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Climate change: Copenhagen in graphics Climate change: Copenhagen in graphics
(about 21 hours later)
The energy supply is the biggest source of emissions globallyThe energy supply is the biggest source of emissions globally
Where do greenhouse gas emissions come from?Where do greenhouse gas emissions come from?
Which countries are most responsible for causing human-induced climate change?Which countries are most responsible for causing human-induced climate change?
And have governments pledged tough enough cuts so far to keep the global average temperature rise within "safe limits"?And have governments pledged tough enough cuts so far to keep the global average temperature rise within "safe limits"?
As the UN summit in Copenhagen approaches, we look at the past, present and possible futures of climate change.As the UN summit in Copenhagen approaches, we look at the past, present and possible futures of climate change.
Growing populations and rising living standards helped drive emissions ever upwards during the second half of the 20th century. In the first years of the new century, China's emissions overtook those of the US.
Most aspects of modern life can require the burning of fossil fuels in some form, whether it is the daily commute, cooking a meal or heating a home. The energy supply is the greatest contributor to man-made global warming.
Carbon dioxide is the most significant greenhouse gas. Methane and nitrous oxide - produced in agriculture and industry - have a more powerful warming effect per molecule, but they have smaller concentrations in the atmosphere.
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Growing populations and rising living standards helped drive emissions ever upwards during the second half of the 20th century. In the first years of the new century, China's emissions overtook those of the US.
Most aspects of modern life can require the burning of fossil fuels in some form, whether it is the daily commute, cooking a meal or heating a home. The energy supply is the greatest contributor to man-made global warming.
Carbon dioxide is the most significant gas in the man-made greenhouse effect. Methane and nitrous oxide - from agriculture and industry - have a more powerful warming effect per molecule, but smaller concentrations in the atmosphere.
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Global emissions have risen steadily in recent decades.Global emissions have risen steadily in recent decades.

CLIMATE CHANGE GLOSSARY

Glossary in full

CLIMATE CHANGE GLOSSARY

Glossary in full
But when trying to assign "responsibility" for causing climate change, how should they be measured?But when trying to assign "responsibility" for causing climate change, how should they be measured?
Populous developing countries such as China and India have relatively high overall emissions - comparable with many developed countries.Populous developing countries such as China and India have relatively high overall emissions - comparable with many developed countries.
But each of their citizens produces a much smaller amount than counterparts in regions such as North America or Western Europe.But each of their citizens produces a much smaller amount than counterparts in regions such as North America or Western Europe.
Countries that industrialised early and grew rich early because of that industrialisation, such as the UK, Germany and the US, have a higher "historical footprint".Countries that industrialised early and grew rich early because of that industrialisation, such as the UK, Germany and the US, have a higher "historical footprint".
In some peoples' eyes, this gives them a higher responsibility for curbing the problem.In some peoples' eyes, this gives them a higher responsibility for curbing the problem.
A number of academic teams have calculated how emissions are likely to rise in the next few decades, and what that is likely to mean in terms of rising temperatures.A number of academic teams have calculated how emissions are likely to rise in the next few decades, and what that is likely to mean in terms of rising temperatures.
Copenhagen: Where they stand What's your Copenhagen solution?Copenhagen: Where they stand What's your Copenhagen solution?
Their projections are not exact because there are many sources of uncertainty in the calculations, including the exact relationship between greenhouse gas levels and temperature rise.Their projections are not exact because there are many sources of uncertainty in the calculations, including the exact relationship between greenhouse gas levels and temperature rise.
A number of developed countries and blocs have set targets for cutting their emissions, some of which depend on what other countries do.A number of developed countries and blocs have set targets for cutting their emissions, some of which depend on what other countries do.
The EU, for example, will cut emissions by 20% from 1990 levels - but if there is a global deal, that will rise to 30%.The EU, for example, will cut emissions by 20% from 1990 levels - but if there is a global deal, that will rise to 30%.
Some developing nations have also pledged to reduce the rate at which their emissions are growing.Some developing nations have also pledged to reduce the rate at which their emissions are growing.
If implemented, are these curbs enough to keep the global average temperature rise below 2C - the target adopted by G8, the EU and a number of major developing countries?If implemented, are these curbs enough to keep the global average temperature rise below 2C - the target adopted by G8, the EU and a number of major developing countries?
#ss-climate_change_pledges h2 {background:#FFFFFF; color:#333333; font:bold 0.85em verdana;}-->Climate Change Pledges 1990 - 2030-->
Analysts project that if no further action is taken on emissions, man-made warming will go beyond the relative safety of 2C above pre-industrial levels.
To hit the 2C target emissions in 2020 need to be 17Gt CO2e lower than they would be under a "business as usual" path - to 44Gt.
Current pledges could reduce emissions to 50-55Gt a year. This leaves a potential gap of between 6 and 11Gt in 2020.
If emissions hit 44Gt in 2020, pegging climate change to 2C is not certain. If emissions are higher, the chances of achieving this target are lower.
BACK{current} of {total}NEXT 		#ss-climate_change_pledges h2 {background:#FFFFFF; color:#333333; font:bold 0.85em verdana;}-->Climate Change Pledges 1990 - 2030-->
Analysts project that if no further action is taken on emissions, man-made warming will go beyond the relative safety of 2C above pre-industrial levels.
To hit the 2C target emissions in 2020 need to be 17Gt CO2e lower than they would be under a "business as usual" path - to 44Gt.
Current pledges could reduce emissions to 50-55Gt a year. This leaves a potential gap of between 6 and 11Gt in 2020.
If emissions hit 44Gt in 2020, pegging climate change to 2C is not certain. If emissions are higher, the chances of achieving this target are lower.
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According to the European Climate Foundation analysis - and others - commitments made so far are probably not enough to meet the G8 target.According to the European Climate Foundation analysis - and others - commitments made so far are probably not enough to meet the G8 target.
This shortfall is one of the issues likely to be highlighted during the Copenhagen conference.This shortfall is one of the issues likely to be highlighted during the Copenhagen conference.