Global warming

One of the most important problem facing the world is global warming and to be honest its the biggest risk problem in this century. Although scientists were warning the people and government about this problem since long time , No one responded with the warning.
The mening of Global warming is the gradual increase in global temperatures caused by the emission of gases that trap the sun's heat in the Earth's atmosphere. Gases that contribute to global warming include carbon dioxide, methane, nitrous oxides, chlorofluorocarbons (CFCs), and halocarbons (the replacements for CFCs). The carbon dioxide emissions are primarily caused by the use of fossil fuels for energy.
An increase in global temperatures can in turn cause other changes, including a flooding , an increase in the frequency and intensity of extreme weather events, reduction in agricultural yields due to changes in the amount and pattern of precipitation, increases in the ranges of disease vectors, reduced summer stream flows, further melting of glaciers, and species extinctions.