The climate has changed continually throughout Earth's history because of natural causes. But today's climate change is different - it is caused by humans.
Find out how scientists first discovered that human activity was causing global warming, what consequences they think this will have over the next century, and what the international community is doing to limit the damage.
Without carbon dioxide in the atmosphere the Earth would be too cold for many species to live. But too much carbon dioxide is just as destructive. Find out more.
When did scientists first discover the greenhouse effect? What was the evidence? And when did scientists from across the world first report the problem? Find out here.
Earth's climate has always been changeable because of natural causes. Find out why today's climate change is different.
What were the successes and weaknesses of the Kyoto treaty on climate change? And what needs to be changed in future agreements?
Why do forests help to reduce global warming and how can we preserve them? Pavan Sukhdev, who worked with the United Nations Environment Programme, explains in the video.