Climate change is the greatest environmental challenge facing the world today. Rising global temperatures will bring changes in weather patterns, rising sea levels and increased frequency and intensity of extreme weather events. The effects will be felt here in the UK and internationally there may be severe problems for people in regions that are particularly vulnerable to change.

The Earth has warmed by 0.74°C over the last hundred years. Around 0.4°C of this warming has occurred since the 1970s. mean global temperatures are likely to rise between 1.1 and 6.4°C (with a best estimate of 1.8 to 4°C) above 1990 levels by the end of this century, depending on our emissions. This will result in a further rise in global sea levels of between 20 and 60cm by the end of this century, continued melting of ice caps, glaciers and sea ice, changes in rainfall patterns and intensification of tropical cyclones.

Average annual temperatures across the UK may rise by between 2°C and 3.5°C by the 2080s, with the amount of warming dependent on future levels of greenhouse gas emissions. High summer temperatures will become more frequent and very cold winters will become increasingly rare. For example, a very hot August, such as that experienced in 1995 may occur as often as two years in three by the 2080s. It is not just temperatures that will change in the UK, but also rainfall amounts and frequency. Winters will become wetter and summers may become drier across all of the UK. The largest relative changes will be in the south and east where summer rainfall may decline by up to 50% by the 2080s. Heavy winter rainfall will become more frequent, but the amount of snow could decline by 60% - 90% by the 2080s.

Sea levels will continue to rise and could be between 260 and 860 mm above the current level in southeast England by the 2080s.