C compared to 2°C (medium confidence). Sea level will continue to rise well beyond 2100 (high confidence), and the magnitude and rate of this rise depends on future emission pathways. Model-based projections of global mean sea level rise (relative to 1986-2005) suggest an indicative range of 0.26 to 0.77 m by 2100 for 1.5°C global warming, 0.1 m (0.04-0.16 m) less than for a global warming of 2°C (medium confidence).
  • Risks associated with sea level rise – are higher at 2°C compared to 1.5°C
  • Impacts on land based biodiversity and ecosystems – On land, impacts on biodiversity and ecosystems, including species loss and extinction, are projected to be lower at 1.5°C of global warming compared to 2°C.
  • Impacts on coastal and water based biodiversity and ecosystems – Limiting global warming to 1.5°C compared to 2°C is projected to lower the impacts on terrestrial, freshwater, and coastal ecosystems and to retain more of their services to humans (high confidence).
  • Species losing climatic range – Of 105,000 species studied,9 6% of insects, 8% of plants and 4% of vertebrates are projected to lose over half of their climatically determined geographic range for global warming of 1.5°C, compared with 18% of insects, 16% of plants and 8% of vertebrates for global warming of 2°C (medium confidence).
  • Other biodiversity related risks – Impacts associated with other biodiversity-related risks such as forest fires, and the spread of invasive species, are lower at 1.5°C compared to 2°C of global warming (high confidence).
  • Transformations of ecosystems – Approximately 4% (interquartile range 2–7%) of the global terrestrial land area is projected to undergo a transformation of ecosystems from one type to another at 1ºC of global warming, compared with 13% (interquartile range 8–20%) at 2°C (medium confidence). This indicates that the area at risk is projected to be approximately 50% lower at 1.5°C compared to 2°C (medium confidence).
  • Thawing of permafrost – Limiting global warming to 1.5°C rather than 2°C is projected to prevent the thawing over centuries of a permafrost area in the range of 1.5 to 2.5 million km2 (medium confidence).
  • Ocean temperature – Limiting global warming to 1.5°C compared to 2ºC is projected to reduce increases in ocean temperature as well as associated increases in ocean acidity and decreases in ocean oxygen levels (high confidence).
  • Risks to marine biodiversity – limiting global warming to 1.5°C is projected to reduce risks to marine biodiversity, fisheries, and ecosystems, and their functions and services to humans, as illustrated by recent changes to Arctic sea ice and warm water coral reef ecosystems (high confidence)
  • Sea ice free ocean – There is high confidence that the probability of a sea-ice-free Arctic Ocean during summer is substantially lower at global warming of 1.5°C when compared to 2°C. With 1.5°C of global warming, one sea ice-free Arctic summer is projected per century. This likelihood is increased to at least one per decade with 2°C global warming.
  • Other ocean related risks – Global warming of 1.5°C is projected to shift the ranges of many marine species, to higher latitudes as well as increase the amount of damage to many ecosystems. It is also expected to drive the loss of coastal resources, and reduce the productivity of fisheries and aquaculture (especially at low latitudes). The risks of climate-induced impacts are projected to be higher at 2°C than those at global warming of 1.5°C (high confidence). Coral reefs, for example, are projected to decline by a further 70–90% at 1.5°C (high confidence) with larger losses (>99%) at 2ºC (very high confidence). The risk of irreversible loss of many marine and coastal ecosystems increases with global warming, especially at 2°C or more (high confidence).
  • Ocean acidification – The level of ocean acidification due to increasing CO2 concentrations associated with global warming of 1.5°C is projected to amplify the adverse effects of warming, and even further at 2°C, impacting the growth, development, calcification, survival, and thus abundance of a broad range of species, e.g., from algae to fish (high confidence).
  • Fisheries and aquaculture – Impacts of climate change in the ocean are increasing risks to fisheries and aquaculture via impacts on the physiology, survivorship, habitat, reproduction, disease incidence, and risk of invasive species (medium confidence) but are projected to be less at 1.5ºC of global warming than at 2ºC. One global fishery model, for example, projected a decrease in global annual catch for marine fisheries of about 1.5 million tonnes for 1.5°C of global warming compared to a loss of more than 3 million tonnes for 2°C of global warming (medium confidence).
  • Human and social related risks – Climate-related risks to health, livelihoods, food security, water supply, human security, and economic growth are projected to increase with global warming of 1.5°C and increase further with 2°C.
  • Populations and regions at risk – Populations at disproportionately higher risk of adverse consequences of global warming of 1.5°C and beyond include disadvantaged and vulnerable populations, some indigenous peoples, and local communities dependent on agricultural or coastal livelihoods (high confidence). Regions at disproportionately higher risk include Arctic ecosystems, dryland regions, small-island developing states, and least developed countries (high confidence). Poverty and disadvantages are expected to increase in some populations as global warming increases; limiting global warming to 1.5°C, compared with 2°C, could reduce the number of people both exposed to climate-related risks and susceptible to poverty by up to several hundred million by 2050 (medium confidence).
  • Human health – Any increase in global warming is projected to affect human health, with primarily negative consequences (high confidence). Lower risks are projected at 1.5°C than at 2°C for heat-related morbidity and mortality (very high confidence) and for ozone-related mortality if emissions needed for ozone formation remain high (high confidence). Urban heat islands often amplify the impacts of heatwaves in cities (high confidence). Risks from some vector-borne diseases, such as malaria and dengue fever, are projected to increase with warming from 1.5°C to 2°C, including potential shifts in their geographic range (high confidence).
  • Crops and livestock – Limiting warming to 1.5°C, compared with 2ºC, is projected to result in smaller net reductions in yields of maize, rice, wheat, and potentially other cereal crops, particularly in subSaharan Africa, Southeast Asia, and Central and South America; and in the CO2 dependent, nutritional quality of rice and wheat (high confidence). Reductions in projected food availability are larger at 2ºC than at 1.5°C of global warming in the Sahel, southern Africa, the Mediterranean, central Europe, and the Amazon (medium confidence). Livestock are projected to be adversely affected with rising temperatures, depending on the extent of changes in feed quality, spread of diseases, and water resource availability (high confidence)
  • Water stress – Depending on future socioeconomic conditions, limiting global warming to 1.5°C, compared to 2°C, may reduce the proportion of the world population exposed to a climate-change induced increase in water stress by up to 50%, although there is considerable variability between regions (medium confidence). Many small island developing states would experience lower water stress as a result of projected changes in aridity when global warming is limited to 1.5°C, as compared to 2°C (medium confidence).
  • Economic Growth – Risks to global aggregated economic growth due to climate change impacts are projected to be lower at 1.5°C than at 2°C by the end of this century10 (medium confidence). This excludes the costs of mitigation, adaptation investments and the benefits of adaptation. Countries in the tropics and Southern Hemisphere subtropics are projected to experience the largest impacts on economic growth due to climate change should global warming increase from 1.5°C to 2 °C (medium confidence).
  • Compound and multiple risks – . Exposure to multiple and compound climate-related risks increases between 1.5°C and 2°C of global warming, with greater proportions of people both so exposed and susceptible to poverty in Africa and Asia (high confidence). For global warming from 1.5°C to 2°C, risks across energy, food, and water sectors could overlap spatially and temporally, creating new and exacerbating current hazards, exposures, and vulnerabilities that could affect increasing numbers of people and regions (medium confidence).
  • Adaptation Needs – Most adaptation needs will be lower for global warming of 1.5°C compared to 2°C (high confidence)

You can read more at http://report.ipcc.ch/sr15/pdf/sr15_spm_final.pdf

 

Further Reading

  • https://www.wri.org/ipcc-infographics (some impacts at 2, 2.9, 3.7 and 4.8 degrees celcius warming)
  • http://globalwarming.berrens.nl/globalwarming.htm (degree by degree explanation of what happens when the earth warms – 1, 2, 3, 4, 5, and 6 degrees of warming)
  • https://www.dw.com/en/the-world-at-3-degrees-what-it-means-for-five-cities/a-41392444 (the world at 3 degrees, and what it means for 5 cities)
  • https://www.theguardian.com/cities/ng-interactive/2017/nov/03/three-degree-world-cities-drowned-global-warming (a 3 degrees world and which cities will be drowned by it)
  • http://www.global-greenhouse-warming.com/3-degrees.html (3 degrees of warming)
  • https://www.greenfacts.org/en/impacts-global-warming/l-2/1.htm (impacts of 4 degrees global warming)
  • https://bigthink.com/strange-maps/what-the-world-will-look-like-4degc-warmer (what the world will look lke 4 degrees warmer)
  • https://theconversation.com/a-matter-of-degrees-why-2c-warming-is-officially-unsafe-42308 (why 2 degrees celcius warming might be considered unsafe)

 

What Is The Forecast For The Future & The Warming Of The World?

You can check out the forecasts and projections for global warming and climate change up to the year 2100.

 

Sources

1. https://interactive.carbonbrief.org/impacts-climate-change-one-point-five-degrees-two-degrees/ (Interactive Chart)

2. http://report.ipcc.ch/sr15/pdf/sr15_spm_final.pdf (IPCC Summary For Policymakers, 6 October 2018)

3. http://globalwarming.berrens.nl/globalwarming.htm

4. https://www.dw.com/en/the-world-at-3-degrees-what-it-means-for-five-cities/a-41392444

5. https://www.theguardian.com/cities/ng-interactive/2017/nov/03/three-degree-world-cities-drowned-global-warming

6. http://www.global-greenhouse-warming.com/3-degrees.html

7. https://www.greenfacts.org/en/impacts-global-warming/l-2/1.htm

8. https://bigthink.com/strange-maps/what-the-world-will-look-like-4degc-warmer

9. https://www.wri.org/ipcc-infographics

10. https://theconversation.com/a-matter-of-degrees-why-2c-warming-is-officially-unsafe-42308 

11. https://www.wri.org/resources/data-visualizations/infographic-global-carbon-budget

Why It Can Be Hard To Forecast/Predict Climate Change Into The Future (Uncertainties & Variables To Consider)

3 Difficulties With Projecting/Forecasting Climate Change & Global Warming Into The Future

There’s several factors that can present uncertainty when predicting the exact future of climate change, and in this guide, we outline and explain those factors.

 

What Is It We Might Be Uncertain About? 

Mainly – we might be uncertain about the rate of warming in the future.

But, we can also be uncertain (to an extent) about the exact impact this warming will have on different parts of the world, or the events that are made more likely as a result of climate change (or can be linked directly to it).

For example, if we have a severe drought somewhere in the future – to what extent did climate change and a warming trend caused by human greenhouse gas emission have something to do with it? … There can be significant debate about this because it can be easy to link every new or extreme event to human induced climate change.

One example is the inconclusive science on linking climate change with El Niño events (blogs.ei.columbia.edu)

But, on the other hand, there is some data based on climate modelling that the recent severe drought in Cape Town was made 3 times more likely by current climate change conditions, and will be made another 3 times more likely in the future if global temperature increase another 1 degrees celcius. Read more about this at https://theconversation.com/global-warming-has-already-raised-the-risk-of-more-severe-droughts-in-cape-town-107625)

Overall, a good scientist would probably admit what they think are uncertainties to do with things such as ancient climate data (compared to new climate data gathered with new technology), and climate models that give projections, forecasts and results based on the calculations, formulas, data and assumptions fed into them (having said that – these data sources and models give us the best way at the moment of making up to date conclusions on the state and future of the climate until we have a better way of understanding a complex climate system).

Uncertainties though don’t remove the risk that climate change caused primarily by humans could present.

 

Factors That Can Add Uncertainty To Forecasting Climate Change In The Future

Precise forecasts for greenhouse gas emissions, and particularly carbon dioxide emissions, are hard to make due to factors such as economic activity, price of fossil fuels, what happens in the electricity and transport industries, government policy developments, whether there are improvements in energy efficiency + more.

 

Here are some other specific reasons…

 

1. We Don’t Know What Future Emissions Are Going To Be – We Can Only Plot Different Potential Emissions Pathways Based On Potential Emissions Scenarios

Because of social, economic and governmental factors (policies and regulations). It depends on how the global economy develops and how society’s production and consumption of energy changes in the coming decades + how governments handle climate policy. Population growth and how many people end up being on earth in 2050 and 2100 are also big variables that impact future emissions.

 

  • A good example of uncertain C02 emissions heading into the future is in China.
  • China currently relies heavily on coal as a fuel source in many ways.
  • In 2016 for example, in terms of Giga tonnes of C02 emissions in China, Coal was responsible for 7.17Gt, Oil 1.38Gt, Gas 0.395Gt, Cement 1.2Gt and 0 from Gas Flaring
  • Having said that, As of 2017 in China, renewables were generating 5.3% of China’s electricity supply
  • So, China has begun to invest heavily in renewable energy, and they also want to transition to gas
  • BUT, there are many challenges with the transition from coal to gas and renewable energy in China. These challenges are across many different parts of the country at all levels
  • How quickly and smoothly that transition takes place will have a major impact on China’s C02 emissions going into the future.
  • Factors in all areas such as social, political, economic, technological, environmental and more all play a part

– bettermeetsreality.com

 

2. We Can’t Say For Certain How Earth’s Feedback Loop Will React In Full, Or How One Feedback Event Will Interact With Another

Feedback loops can be complex and difficult to predict in terms of whether and how they will amplify or diminish initial warming. With current understanding of the complexities of how climate feedbacks operate, there is a range of possible outcomes, even for a particular scenario of CO2 emissions. So, when forecasting, depending on what forecast model or program is used, and the factors and calculations or assumptions made – you may get different outcomes and projections for the same emission data set.

 

  • Climate change does not just involve warming and one isolated side effect occurring. It actually involves feedback and feedback loops
  • Warming leads to further effects (feedbacks) that either amplify or diminish the initial warming
  • One of the biggest feedback amplifiers is water vapor
  • Water vapor for example may have a feedback effect on cloud cover
  • 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.

– royalsociety.org, science.org.au, and Wikipedia.org

 

With natural feedbacks, what can happen is, we can eventually get to a point where it won’t matter anymore the amount of emissions we put out. If we reach a point where feedbacks continue to amplify the warming already caused, it becomes a compounding effect where the natural feedback cycle will warm the earth on it’s own – an obviously undesirable scenario. We absolutely want to prevent this risk from being a possibility – which is why some people want to cut emissions to zero and start sequestering carbon as soon as possible.

It’s hard to know when we will reach this point, or quantify the size of the amplification that might take place though.

 

3. There Is Some Debate Over How Sensitive Earth’s Climate Is To Emissions

Sensitivity can impact forecasts and also the outcome of different emission pathways, and not everyone agrees on exactly how sensitive the earth’s climate is to emissions.

 

4. The Impact Of Natural Forcings On Climate Can Be Unpredictable Over Shorter Time Spans Of Up To Around A Decade (Which Means We May Only Be Able To See Their Impact By Looking Back On Data Over Longer Timespans)

In any given short period or over a decade (but not over the long term such as a century or more), natural warming factors like volcanic eruptions can have a much larger impact on climate than usual. These natural factors can throw out climate forecasts and data in the short term.

Over timescales of a decade or so, natural variability can modulate the effects of an underlying trend in temperature. What this means is that although natural factors are highly unlikely to play a role in long term warming trends and the data scientists get from these trends, they can impact what data and impacts scientists are seeing within a short term time span of around a decade. What this really means is that you have to look at data over several decades, or 50 years to a century, to get an accurate idea of the trend that is going on.

 

  • Scientists routinely test whether purely natural changes in the Sun, volcanic activity, or internal climate variability could plausibly explain the patterns of change they have observed in many different aspects of the climate system.
  • These analyses have shown that the observed climate changes of the past several decades cannot be explained just by natural factors.
  • BUT, short term warming or cooling may occur via natural factors

– bettermeetsreality.com

 

  • [recently] … there was a strong El Niño, the periodic climate phenomenon that makes the tropical climate hotter and drier, adding to CO2 releases from forests. But how much, we actually don’t know [because of the unpredictability of natural forcings]
  • [to add to this] we know remarkably little … about how much CO2 healthy growing forests, vegetation, and soils absorb or about emissions from land use changes such as deforestation … may be larger than generally assumed. Scientists don’t even agree whether, taken overall, tropical forests are a sink or a source of atmospheric CO2
  • … That means that, at present, there is no way that atmospheric modellers will be able to verify whether one set of Paris emissions targets are working before the next set are introduced. 

– e360.yale.edu

 

5. Global Climate Change Is Different To Regional Climate Change

Predicting climate change on the global level is different to regional (smaller) areas. We may not know for sure how a particular state or region is going to change in the future. The general thought is that areas with low rainfall will experience even less rainfall, and areas with more rainfall will experience increased rainfall, but it’s not known for sure. The same goes for traditionally hot and cold climates. Regional climate change may turn out to be different than predictions, whereas overall temperature change might be able to be predicted with more accuracy.

 

  • It is very difficult to tell in detail how climate change will affect individual locations, particularly with respect to rainfall. Even if a global change were broadly known, its regional expression would depend on detailed changes in wind patterns, ocean currents, plants, and soils.

– science.org.au

 

6. Other Factors Impact Climate Change In An Uncertain Way

Such as cloud formation, but also include water vapour and ice feedbacks, ocean circulation changes, and natural cycles of greenhouse gases.  All these things can impact climate change or the rate of warming.

 

7. Past Or Historical Climate Data Can Be Incomplete Or Have Inaccuracies

Such as rock sediment samples or ice cores or other means of historical earth or climate data. If this data is used in current models or projection, it can make some factors to do with projection more uncertain – although, in general it is thought historical/past data largely supports model calculations. Making conclusions from ice cores, rock sediment samples and other ancient data can be hard to draw accurate or solid conclusions from in terms of historic climate patterns.

 

8. Climate Models (Used For Climate Calculations, Simulation Or Forecasting) Might Be Questioned In Certain Ways 

Different climate models have different levels of complexity and simplicity, make different assumptions, use different data, and so on.

There can be some uncertainty over the result a specific climate model produces, depending on how that model is set up and the data fed into it, or even between models.

Models are always being made more accurate with tweaks, changes and improvements though.

 

9. The Climate System Can Show Abrupt Changes Sometimes

Abrupt climate transitions have occurred in Earth’s history (with hard to predict timing and likelihood). Abrupt climate change is always a possibility, although a low one.

 

10. We Want To Keep Each Country Accountable For Emissions – But, There Is Some Questioning Over The Emission Data Reported By Some Countries (Which Impacts Current & Future Rates Of Warming Forecasting, & Things Like Carbon Budgets)

Emission data from all countries can be used to forecast future emission pathways and warming scenarios, as well as rough carbon budgets.

Some people question the emission data provided by some countries such as China (saying it is under reported or inaccurate).

Under reporting emissions data can obviously have a big impact on how we forecast warming going forward and what emissions allowances we might have left.

 

  • [there is] no sure way of independently verifying whether national governments are telling the truth about their own emissions or of knowing by how much global anthropogenic emissions are actually increasing.
  • [this presents problems with the data we currently have, as well as forecasts and budgets for the future]

– e360.yale.edu

 

11. Not All Coal Emits The Same Amount Of C02

For example, the coal in China doesn’t emit as much C02 as in other parts of the world.

This becomes a problem if you treat all fossil fuels as the same, as it can impact the emissions data you are assuming from human emissions from fossil fuels (it could increase or decrease the carbon budget remaining for example).

 

  • Chinese coal generally has a much lower carbon content than typical coal burned around the world. So every ton burned releases less CO2 — on average 40 percent lower than the values used in calculations by the UN’s Intergovernmental Panel on Climate Change (IPCC)

– e360.yale.edu

 

Further Resources That Outline Information About Uncertainties

  • http://www.probeinternational.org/RS_ClimateChange_SummaryofScience.pdf – aspects of climate change that have a wide consensus but there is debate upon, aspects that are not well understood, and developments we are making with climate science
  • https://www.skepticalscience.com/print.php?r=282 – summary of the above Royal Society report
  • https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/basics-of-climate-change/ – discusses how complex processes and feedbacks shape our climate, how we can’t predict future emissions, how there’s a range of scenarios for each C02 emission path, and how over the timespan of a decade or so, natural variability can modulate the effects of an underlying trend in temperature. 
  • http://www.ox.ac.uk/research/research-impact/how-be-certain-uncertainty-climate-and-weather-forecasts – explains how climate models work and how models contain a degree of uncertainty. Also, explains how scientists are trying to quantify the amount of uncertainty in the models
  • https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.2011.0161 – summarises how we might look to represent uncertainty in climate science, how models have uncertainty, and how there can be uncertainty in projections of climate change
  • https://www.forbes.com/sites/rrapier/2018/11/29/indisputable-facts-on-climate-change/#27796bb43d05 – says there is uncertainty in climate modelling, but this uncertainty is sometimes used by critics to overstate the uncertainty about the possible outcomes.
  • https://www.climatechangeinaustralia.gov.au/en/climate-campus/modelling-and-projections/projecting-future-climate/uncertainty-and-confidence/ – explains how we achieve confidence in climate science, where the uncertainty lies, and how scientists deal with and address uncertainty in their processes
  • https://skepticalscience.com/how-exxon-overstates-uncertainty-climate-science.html – outlines how to interpret some climate models and graphs, and the types of uncertainties they might have
  • https://skepticalscience.com/climate-sensitivity-uncertainties-concern.html – outlines the uncertainty of climate sensitivity to doubling emissions from pre industrial levels
  • https://skepticalscience.com/how-much-15C-budget-left.html – discusses the sensitivity of the climate to CO2 emissions
  • https://www.carbonbrief.org/analysis-why-the-ipcc-1-5c-report-expanded-the-carbon-budget – uncertainties that surround the revised 1.5 degrees carbon budget
  • https://www.wri.org/blog/2018/10/according-new-ipcc-report-world-track-exceed-its-carbon-budget-12-years – outlines the uncertainties to do with the carbon budget, and other climate science uncertainties
  • https://www.carbonbrief.org/analysis-how-much-carbon-budget-is-left-to-limit-global-warming-to-1-5c – more summaries of the uncertainties to do with carbon budgeting and overall climate science uncertainties

 

Despite The Uncertainties, This Is What We Do Know… 

  • We know what the global temperature rise has been since the start of industrial times (about 0.8 degrees celcius since 1880)
  • We know that humans have burnt a lot of fossil fuels in this time (causing an increase in carbon ppm), especially since 1950/60, and emissions like carbon dioxide and other greenhouse gases have a warming effect on Earth
  • And lastly, we know that our best idea right now (based on the information we have) is to minimise the risk associated with future global warming, is to reduce future greenhouse gas emissions (in electricity production production, in transport (small to medium sized vehicles) and agriculture, land and forestry), and try sequester/absorb the existing gases in the atmosphere as quickly as possible

 

There is a good summary of what we do know for sure about climate change at https://www.forbes.com/sites/rrapier/2018/11/29/indisputable-facts-on-climate-change/#27796bb43d05 

 

Climate Science & Modelling/Forecasting Is Always Improving & Developing With What It Is Able To Do

  • … several major issues make it impossible to give precise estimates of how global or regional temperature trends will evolve decade by decade into the future.
  • [But,] Scientists have made major advances in the observations, theory, and modelling of Earth’s climate system; and these advances have enabled them to project future climate change with increasing confidence.

– royalsociety.org

 

We are always closing gaps in uncertainties and coming up with better ways to model climate change, interpret past data, observe current climate patterns and events, and assess overall climate change.

Climate predictions and understanding can only get better in the future with greater understanding, technology and advancements.

 

What Are The Current Projections For Climate Change In The Future?

Taken together, all model projections indicate that Earth will continue to warm considerably more over the next few decades to centuries.

The question is precisely how much, and in what time span (and how do we want to respond to it socially and economically).

 

  • One forecast is that if there were no technological or policy changes to reduce emission trends from their current trajectory, then further warming of [between] 2.6 to 4.8 °C (4.7 to 8.6 °F) in addition to that which has already occurred would be expected during the 21st century.
  • Projecting what those ranges will mean for the climate experienced at any particular location is a challenging scientific problem, but estimates are continuing to improve as regional and local-scale models advance.

– royalsociety.org

 

The Uncertainty In Climate Change Forecasting Does Not Remove Potential Future Risks We Might Face 

  • Uncertainty about the climate system does not decrease risk associated with greenhouse gas emissions, because it works in both directions: climate change could prove to be less severe than current estimates, but could also prove to be worse.
  • Even if future changes from greenhouse gas emissions are at the low end of the expected range, a high-emissions pathway would still be enough to take the planet to temperatures it has not seen for many millions of years

– science.org.au

 

    • No-one acknowledges the limitations of computer climate models more readily than modellers themselves, who will frequently bemoan the roughness of the resolution at which they have to work given the tools available.
    • But does this mean that we have to wait for complete certainty before acting? [No]
    • Scientists have, for example, known that greenhouse gases warm the planet since the 1860s. The observation that the globe is warming is supported by numerous independent lines of evidence and is not reliant on outputs from climate models.

 

  • Are you willing to accept the risk [of severe weather and environmental events happening]?
  • In such a complex system, our knowledge of many parts of the climate system is unlikely to ever be definitive. However, it’s clearly the case that even uncertain answers can help us to work out the scale of the risks we face from climate change, and how to manage them.

– carbonbrief.org

 

To put that another way, even if there are some uncertainties, it doesn’t remove the fact that we know the earth is warming, we are observing severe weather events, and we know that the carbon dioxide we are emitting causes the earth to warm.

There is a risk associated with the things we do know (such as a scenario where it will no longer matter if we decrease emissions and the earth will warm itself endlessly with amplifying feedback processes), and there is a responsibility to try to minimise that risk by reducing our emissions as fast as possible, and sequestering carbon dioxide from the atmosphere.

 

Sources

1. royalsociety.org/topics-policy/projects/climate-change-evidence-causes/basics-of-climate-change/

2. https://www.bettermeetsreality.com/the-challenges-with-chinas-transition-from-coal-to-natural-gas-renewable-energy/

3. https://en.wikipedia.org/wiki/Climate_change_feedback

4. https://www.science.org.au/learning/general-audience/science-booklets-0/science-climate-change/1-what-climate-change

5. https://www.bettermeetsreality.com/the-evidence-linking-greenhouse-gas-emissions-from-human-activity-climate-change-global-warming-together/  

6. https://theconversation.com/global-warming-has-already-raised-the-risk-of-more-severe-droughts-in-cape-town-107625

7. https://www.carbonbrief.org/uncertainty-in-climate-science

8. http://www.probeinternational.org/RS_ClimateChange_SummaryofScience.pdf

9. https://www.skepticalscience.com/print.php?r=282 

10. https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/basics-of-climate-change/ 

11. http://www.ox.ac.uk/research/research-impact/how-be-certain-uncertainty-climate-and-weather-forecasts 

12. https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.2011.0161 

13. https://www.forbes.com/sites/rrapier/2018/11/29/indisputable-facts-on-climate-change/#27796bb43d05

14. https://www.climatechangeinaustralia.gov.au/en/climate-campus/modelling-and-projections/projecting-future-climate/uncertainty-and-confidence/

15. https://skepticalscience.com/how-exxon-overstates-uncertainty-climate-science.html

16. https://skepticalscience.com/climate-sensitivity-uncertainties-concern.html (uncertainty of climate sensitivity to doubling emissions from pre industrial levels)

17. https://skepticalscience.com/how-much-15C-budget-left.html (sensitivity of the climate to CO2 emissions)

18. https://e360.yale.edu/features/paris-conundrum-how-to-know-how-much-carbon-is-being-emitted  

19. https://blogs.ei.columbia.edu/2016/02/02/el-nino-and-global-warming-whats-the-connection/

64 Barriers To Immediately Addressing Climate Change & Global Warming (Mitigation & Adaptation)

Barriers To Immediately Addressing Climate Change & Global Warming (Mitigation & Adaptation)

To address climate change and the warming of Earth – the number one thing we need to do is reduce emissions of C02, and to a lesser extent, reduce methane, nitrous oxide and black carbon, as quickly as possible – ideally down to zero emissions.

There are other mitigation and adaptation solutions and strategies, but that is the main one.

The energy/power generation, transport (mainly light vehicles and planes) and agriculture, land and forestry are the main sectors and industries to focus on, and implement solutions and improvements in.

This transition and implementation of solutions though is taking longer than some people want, and does not look to be a smooth one.

In this guide, we outline 64 challenges, difficulties and issues stopping this transition to zero emissions from taking place immediately.

(*This is not a complete list – it’s some specific examples and general examples to be aware of)

 

Summary – Some Barriers To Immediately Addressing Climate Change & Reducing Greenhouse Gases

 

1. Different Countries Face Different Challenges In Reducing Emissions

  • For example, developed countries face different challenges to less developed countries
  • Countries with eco conscious governments face different challenges to less eco conscious governments
  • Countries in hot or dry climates and coastal or island locations face different challenges to cold, wet, or inland locations

 

  • The challenges are different for different countries. Different portfolios face different implementation challenges, and potential synergies and trade-offs with sustainable development when combatting climate change

– IPCC Summary For Policymakers, 6 October, 2018

 

  • The potential for climate-resilient development pathways differs between and within regions and nations, due to different development contexts and systemic vulnerabilities. Efforts along such pathways to date have been limited and enhanced efforts would involve strengthened and timely action from all countries and non-state actors

– IPCC Summary For Policymakers, 6 October, 2018

 

2. Different Countries Emit Different Amounts Of GHG’s, & Put Different Amounts Of Effort & Money Into Reducing Them

Separate to the challenges a country faces, some countries are putting more money, time and effort into reducing their emissions and into reaching equitable emission targets than others

A country with lower emissions may put more time and effort into reducing emissions relative to a larger emitter

 

3. It Can Be Difficult To Get All Countries To Co-Operate & Work Together

Strengthening the capacities for climate action of national and sub-national authorities, civil society, the private sector, indigenous peoples and local communities can support the implementation of ambitious actions implied by limiting global warming to 1.5°C. International cooperation can provide an enabling environment for this to be achieved in all countries and for all people, in the context of sustainable development. International cooperation is a critical enabler for developing countries and vulnerable regions

– IPCC Summary For Policymakers, 6 October, 2018

 

International cooperation is a critical enabler for developing countries and vulnerable regions to strengthen their action for the implementation of 1.5°C-consistent climate responses, including through enhancing access to finance and technology and enhancing domestic capacities, taking into account national and local circumstances and needs

– IPCC Summary For Policymakers, 6 October, 2018

 

4. Partnerships Can Be Complex

Partnerships involving non-state public and private actors, institutional investors, the banking system, civil society and scientific institutions would facilitate actions and responses consistent with limiting global warming to 1.5°C

– IPCC Summary For Policymakers, 6 October, 2018

 

5. There’s Sometimes Multiple Groups & Actors Involved In Solutions – Which Takes Organisation, Planning & Maintenance

Cooperation on strengthened accountable multilevel governance that includes non-state actors such as industry, civil society and scientific institutions, coordinated sectoral and cross-sectoral policies at various governance levels, gender-sensitive policies, finance including innovative financing and cooperation on technology development and transfer can ensure participation, transparency, capacity building, and learning among different players

– IPCC Summary For Policymakers, 6 October, 2018

 

Collective efforts at all levels, in ways that reflect different circumstances and capabilities, in the pursuit of limiting global warming to 1.5o C, taking into account equity as well as effectiveness, can facilitate strengthening the global response to climate change, achieving sustainable development and eradicating poverty

– IPCC Summary For Policymakers, 6 October, 2018

 

6. Some Countries & Populations Are Less Affected By Climate Change Than Others, So Have Less Incentive To Implement Changes Quickly

Rich countries and more advantaged, inland, urban and resource rich countries aren’t affected as much, and so there is theoretically not as much urgency for them to do anything anytime soon. Populations at disproportionately higher risk of adverse consequences of global warming of 1.5°C and beyond include disadvantaged and vulnerable populations, some indigenous peoples, and local communities dependent on agricultural or coastal livelihoods . Regions at disproportionately higher risk include Arctic ecosystems, dryland regions, small-island developing states, and least developed countries

– IPCC Summary For Policymakers, 6 October, 2018

 

7. In Addition To The Country Level, There Can Be Issues At Regional & Local Level Too

Economic, institutional and socio-cultural barriers on national, regional and local scales depending on circumstances, capabilities and availability of capital

Technical measures and practices enabling deep emissions reductions include various energy efficiency options. In pathways limiting global warming to 1.5°C with no or limited overshoot, the electricity share of energy demand in buildings would be about 55–75% in 2050 compared to 50–70% in 2050 for 2°C global warming. In the transport sector, the share of low-emission final energy would rise from less than 5% in 2020 to about 35–65% in 2050 compared to 25–45% for 2°C global warming. Economic, institutional and socio-cultural barriers may inhibit these urban and infrastructure system transitions, depending on national, regional and local circumstances, capabilities and the availability of capital

– IPCC Summary For Policymakers, 6 October, 2018

 

8. Global And Regional Land Use Transition Could Be Difficult

Transitions in global and regional land use are found in all pathways limiting global warming to 1.5°C with no or limited overshoot, but their scale depends on the pursued mitigation portfolio. Model pathways that limit global warming to 1.5°C with no or limited overshoot project the conversion of 0.5–8 million km2 of pasture and 0–5 million km2 of non-pasture agricultural land for food and feed crops into 1–7 million km2 for energy crops and a 1 million km2 reduction to 10 million km2 increase in forests by 2050 relative to 2010 (medium confidence).16 Land use transitions of similar magnitude can be observed in modelled 2°C pathways (medium confidence).

Such large transitions pose profound challenges for sustainable management of the various demands on land for human settlements, food, livestock feed, fibre, bioenergy, carbon storage, biodiversity and other ecosystem services (high confidence). Mitigation options limiting the demand for land include sustainable intensification of land use practices, ecosystem restoration and changes towards less resource-intensive diets (high confidence). The implementation of land-based mitigation options would require overcoming socio-economic, institutional, technological, financing and environmental barriers that differ across regions

– IPCC Summary For Policymakers, 6 October, 2018

 

9. The Modelled Pathways To Achieve Certain Maximum Temperature Targets Such As 1.5 Degrees Warming Or Even 2 Degrees, Are Probably Very Unrealistic In Terms Of How Much Emissions Have To Reduce In The Time Spans Given

To reach 1.5 degrees celcius, model pathways suggest we need to meet a CO2 emissions decline of about 45% from 2010 levels by 2030 (40–60% interquartile range), reaching net zero around 2050 (2045–2055 interquartile range).

For limiting global warming to below 2°C11 CO2 emissions are projected to decline by about 20% by 2030 in most pathways (10–30% interquartile range) and reach net zero around 2075 (2065–2080 interquartile range).

– IPCC Summary For Policymakers, 6 October, 2018

 

10. The Modelled Pathways To Achieve Certain Maximum Temperature Targets Such As 1.5 Degrees Warming Or Even 2 Degrees, Are Probably Very Unrealistic In Terms Of Renewable Energy Supply

In 1.5°C pathways with no or limited overshoot, renewables are projected to supply 70–85% (interquartile range) of electricity in 2050

– IPCC Summary For Policymakers, 6 October, 2018

 

11. The Modelled Pathways To Achieve Certain Maximum Temperature Targets Such As 1.5 Degrees Warming Or Even 2 Degrees, Are Probably Very Unrealistic In Terms Of Reduction Of Coal Use

In modelled 1.5°C pathways with limited or no overshoot, the use of CCS would allow the electricity generation share of gas to be approximately 8% (3–11% interquartile range) of global electricity in 2050, while the use of coal shows a steep reduction in all pathways and would be reduced to close to 0% (0–2%) of electricity (high confidence)

– IPCC Summary For Policymakers, 6 October, 2018

 

12. Scale Is A Problem For The Changes That Climate Change Solutions Require

Pathways limiting global warming to 1.5°C with no or limited overshoot would require rapid and far-reaching transitions in energy, land, urban and infrastructure (including transport and buildings), and industrial systems (high confidence).

These systems transitions are unprecedented in terms of scale, but not necessarily in terms of speed, and imply deep emissions reductions in all sectors, a wide portfolio of mitigation options and a significant upscaling of investments in those options. The rates of system changes associated with limiting global warming to 1.5°C with no or limited overshoot have occurred in the past within specific sectors, technologies and spatial contexts, but there is no documented historic precedent for their scale

– IPCC Summary For Policymakers, 6 October, 2018

 

CO2 emissions from industry in pathways limiting global warming to 1.5°C with no or limited overshoot are projected to be about 75–90% (interquartile range) lower in 2050 relative to 2010, as compared to 50–80% for global warming of 2oC (medium confidence). Such reductions can be achieved through combinations of new and existing technologies and practices, including electrification, hydrogen, sustainable bio-based feedstocks, product substitution, and carbon capture, utilization and storage (CCUS).

These options are technically proven at various scales but their large-scale deployment may be limited by economic, financial, human capacity and institutional constraints in specific contexts, and specific characteristics of large-scale industrial installations. In industry, emissions reductions by energy and process efficiency by themselves are insufficient for limiting warming to 1.5°C with no or limited overshoot (high confidence).

– IPCC Summary For Policymakers, 6 October, 2018

 

13. Urban and Infrastructure Changes May Be Too Extensive

The urban and infrastructure system transition consistent with limiting global warming to 1.5°C with no or limited overshoot would imply, for example, changes in land and urban planning practices, as well as deeper emissions reductions in transport and buildings compared to pathways that limit global warming below 2°C

– IPCC Summary For Policymakers, 6 October, 2018

 

14. Mitigation Investments In Energy May Seem Expensive

Total annual average energy-related mitigation investment for the period 2015 to 2050 in pathways limiting warming to 1.5°C is estimated to be around 900 billion USD2015 (range of 180 billion to 1800 billion USD2015 across six models17). This corresponds to total annual average energy supply investments of 1600 to 3800 billion USD2015 and total annual average energy demand investments of 700 to 1000 billion USD2015 for the period 2015 to 2050, and an increase in total energy-related investments of about 12% (range of 3% to 23%) in 1.5°C pathways relative to 2°C pathways. Average annual investment in low-carbon energy technologies and energy efficiency are upscaled by roughly a factor of five (range of factor of 4 to 5) by 2050 compared to 2015

– IPCC Summary For Policymakers, 6 October, 2018

 

Global model pathways limiting global warming to 1.5°C are projected to involve the annual average investment needs in the energy system of around 2.4 trillion USD2010 between 2016 and 2035 representing about 2.5% of the world GDP

– IPCC Summary For Policymakers, 6 October, 2018

 

15. Investment, Financing, Access To & Mobilisation Of Funds For Climate Change Mitigation & Adaptation In General Has It’s Challenges

Directing finance towards investment in infrastructure for mitigation and adaptation could provide additional resources. This could involve the mobilization of private funds by institutional investors, asset managers and development or investment banks, as well as the provision of public funds. Government policies that lower the risk of low-emission and adaptation investments can facilitate the mobilization of private funds and enhance the effectiveness of other public policies. Studies indicate a number of challenges including access to finance and mobilisation of funds

– IPCC Summary For Policymakers, 6 October, 2018

 

16. Increasing Investment In Physical & Social Infrastructure Can Seem Undesirable For Some

Increasing investment in physical and social infrastructure is a key enabling condition to enhance the resilience and the adaptive capacities of societies to climate change

– IPCC Summary For Policymakers, 6 October, 2018

 

17. There Are Limitations For Some Renewable Energy Technologies In Some Countries

It’s acknowledged there are challenges, and differences between the options and national circumstances, political, economic, social and technical feasibility of solar energy.

But, wind energy and electricity storage technologies have substantially improved over the past few years. These improvements signal a potential system transition in electricity generation

– IPCC Summary For Policymakers, 6 October, 2018

 

18. Paris Agreement Mitigation Tactics For 1.5 Degrees Warming May Not Be Enough

Estimates of the global emissions outcome of current nationally stated mitigation ambitions as submitted under the Paris Agreement would lead to global greenhouse gas emissions18 in 2030 of 52–58 GtCO2eq yr-1 (medium confidence). Pathways reflecting these ambitions would not limit global warming to 1.5°C, even if supplemented by very challenging increases in the scale and ambition of emissions reductions after 2030 (high confidence). Avoiding overshoot and reliance on future large-scale deployment of carbon dioxide removal (CDR) can only be achieved if global CO2 emissions start to decline well before 2030

– IPCC Summary For Policymakers, 6 October, 2018

 

19. Awareness Of The General Public

Making the general public aware climate change and global warming, and how serious it is to be taken

 

20. Education Of The General Public

Following awareness comes education – on the challenges and solutions within these main issues, and the impacts/effects.

 

Education, information, and community approaches, including those that are informed by Indigenous knowledge and local knowledge, can accelerate the wide scale behaviour changes consistent with adapting to and limiting global warming to 1.5°C. These approaches are more effective when combined with other policies and tailored to the motivations, capabilities, and resources of specific actors and contexts (high confidence). Public acceptability can enable or inhibit the implementation of policies and measures to limit global warming to 1.5°C and to adapt to the consequences. Public acceptability depends on the individual’s evaluation of expected policy consequences, the perceived fairness of the distribution of these consequences, and perceived fairness of decision procedures

– IPCC Summary For Policymakers, 6 October, 2018

 

21. Cultural Change, & Behavioral Change Of The General Public

Following awareness and education comes making cultural and behavioral changes as part of everyday life

These are the beliefs, thoughts and actions of people and businesses

 

22. The Costs To Address Climate Change Mitigation And Adaptation Are Still Estimations

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.

– Ourworldindata.org

 

Adaptation finance consistent with global warming of 1.5°C is difficult to quantify and compare with 2°C. Knowledge gaps include insufficient data to calculate specific climate resilience-enhancing investments, from the provision of currently underinvested basic infrastructure. Estimates of the costs of adaptation might be lower at global warming of 1.5°C than for 2°C. Adaptation needs have typically been supported by public sector sources such as national and subnational government budgets, and in developing countries together with support from development assistance, multilateral development banks, and UNFCCC channels (medium confidence). More recently there is a growing understanding of the scale and increase in NGO and private funding in some regions (medium confidence). Barriers include the scale of adaptation financing, limited capacity and access to adaptation finance

– IPCC Summary For Policymakers, 6 October, 2018

 

23. Total Costs Of Climate Change Mitigation And Adaptation vs Costs To Address After Effects Of Climate Change Still Unclear

A lot of the costs and investments to mitigate and adapt to climate change vs the costs of the after effects of climate change are estimates and unclear to some decision makers.

 

24. Some Decision Makers May Not Be Aware Of The Potential Effects & Costs Of Delaying Action To Reduce Emissions

The challenges from delayed actions to reduce greenhouse gas emissions include the risk of cost escalation, lock-in in carbon-emitting infrastructure, stranded assets, and reduced flexibility in future response options in the medium to long-term (high confidence). These may increase uneven distributional impacts between countries at different stages of development

– IPCC Summary For Policymakers, 6 October, 2018

 

25. Some May Think That Sustainable Development Is A Hard Balancing Act vs Regular Development

Climate change impacts and responses are closely linked to sustainable development which balances social well-being, economic prosperity and environmental protection

– IPCC Summary For Policymakers, 6 October, 2018

 

26. Decision Makers Might Not Know That Sustainable Development Can Be Easier In Some Ways

Pathways that are consistent with sustainable development show fewer mitigation and adaptation challenges and are associated with lower mitigation costs.

– IPCC Summary For Policymakers, 6 October, 2018

 

27. Mitigation & Adaptation To & Of Climate Change Involves A lot Of Enabling Conditions

Mitigation and adaptation consistent with limiting global warming to 1.5°C are underpinned by enabling conditions, assessed in SR1.5 across the geophysical, environmental-ecological, technological, economic, socio-cultural and institutional dimensions of feasibility. Strengthened multi-level governance, institutional capacity, policy instruments, technological innovation and transfer and mobilization of finance, and changes in human behaviour and lifestyles are enabling conditions that enhance the feasibility of mitigation and adaptation options for 1.5°C consistent systems transitions.

– IPCC Summary For Policymakers, 6 October, 2018

 

28. There Can Be Trade Offs To Addressing Climate Change, Even If There’s Benefits – & The Net Effect Must Be Considered

Adaptation options specific to national contexts, if carefully selected together with enabling conditions, will have benefits for sustainable development and poverty reduction with global warming of 1.5°C, although trade-offs are possible

– IPCC Summary For Policymakers, 6 October, 2018

 

Adaptation to 1.5°C global warming can also result in trade–offs or maladaptations with adverse impacts for sustainable development. For example, if poorly designed or implemented, adaptation projects in a range of sectors can increase greenhouse gas emissions and water use, increase gender and social inequality, undermine health conditions, and encroach on natural ecosystems (high confidence). These trade-offs can be reduced by adaptations that include attention to poverty and sustainable development (high confidence).

– IPCC Summary For Policymakers, 6 October, 2018

 

Trade-offs between mitigation and adaptation, when limiting global warming to 1.5°C, such as when bioenergy crops, reforestation or afforestation encroach on land needed for agricultural adaptation, can undermine food security, livelihoods, ecosystem functions and services and other aspects of sustainable development. (high confidence)

– IPCC Summary For Policymakers, 6 October, 2018

 

Mitigation options consistent with 1.5°C pathways are associated with multiple synergies and trade-offs across the Sustainable Development Goals (SDGs). While the total number of possible synergies exceeds the number of trade-offs, their net effect will depend on the pace and magnitude of changes, the composition of the mitigation portfolio and the management of the transition. (high confidence)

– IPCC Summary For Policymakers, 6 October, 2018

 

29. In Addition To Trade Offs, It Can Be Difficult To Fully Consider People’s Needs, Biodiversity, and Other Sustainable Development Dimensions

1.5°C and 2°C modelled pathways often rely on the deployment of large-scale land-related measures like afforestation and bioenergy supply, which, if poorly managed, can compete with food production and hence raise food security concerns (high confidence).

The impacts of carbon dioxide removal (CDR) options on SDGs depend on the type of options and the scale of deployment (high confidence). If poorly implemented, CDR options such as BECCS and AFOLU options would lead to trade-offs. Context-relevant design and implementation requires considering people’s needs, biodiversity, and other sustainable development dimensions

– IPCC Summary For Policymakers, 6 October, 2018

 

30. Inter-lapping Between Decision Makers At Different Levels Can Get Tricky

A mix of adaptation and mitigation options to limit global warming to 1.5°C, implemented in a participatory and integrated manner, can enable rapid, systemic transitions in urban and rural areas (high confidence). These are most effective when aligned with economic and sustainable development, and when local and regional governments and decision makers are supported by national governments (medium confidence)

– IPCC Summary For Policymakers, 6 October, 2018

 

31. Sustainable Development Can Sometimes Present Risks

Mitigation consistent with 1.5°C pathways creates risks for sustainable development in regions with high dependency on fossil fuels for revenue and employment generation (high confidence). Policies that promote diversification of the economy and the energy sector can address the associated challenges (high confidence)

– IPCC Summary For Policymakers, 6 October, 2018

 

32. Good Government Policies That Are Kept Updated Are Needed In Most Countries At Most Levels

Redistributive policies across sectors and populations that shield the poor and vulnerable can resolve trade-offs for a range of SDGs, particularly hunger, poverty and energy access. Investment needs for such complementary policies are only a small fraction of the overall mitigation investments in 1.5°C pathways. (high confidence)

– IPCC Summary For Policymakers, 6 October, 2018

 

Policy tools can help mobilise incremental resources, including through shifting global investments and savings and through market and non-market based instruments as well as accompanying measures to secure the equity of the transition, acknowledging the challenges related with implementation including those of energy costs, depreciation of assets and impacts on international competition, and utilizing the opportunities to maximize co-benefits

– IPCC Summary For Policymakers, 6 October, 2018

 

The systems transitions consistent with adapting to and limiting global warming to 1.5°C include the widespread adoption of new and possibly disruptive technologies and practices and enhanced climate-driven innovation. These imply enhanced technological innovation capabilities, including in industry and finance. Both national innovation policies and international cooperation can contribute to the development, commercialization and widespread adoption of mitigation and adaptation technologies. Innovation policies may be more effective when they combine public support for research and development with policy mixes that provide incentives for technology diffusion.

– IPCC Summary For Policymakers, 6 October, 2018

 

33. System Transitions Can Require In Depth Planning

Limiting the risks from global warming of 1.5°C in the context of sustainable development and poverty eradication implies system transitions that can be enabled by an increase of adaptation and mitigation investments, policy instruments, the acceleration of technological innovation and behaviour changes

– IPCC Summary For Policymakers, 6 October, 2018

 

34. Discounted Marginal Abatement Costs Can Be An Issue

Modelled pathways limiting global warming to 1.5°C with no or limited overshoot project a wide range of global average discounted marginal abatement costs over the 21st century. They are roughly 3-4 times higher than in pathways limiting global warming to below 2°C (high confidence). The economic literature distinguishes marginal abatement costs from total mitigation costs in the economy.

– IPCC Summary For Policymakers, 6 October, 2018

 

35. CDR (Carbon Dioxide Removal) Use And Deployment Is Subject To Multiple Feasibility And Sustainability Constraints

All pathways that limit global warming to 1.5°C with limited or no overshoot project the use of carbon dioxide removal (CDR) on the order of 100–1000 GtCO2 over the 21st century. CDR would be used to compensate for residual emissions and, in most cases, achieve net negative emissions to return global warming to 1.5°C following a peak (high confidence)…..

CDR (carbon dioxide removal) deployment of several hundreds of GtCO2 is subject to multiple feasibility and sustainability constraints (high confidence). Existing and potential CDR measures include afforestation and reforestation, land restoration and soil carbon sequestration, BECCS, direct air carbon capture and storage (DACCS), enhanced weathering and ocean alkalinization

– IPCC Summary For Policymakers, 6 October, 2018

 

36. There Can Be Implementation Challenges With CDR

Reversing warming after an overshoot of 0.2°C or larger during this century would require upscaling and deployment of CDR at rates and volumes that might not be achievable given considerable implementation challenges

– IPCC Summary For Policymakers, 6 October, 2018

 

37. There May Be Limitations On The Speed, Scale, And Societal Acceptability Of CDR Deployment

CDR can determine the ability to return global warming to below 1.5°C following an overshoot. Carbon cycle and climate system understanding is still limited about the effectiveness of net negative emissions to reduce temperatures after they peak

– IPCC Summary For Policymakers, 6 October, 2018

 

38. Potential Negative Impact Of CDR

Most current and potential CDR measures could have significant impacts on land, energy, water, or nutrients if deployed at large scale (high confidence). Afforestation and bioenergy may compete with other land uses and may have significant impacts on agricultural and food systems, biodiversity and other ecosystem functions and services (high confidence). Effective governance is needed to limit such trade-offs and ensure permanence of carbon removal in terrestrial, geological and ocean reservoirs (high confidence). Feasibility and sustainability of CDR use could be enhanced by a portfolio of options deployed at substantial, but lesser scales, rather than a single option at very large scale

– IPCC Summary For Policymakers, 6 October, 2018

 

39. China & The US Are The Main C02 Emitters In The World*

*As of 2016.

China and The US as of 2017 made up roughly 45% of the world’s total C02 emissions.

This is not a barrier on it’s own. But, it does lead us to the next two points…

– chinapower.csis.org

 

40. The US Has Withdrawn From The Paris Agreement

With the US being a major C02 emitter, pulling out of the Paris Agreement, which was a major internationally binding agreement to meet warming targets – this is not desirable to limit and reduce emissions

 

41. China Is Heavily Reliant On Coal

Coal is heavily reliant on coal for so much of it’s economy, employment, energy needs and more.

A lot of employment, a lot of incomes, a lot of GDP growth is relying on the coal industry.

– thediplomat.com

 

42. China’s Installed Capacity Of Coal Is Not Expected To Peak Before 2025

Clashes with modeled pathways to stay below 1.5 degrees, and probably 2 degrees as well

– thediplomat.com

 

43. The Current Power System In China Is Still Influenced By The Last 15 Years’ Development Strategies

Development strategies have still mainly been around coal, not gas, or renewables

– thediplomat.com

 

44. There Is An Over Capacity Of Coal Power Plants In China

Which are essentially stranded investments that are either wasted money, or need to be used

– thediplomat.com

 

45. There Is Money & Profit To Be Made From Coal In China

The profit margin of coal-fire power in China increased in the last years, due to low prices of coal and to a relatively stable grid purchasing price – this is a market force which helps coal. There is money to be made out of coal right now still and into the near future

There are reports that China’s business and political elites are making billions from coal – essentially top level decision makers and influencers

– thediplomat.com

 

46. There Is Subsidisation And Protectionism Of Coal In China

Which makes coal energy prices in China are probably lower than they should be

– thediplomat.com

 

47. Industries In China Are Heavily Reliant On Coal

This is because of the current infrastructure set up. This makes it hard to transition to another energy source

– thediplomat.com

 

48. Relaxation On Regulations To Prevent New Investments In Dirty Energy Has Increased In China

This is due to decentralisation of environmental impact assessments of new power plants

– thediplomat.com

 

49. Pollution And Emission Fines Probably Aren’t High Enough In China

It has been cheaper in many cases to pay extra fees due to pollution or breaking environmental regulations than to implement energy-efficient solutions

– thediplomat.com

 

50. Technology For Renewables In China Not Quite Where It Should Be Yet To Compete With Coal On A Mass Scale

Technology impacts these renewable sources’ efficiency, operation and maintenance costs, and eventually, market prices.

– thediplomat.com

 

51. Infrastructure For Renewables In China Not Adequate Or Advanced Enough, Both Physically And Technologically

Infrastructure to take on new equipment is a main problem.  Electricity dispatching and absorption for example is an issue because current infrastructure for power transactions doesn’t take into account the variable nature of large scale power generation from wind and solar. Xinjiang, for instance, lost 38 percent of the energy produced by wind power in 2016. Nationally, 17 percent of all wind-power generation was curtailed in 2016 and has been increasing since 2014. Moreover, China’s energy transmission lines still do not support the transference of electricity without losing a considerable amount of energy, whereas industries rely on coal, rather than electricity, to maintain their daily operation.

Renewable power can be lost, wasted or not enter the grid

– thediplomat.com

 

52. Technology For Coal Production Can Be Improved In China

More technological improvements are urged for cleaner coal production

– thediplomat.com

 

53. Cost Of Clean Energy Compared To Coal In China

Renewable energy is still expensive compared to coal – but that is changing quickly

– thediplomat.com

 

54. Renewable Energy Can Reduce Disposable Income For The Consumer In China

If renewable energy costs more for consumers, it reduces their disposable income. Any price reform for new energy sources would reduce disposable income.

– thediplomat.com

 

55. Moving Away From Coal Can Mean Loss Of Jobs/Unemployment In The Short Term In China

Closing down existing coal power plants contributes high unemployment through loss of jobs of those who work there

– thediplomat.com

 

56. Moving Away From Coal Can Mean Loss Of Quality Of Life In The Short Term In China

Deteriorating life quality through short term loss of ability to heat homes in winter.

– thediplomat.com

 

57. Governments Can Lose Taxes In China With Decreased Coal Use

Governments lose revenue from industrial taxes from decreased use of coal power plants.

– thediplomat.com

 

58. Workers And Citizens Haven’t Been Trained In Renewable Energy From An Employment Perspective

There’s an education gap that does not prepare the workforce with skills required in a green economy – has negative effects.

– thediplomat.com

 

59. Geographical Suitability And Interrelationships Among Environmental Issues In China

Renewable energies depend on good geographical positioning, where the potential to generate energy outpaces the costs for installation and operation.

In China, this translated into a concentration of power plants in specific areas — wind and solar power, for instance, are more advantageous in grasslands and deserts, respectively — that already suffer from soil degradation, erosion, and water scarcity, such as Xinjiang and Inner Mongolia.

This leads to the second repercussion with respect to the interrelationships between environmental problems. Even though renewable energies have reversible impacts on the environment, their scale of production and installation in a concentrated area aggravates the above-mentioned problems.

Consequently, because renewable sources of energy depend on bigger and bigger areas of already degraded lands to scale its production, there is a physical hazard to China’s green transition.

– thediplomat.com

 

60. Some In China Don’t Have Confidence In Solar As A Viable Energy Source Alternative To Coal

Some say the coal culture will be a challenge to change, and some top decision-makers down do not regard solar as a viable alternative yet

– thediplomat.com

 

61. In Provincial China, Coal Might Be A Preference Over New Energy Sources

This can be due to a number of reasons and factors

 

62. The Biggest Power Users, Cities, And Industries/Businesses Need Clean Energy Within Close Geographic Distance In China

Many of the massive showcase renewable projects in the outer provinces are too far away from the energy-hungry cities and industrial centres of the east, and transmission lines and the grid haven’t been upgraded to utilise the power

– thediplomat.com

 

63. There Have Been Issues In The Transition From Coal To Cleaner Gas Fuel For Energy In China

  • Some coal fired boiler to gas conversion programs have been put off until 2020 – when additional gas import capacity from Russia will be ready
  • A large-scale transition needs adequate gas distribution capacity
  • Households plus a number of industrial businesses will need to switch from coal to gas for heating and electricity
  • If Beijing doesn’t take care to increase the supply of coal and put a lid on fast-rising prices – there will be more shortages
  • Hebei (where coal use was at 86.6 percent in 2015, versus a national average of 63 percent) has its problems with insufficient gas distribution infrastructure
  • Lack of communication between the government and the industry in the transition can also be an issue

– oilprice.com

 

64. With Electric Cars, Not Everything Is Green Yet

  • China’s electricity grid runs mainly on coal – this is an issue for electric vehicles
  • When accounting for emissions from electrical consumption, Greenpeace notes that both electric cars and traditional cars in China have similar “CO2 emissions and PM2.5 levels per kilometer driven.”
  • Furthermore, the lithium-ion batteries used to power EVs require enormous amounts of energy to produce, up to twice as much as is needed for manufacturing a standard combustion vehicle.

– chinapower.csis.org

 

Summary

There’s so many potential barriers that fit into different categories across different sectors and parts of society.

They might be related to politics, governance, policies and schemes, supplier side market forces, consumer side market forces, social awareness and behavior change, technology, the overall economy and so much more.

Addressing climate change through mitigation and adaptation requires a multi direction approach across all countries, and across all levels from national – down to local.

Reducing emissions of C02 in the energy sector, transport sector and agriculture, forestry and land use sectors are main places to start.

 

Sources

1. http://report.ipcc.ch/sr15/pdf/sr15_spm_final.pdf (IPCC Summary For Policymakers, 6 October, 2018)

2. Hannah Ritchie and Max Roser (2018) – “CO₂ and other Greenhouse Gas Emissions”. Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/co2-and-other-greenhouse-gas-emissions’ [Online Resource]

3. https://www.bettermeetsreality.com/the-challenges-with-chinas-transition-from-coal-to-natural-gas-renewable-energy/

4. https://chinapower.csis.org/china-greenhouse-gas-emissions/

5. https://thediplomat.com/2018/04/the-stumbling-blocks-to-chinas-green-transition/

6. https://oilprice.com/Latest-Energy-News/World-News/Chinas-Coal-To-Gas-Transition-Sputters.html

Latest Climate Change/Global Warming UPDATE (October 2018)

Latest Climate Change/Global Warming UPDATE (October 2018)

On the 6 October 2018, the ‘Summary For Policy Makers’ IPCC Special Report was issued.

This report was essentially a snapshot of where we are at and where we are going with climate change

The report was split into these sections

  • Understanding 1.5 Degrees Celcius Warming
  • Potential Impacts and Associated Risks of 1.5 Degrees Celcius Warming, Compared To 2 Degrees Celcius
  • Emission Pathways and System Transitions that are Consistent with 1.5°C Global Warming
  • Strengthening the Global Response in the Context of Sustainable Development and Efforts to Eradicate Poverty

What we’ve done is outlined the main points from this report to give you the latest Climate Change/Global Warming update.

 

Summary Of This Latest Climate Change Report

  • It’s looking extremely unlikely that warming is limited below 1.5 degrees
  • At the current rate, we will hit 1.5 degrees between 2030 and 2052
  • Limiting warming below 1.5 degrees would require global action to reduce C02 emissions and non C02 forcings (methane, black carbon and nitrous oxide) – the type of action which has never been seen before in human history
  • There are some significant differences between the risks and impacts on people, animals, the environment and earth overall when going from 1.5 degrees to 2 degrees warming
  • The groups of people that will see the initial and most significant impact from global warming, and an increase in maximum temperature are vulnerable and disadvantaged groups – less developed countries, regional, island, coastal, dry region, some indigenous and other populations
  • Although there are trade offs with the mitigations and adaptation to climate change, the total number of possible synergies exceeds trade off when considering energy demand, energy supply and land (although, their net effect will depend on the pace and magnitude of changes, the composition of the mitigation portfolio and the management of the transition)
  • Mitigating and adapting to climate change takes a global/international, national, and sub national effort and co-operation

As a side note to this report – it’s worth noting that some of the world’s more prominent cities have already reduced their emissions, and you can read this guide for more information on which cities they are and how they’ve done it.

 

Global Warming So Far

  • Human activities are estimated to have caused approximately 1.0°C of global warming above pre-industrial levels, with a likely range of 0.8°C to 1.2°C

 

When Will We Hit 1.5 Degrees Celcius Warming

  • Global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate (high confidence)

 

Carbon Budget Before Reaching 1.5 Degrees Celcius

  • By the end of 2017, anthropogenic CO2 emissions since the preindustrial period are estimated to have reduced the total carbon budget (amount of carbon we can release before we hit a certain temperature) for 1.5°C by approximately 2200 ± 320 GtCO2 (giga tonnes of C02)
  • The associated remaining budget is being depleted by current emissions of 42 ± 3 GtCO2 per year
  • The choice of the measure of global temperature affects the estimated remaining carbon budget.
  • Using global mean surface air temperature, as in AR5, gives an estimate of the remaining carbon budget of 580 GtCO2 for a 50% probability of limiting warming to 1.5°C, and 420 GtCO2 for a 66% probability

 

The Impact Of Emissions Already In The Atmosphere

  • Warming from anthropogenic emissions from the pre-industrial period to the present will persist for centuries to millennia and will continue to cause further long-term changes in the climate system, such as sea level rise, with associated impacts (high confidence), but these emissions alone are unlikely to cause global warming of 1.5°C (medium confidence)
  • Anthropogenic emissions (human emissions) are unlikely to cause further warming of more than 0.5°C over the next two to three decades (high confidence) or on a century time scale (medium confidence).

 

What Determines The Maximum Temperature Rise For Global Warming

  • Maximum temperature rise (and subsequently the probability of limiting warming to 1.5°C) is determined by 1) cumulative net CO2 emissions and 2) net non-CO2 radiative forcing due to methane, nitrous oxide, aerosols and other anthropogenic forcing agents

 

Current & Future Impacts Of Global Warming

  • Impacts on natural and human systems from global warming have already been observed (high confidence). Many land and ocean ecosystems and some of the services they provide have already changed due to global warming (high confidence)
  • Future climate-related risks depend on the rate, peak and duration of warming
  • Some impacts may be long-lasting or irreversible, such as the loss of some ecosystems (high confidence)

 

Adaptation To, & Mitigation Of Climate Change

  • Adaptation and mitigation are already occurring (high confidence). Future climate-related risks would be reduced by the upscaling and acceleration of far-reaching, multi-level and cross sectoral climate mitigation and by both incremental and transformational adaptation (high confidence)

 

Risks & Impacts For 1.5°C Warming, Compared To 2°C Warming

  • Climate-related risks for natural and human systems increase from the present, to 1.5 degrees celcius, to 2 degrees celcius
  • Climate models project robust differences in regional climate characteristics between present-day and global warming of 1.5°C, and between 1.5°C and 2°C.
  • These differences include increases in: mean temperature in most land and ocean regions (high confidence), hot extremes in most inhabited regions (high confidence), heavy precipitation in several regions (medium confidence), and the probability of drought and precipitation deficits in some regions (medium confidence)
  • By 2100, global mean sea level rise is projected to be around 0.1 metre lower with global warming of 1.5°C compared to 2°C (medium confidence). Sea level will continue to rise well beyond 2100 (high confidence), and the magnitude and rate of this rise depends on future emission pathways. A slower rate of sea level rise enables greater opportunities for adaptation in the human and ecological systems of small islands, low-lying coastal areas and deltas (medium confidence)
  • On land, impacts on biodiversity and ecosystems, including species loss and extinction, are projected to be lower at 1.5°C of global warming compared to 2°C. Limiting global warming to 1.5°C compared to 2°C is projected to lower the impacts on terrestrial, freshwater, and coastal ecosystems and to retain more of their services to humans (high confidence)
  • Limiting global warming to 1.5°C compared to 2ºC is projected to reduce increases in ocean temperature as well as associated increases in ocean acidity and decreases in ocean oxygen levels (high confidence). Consequently, limiting global warming to 1.5°C is projected to reduce risks to marine biodiversity, fisheries, and ecosystems, and their functions and services to humans, as illustrated by recent changes to Arctic sea ice and warm water coral reef ecosystems (high confidence)
  • Climate-related risks to health, livelihoods, food security, water supply, human security, and economic growth are projected to increase with global warming of 1.5°C and increase further with 2°C – mainly in disadvantaged, vulnerable, rural, coastal, small island and developing locations
  • With an increase from 1.5 to 2 degrees celcius – the reasons for concern increases for unique and threatened systems, extremem weather events, distribution of impacts, global aggregate impacts, and large scale singular events
  • With an increase from 1.5 to 2 degrees celcius – the impacts and risks increase for warm water corals, mangroves, small scale low latitude fisheries, the arctic region, terrestrial ecosystems, coastal flooding, fluvial flooding, crop yields, tourism and heat related morbidity and mortality

 

Adaptation For 1.5°C Warming, Compared To 2°C Warming

  • Most adaptation needs will be lower for global warming of 1.5°C compared to 2°C (high confidence)
  • A wide range of adaptation options are available to reduce the risks to natural and managed ecosystems (e.g., ecosystem-based adaptation, ecosystem restoration and avoided degradation and deforestation, biodiversity management, sustainable aquaculture, and local knowledge and indigenous knowledge), the risks of sea level rise (e.g., coastal defence and hardening), and the risks to health, livelihoods, food, water, and economic growth, especially in rural landscapes (e.g., efficient irrigation, social safety nets, disaster risk management, risk spreading and sharing, community-based adaptation) and urban areas (e.g., green infrastructure, sustainable land use and planning, and sustainable water management) (medium confidence)
  • Adaptation is expected to be more challenging for ecosystems, food and health systems at 2°C of global warming than for 1.5°C
  • Limits to adaptive capacity exist at 1.5°C of global warming, become more pronounced at higher levels of warming

 

Potential Pathways That Lead To 1.5°C Warming

  • In model pathways with no or limited overshoot of 1.5°C, global net anthropogenic CO2 emissions decline by about 45% from 2010 levels by 2030 (40–60% interquartile range), reaching net zero around 2050 (2045–2055 interquartile range).
  • For limiting global warming to below 2°C CO2 emissions are projected to decline by about 20% by 2030 in most pathways (10–30% interquartile range) and reach net zero around 2075 (2065–2080 interquartile range).
  • Non-CO2 emissions in pathways that limit global warming to 1.5°C show deep reductions that are similar to those in pathways limiting warming to 2°C. (high confidence)
  • So, Global total net CO2 emissions must reach net zero at around 2050, and Non-CO₂ emissions like methane, black carbon and nitrous oxide must also reduce, but don’t have to reach zero
  • There are 4 pathways outlined that can limit global warming to 1.5°C with no or limited overshoot
  • All pathways use Carbon Dioxide Removal (CDR), but the amount varies across pathways, as do the relative contributions of Bioenergy with Carbon Capture and Storage (BECCS) and removals in the Agriculture, Forestry and Other Land Use (AFOLU) sector.
  • We can get an idea of the characteristics of the four different pathways by reading the report analysis
  • Pathways limiting global warming to 1.5°C with no or limited overshoot would require rapid and far-reaching transitions in energy, land, urban and infrastructure (including transport and buildings), and industrial systems (high confidence). These systems transitions are unprecedented in terms of scale, but not necessarily in terms of speed, and imply deep emissions reductions in all sectors, a wide portfolio of mitigation options and a significant upscaling of investments in those options (medium confidence)
  • All pathways that limit global warming to 1.5°C with limited or no overshoot project the use of carbon dioxide removal (CDR) on the order of 100–1000 GtCO2 over the 21st century. CDR would be used to compensate for residual emissions and, in most cases, achieve net negative emissions to return global warming to 1.5°C following a peak (high confidence). CDR deployment of several hundreds of GtCO2 is subject to multiple feasibility and sustainability constraints (high confidence)

 

The Paris Agreement & Global Warming

  • Estimates of the global emissions outcome of current nationally stated mitigation ambitions as submitted under the Paris Agreement would lead to global greenhouse gas emissions in 2030 of 52–58 GtCO2eq yr-1 (medium confidence).
  • Pathways reflecting these ambitions would not limit global warming to 1.5°C, even if supplemented by very challenging increases in the scale and ambition of emissions reductions after 2030 (high confidence).
  • Avoiding overshoot and reliance on future large-scale deployment of carbon dioxide removal (CDR) can only be achieved if global CO2 emissions start to decline well before 2030 (high confidence)

 

The Impact Of Limiting Climate Change To 1.5°C On Sustainable Development, Eradication of Poverty & Reducing Inequalities

  • The avoided climate change impacts on sustainable development, eradication of poverty and reducing inequalities would be greater if global warming were limited to 1.5°C rather than 2°C, if mitigation and adaptation synergies are maximized while trade-offs are minimized (high confidence)
  • Adaptation options specific to national contexts, if carefully selected together with enabling conditions, will have benefits for sustainable development and poverty reduction with global warming of 1.5°C, although trade-offs are possible (high confidence)
  • Mitigation options consistent with 1.5°C pathways are associated with multiple synergies and trade-offs (involving energy demand, energy supply and land) across the Sustainable Development Goals (SDGs).
  • While the total number of possible synergies exceeds the number of trade-offs, their net effect will depend on the pace and magnitude of changes, the composition of the mitigation portfolio and the management of the transition. (high confidence)
  • Limiting the risks from global warming of 1.5°C in the context of sustainable development and poverty eradication implies system transitions that can be enabled by an increase of adaptation and mitigation investments, policy instruments, the acceleration of technological innovation and behaviour changes (high confidence)
  • For example, Global model pathways limiting global warming to 1.5°C are projected to involve the annual average investment needs in the energy system of around 2.4 trillion USD between 2016 and 2035 representing about 2.5% of the world GDP (medium confidence)
  • Sustainable development supports, and often enables, the fundamental societal and systems transitions and transformations that help limit global warming to 1.5°C. Such changes facilitate the pursuit of climate-resilient development pathways that achieve ambitious mitigation and adaptation in conjunction with poverty eradication and efforts to reduce inequalities (high confidence)

 

Factors That Can Help In Limiting Warming To 1.5°C

  • Strengthening the capacities for climate action of national and sub-national authorities, civil society, the private sector, indigenous peoples and local communities can support the implementation of ambitious actions implied by limiting global warming to 1.5°C (high confidence).
  • International cooperation can provide an enabling environment for this to be achieved in all countries and for all people, in the context of sustainable development. International cooperation is a critical enabler for developing countries and vulnerable regions (high confidence)

 

Sources

1. http://report.ipcc.ch/sr15/pdf/sr15_spm_final.pdf (‘Summary For Policy Makers’ IPCC Special Report)

Forecasts & Projections For Climate Change & Global Warming In The Future (up to 2100)

Forecasts & Projections For Climate Change & Global Warming For The Future (2030, 2050, 2100)

With climate change and global warming being talked about so much, it’s important to know what the future holds for warming and it’s associated effects on Earth.

We know the planet has warmed approximately 0.8 to 1.2 degrees celcius in the last century.

But, how much exactly is the climate expected to change, and how much is the earth expected to warm up into the future?

We’ve listed several forecasts and projections that outline where we can realistically expect to be heading by 2100 (the end of this century)

 

Climate Change & Global Warming Forecasts & Projections

Precise forecasts for greenhouse gas emissions, and particularly carbon dioxide emissions, are hard to make due to factors such as economic activity, price of fossil fuels, what happens in the electricity and transport industries, government policy developments, whether there are improvements in energy efficiency + more.

So, only estimated forecasts can be made which can be used as a general guide.

Several estimates include:

 

  • At the current rate, we will hit 1.5 degrees between 2030 and 2052
  • For limiting global warming to below 2°C CO2 emissions are projected to decline by about 20% by 2030 in most pathways (10–30% interquartile range) and reach net zero around 2075 (2065–2080 interquartile range).

– report.ipcc.ch

 

  • Current Policies – Current policies presently in place around the world are projected to reduce baseline emissions and result in about 3.4°C warming above pre-industrial levels.
  • Pledges – The unconditional pledges or promises that governments have made, including NDCs2 as of November 2017, would limit warming to about 3.16°C 3 above pre-industrial levels, or in probabilistic terms, likely limit warming below 3.5°C.
  • No Policies – In the absence of policies global warming is expected, to reach 4.1 °C – 4.8 °C above pre-industrial by the end of the century.
  • To Get To 1.5 Degrees Celcius – Limiting warming 1.5°C above pre-industrial by 2100 means that the emissions of greenhouse gases need to be reduced rapidly in the coming years and decades, and brought to zero around mid- century.

– climateactiontracker.org

 

  • If we have no climate policies implemented: this would result in an estimated 4.1-4.8°C warming by 2100 (relative to pre-industrial temperatures)
  • If we go forward with current climate policies: this would result in a projected warming of 3.1-3.7°C by 2100
  • If all countries achieve their current national 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”.
  • To achieve limiting average warming to 2°C: 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.
  • To achieve limiting average warming to 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.

– Ourworldindata.org

 

  • Taken together, all model projections indicate that Earth will continue to warm considerably more over the next few decades to centuries.
  • If there were no technological or policy changes to reduce emission trends from their current trajectory, then further warming of 2.6 to 4.8 °C (4.7 to 8.6 °F) in addition to that which has already occurred would be expected during the 21st century.
  • Projecting what those ranges will mean for the climate experienced at any particular location is a challenging scientific problem, but estimates are continuing to improve as regional and local-scale models advance.

– royalsociety.org

 

  • Stringent mitigation policies might be able to limit global warming (in 2100) to around 2 °C or below, relative to pre-industrial levels. Without mitigation, increased energy demand and extensive use of fossil fuels might lead to global warming of around 4 °C.
  • From the IPCC 4th Report – the best estimate for global mean temperature is an increase of 1.8 °C (3.2 °F) by the end of the 21st century. This projection is relative to global temperatures at the end of the 20th century. The “likely” range (greater than 66% probability, based on expert judgement) for the SRES B1 marker scenario is 1.1–2.9 °C (2.0–5.2 °F). For the highest emissions SRES marker scenario (A1FI), the best estimate for global mean temperature increase is 4.0 °C (7.2 °F), with a “likely” range of 2.4–6.4 °C (4.3–11.5 °F).
  • The range in temperature projections partly reflects (1) the choice of emissions scenario, and (2) the “climate sensitivity”.
  • Different scenarios make different assumptions of future social and economic development (e.g., economic growth, population level, energy policies), which in turn affects projections of greenhouse gas (GHG) emissions.
  • The projected magnitude of warming by 2100 is closely related to the level of cumulative emissions over the 21st century (i.e. total emissions between 2000–2100). The higher the cumulative emissions over this time period, the greater the level of warming is projected to occur.
  • Over the next several millennia, projections suggest that global warming could be irreversible. Even if emissions were drastically reduced, global temperatures would remain close to their highest level for at least 1,000 years

– wikipedia.org

 

  • 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.

– theconversation.com

 

  • Without new policies to mitigate climate change, projections suggest an increase in global mean temperature in 2100 of 3.7 to 4.8 °C, relative to pre-industrial levels (median values; the range is 2.5 to 7.8 °C including climate uncertainty).
  • The current trajectory of global greenhouse gas emissions is not consistent with limiting global warming to below 1.5 or 2 °C, relative to pre-industrial levels.
  • Pledges made as part of the Cancún Agreements are broadly consistent with cost-effective scenarios that give a “likely” chance (66-100% probability) of limiting global warming (in 2100) to below 3 °C, relative to pre-industrial levels

– Wikipedia.org

 

Sources

1. Hannah Ritchie and Max Roser (2018) – “CO₂ and other Greenhouse Gas Emissions”. Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/co2-and-other-greenhouse-gas-emissions’ [Online Resource]

2. https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/

3. https://climateactiontracker.org/countries/rating-system/

4. https://en.wikipedia.org/wiki/Effects_of_global_warming

5. https://theconversation.com/explainer-how-scientists-know-climate-change-is-happening-51421

6. https://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change

7. https://www.bettermeetsreality.com/latest-climate-change-global-warming-update-october-2018/

8. http://report.ipcc.ch/sr15/pdf/sr15_spm_final.pdf (‘Summary For Policy Makers’ IPCC Special Report)

What Are The Targets For Climate Change/Global Warming

What Are The Targets For Climate Change/Global Warming

In this short guide, we look at the global and country specific targets set to combat global warming and climate change.

 

How Much Has The World Warmed From Human Caused Climate Change Already

  • 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.

–  ourworldindata.org

 

  • multiple independent teams have concluded separately and unanimously that global average surface air temperature has risen by about 0.8 °C (1.4 °F) since 1900.

–  royalsociety.org

 

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

– climate.nasa.gov

 

Why Do We Need Targets For Global Warming Temperature Increase?

The residual greenhouse gases, and further greenhouse gas emissions both in the present and into the future will continue to warm the Earth from what we’ve seen in the last century.

This means climate change will have a greater and greater impact as the Earth gets warmer.

Targets for global warming temperature increase should hopefully minimise the impact climate change can have into the future.

 

What Are The Targets For Global Warming Temperature Increase?

Global Targets

There was a Paris climate conference (COP21) on December 2015, where 195 countries adopted the first-ever universal, legally binding global climate deal.

The Paris Agreement is a bridge between today’s policies and climate-neutrality before the end of the century.

It sets out a global action plan to put the world on track to avoid dangerous climate change by limiting global warming to well below 2°C.

In terms of targets, mitigation, and reducing emissions, governments agreed:

  • a long-term goal of keeping the increase in global average temperature to well below 2°C above pre-industrial levels;
  • to aim to limit the increase to 1.5°C, since this would significantly reduce risks and the impacts of climate change;
  • on the need for global emissions to peak as soon as possible, recognising that this will take longer for developing countries;
  • to undertake rapid reductions thereafter in accordance with the best available science.

– ec.europa.eu

 

It’s important to note that the U.S. President Donald Trump announced on 1 June, 2017, that the U.S. would withdraw from the Paris Agreement.

– sciencedirect.com

 

National Targets

Although we have total global emissions and the state of global warming over the world, there is also emissions and climate change on a national or regional level.

Each country contributes a different amount to the total global emissions (China and the United States contribute around 40 to 45% of total emissions for example), and face different challenges on a country wide level in terms of reducing emissions in the future.

Targets should ideally represent a ‘fair share’ contribution to reducing emissions (so higher emission countries should put in more effort to reduce).

 

  • With the adoption of the Paris Agreement, governments have agreed to hold warming well below 2°C, and pursue efforts to limit warming to 1.5°C above preindustrial levels.
  • But, they have also put forward their proposed contributions to a “fair sharing” of effort to move global emissions downward in the period 2020-2025-2030 in their (Intended) Nationally Determined Contributions.

– climateactiontracker.org

 

  • NDCs (Nationally Determined Contributions) embody efforts by each country to reduce national emissions and adapt to the impacts of climate change.
  • The Paris Agreement (Article 4, paragraph 2) requires each Party to prepare, communicate and maintain successive nationally determined contributions (NDCs) that it intends to achieve.
  • Parties shall pursue domestic mitigation measures, with the aim of achieving the objectives of such contributions.
  • It is understood that the peaking of emissions will take longer for developing country Parties, and that emission reductions are undertaken on the basis of equity, and in the context of sustainable development and efforts to eradicate poverty, which are critical development priorities for many developing countries.
  • Each climate plan reflects the country’s ambition for reducing emissions, taking into account its domestic circumstances and capabilities.

– unfccc.int

 

  • There are also Intended Nationally Determined Contributions (INDCs) by Least Developed Countries (LDCs)
  • LDCs have different national circumstances and levels of capacity, preparedness and ambition
  • a number of common challenges that LDCs face are:
    • their emissions are low in the global context, but they may wish to take actions to embrace low-carbon development and future-proof their investments;
    • they have a prevailing need for economic development and poverty reduction, including improving energy access;
    • they have limited capacity to undertake the analysis needed to develop their INDC;
    • they are likely to face constraints in implementing the actions envisaged in their INDCs and certain actions/levels of ambition are likely to be dependent or conditional on the provision of funding from developed countries;
    • they are among some of the most climate-vulnerable countries and therefore adaptation is likely to be a major focus of their national climate change plans.

– transparency-partnership.net

 

  • You can view Australia’s 2030 climate change target as an example at http://www.environment.gov.au/climate-change/publications/factsheet-australias-2030-climate-change-target
  • Australia’s target – Australia will reduce emissions to 26-28 per cent on 2005 levels by 2030.
  • This target represents a 50-52 per cent reduction in emissions per capita and a 64-65 per cent reduction in the emissions intensity of the economy between 2005 and 2030.

– environment.gov.au

 

  • You can also see how a country like Australia might measure and compare their emission target at https://www.climatecouncil.org.au/2015/08/09/a-simple-guide-to-australia-s-emissions-reduction-targets/
  • It involves knowing what your baseline year is, and knowing what current rate of emissions are, amongst other factors

– climatecouncil.org.au

 

  • There are sites like https://climateactiontracker.org that track different countries’ progress in meeting their fair share climate change targets.
  • As of 2018, they have countries categorised in the following categories (see at https://climateactiontracker.org/countries/):
  • Critically Insufficient Effort, & Efforts In Line With a 4+ Degree Celsius Temp. Rise – Russia, Saudi Arabia, Turkey, USA, Ukraine
  • Highly Insufficient Effort, & Efforts In Line With a 3 to 4 Degree Celsius Temp. Rise – Argentina, Canada, Chile, China, Indonesia, Japan, Singapore, South Africa, South Korea
  • Insufficient Effort, & Efforts In Line With a 2 to 3 Degree Celsius Temp. Rise – Australia, Brazil, EU, Kazakhstan, Mexico, New Zealand, Norway, Peru, Norway, UAE
  • Compatible Effort With Just Below A 2 Degree Celsius Temp. Rise – Bhutan, Costa Rica, Ethiopia, India, Phillipines
  • Compatible Effort With A 1.5 Degree Celsius Temp. Rise – Morocco, The Gambia
  • Role Model Effort, & Efforts Leading to A 1.5 Degree Celsius Temp. Rise Or Lower – No One Yet

– climateactiontracker.org

 

What Are The Projections & Forecasts For Where We Are Heading With Climate Change & Global Warming?

 

What Does Each Temperature Level Mean Exactly, & What’s The Difference Between Them?

 

Sources

1. Hannah Ritchie and Max Roser (2018) – “CO₂ and other Greenhouse Gas Emissions”. Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/co2-and-other-greenhouse-gas-emissions’ [Online Resource]

2. https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/

3. https://climate.nasa.gov/evidence/

4. https://www.bettermeetsreality.com/the-evidence-linking-greenhouse-gas-emissions-from-human-activity-climate-change-global-warming-together/

5. https://ec.europa.eu/clima/policies/international/negotiations/paris_en

6. https://climateactiontracker.org/countries/rating-system/

7. http://www.environment.gov.au/climate-change/publications/factsheet-australias-2030-climate-change-target

8. https://unfccc.int/process/the-paris-agreement/nationally-determined-contributions/ndc-registry

9. https://www.transparency-partnership.net/documents-tools/guide-indcs-intended-nationally-determined-contributions

10. https://en.wikipedia.org/wiki/Effects_of_global_warming

11. https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/basics-of-climate-change/

12. https://climateactiontracker.org/global/temperatures/

13. https://www.climatecouncil.org.au/2015/08/09/a-simple-guide-to-australia-s-emissions-reduction-targets/