Climate change means the unusual changes that are happening now and we expect to the world's weather in the coming years. The changes are happening in part because we are burning oil, gas and coal, which give off carbon dioxide into the air. Other polluting gases are adding to the effect of the carbon dioxide.
Carbon dioxide in the air acts like a greenhouse, keeping the sun's heat down here instead of radiating away into space. Gases that do this are called greenhouse gases. Other greenhouse gases include water vapour and methane. Burningoil, gas and coal also produces water vapour. Water vapour below the clouds is not a problem, because it becomes rain and falls to the ground, but water vapour produced high up by jet planes stays there. For this reason jet planes cause about five times as much climate change as the carbon alone would suggest.
Climate change is already happening, and could become catastrophic in the next few decades unless we stop burning oil, coal and gas, the fossil fuels. Under pressure from environment groups, the government recently passed the Climate Change Act, which commits the UK to reduce fossil fuel use by 80% by 2050. If governments can agree, there is likely to be great pressure worldwide to reduce the amount of these fossil fuels that we use in the next few years.
The latest official UK forecasts have been produced by the UK Climate Impacts Programme. They have published an explanation of the forecasts and the answers to frequently asked questions.