GLOBAL WARMING

Global warming is the increase in the average temperature of the Earth's near-surface air and oceans since the mid-20th century and its projected continuation. Global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) during the last century.

IMPACTS OF GLOBAL WARMING

Global warming will have serious impacts on the environment and on society. Higher temperatures will cause a melting of ice in Greenland and Antarctica. This will accelerate the rise of sea level. The speed at which global warming is expected to occur in the 21st century is faster than most plant and animal species will be able to cope with. Some will adapt but others will suffer and may become extinct.

Global warming will affect agriculture. New crops will be able to be grown in areas that are currently too cold to support them. However, more pests and diseases may offset any benefits higher temperatures may have. Water resources will also be affected. Some reservoirs may dry up if temperature increases, especially if rainfall also decreases. Rising sea levels may pollute fresh groundwater supplies with salt water.

Global warming will also affect human health. There may be more heat-related illnesses in hotter summers, and increased breathing problems as higher temperatures increase air pollution in cities, reducing air quality. The malaria mosquito may also be able to spread to other regions of the world where it is currently too cold to survive and breed.

More extreme weather, for example storms, floods and droughts will have severe impacts on the environment and on society. The poorest people in society will unfortunately be those least able to cope with the impacts of global warming.