That global warming has happened in the recent past is evident from the rise in the mean temperature of the earth’s atmosphere. Many ecosystems will be unable to adapt suitably to such rapid changes in climate and this will lead to extinction of some animal species. In addition to the impact on ecosystems, human agriculture, health and water resources are all being affected by global warming sparking wide spread apprehension across the globe.
Scientists agree that human activities have led to release of green house gases that in turn are responsible for global warming during the last century. This has been especially marked during the last 50 years. As humans began to use petroleum and burn coal and oil to heat their cities and run their machines, levels of carbon dioxide have risen by almost 30%. The concentration of nitrous oxide and methane that are by products of farming, coming from rice fields and cattle have also risen by 10 – 15 %. In 2002 about 40% of U.S. carbon dioxide emissions were a result of the burning of fossil fuels for the purpose of electricity generation. Coal accounted for 93 percent of the emissions from the electric utility industry. Statistics show that of the total energy consumption in the US every year, almost 85 % comes from gas and petroleum products and coal. (American Gas Association) About 33% of U.S carbon dioxide emissions come from the burning of gasoline in engines of cars and light trucks. Hence the second biggest sources of these green house gases are road vehicles and industries. Emissions from airplanes and buildings add their own percentages of Carbon Dioxide to the atmosphere and aid global warming. It has been found that water vapor in the atmosphere - a powerful greenhouse gas, has been increasing, due to warming caused by carbon dioxide, methane and other green house gases. Deforestation is yet another major cause of