Over the past 200 years, emissions from cars, power plants, and other human activities have led to about a 30 percent increase in the natural concentration of carbon dioxide and more than a doubling of atmospheric concentration of methane. Globally, the average temperature of the Earth has warmed about 1 degree Farenheight since the mid-19th century when measurements began. There is strong scientific evidence that the continued addition of greenhouse gases into the atmosphere will continue to alter global climate and cause increasing temperatures as well as changes in rainfall and other weather patterns. The IPCC reports that unless the world takes steps to reduce the emissions of gases that are causing this greenhouse effect, global temperatures could rise 1.5 to 6 degrees Fahrenheit by the year 2100. This would represent the fastest rate of warming since the end of the last ice age more than 10,000 years ago.
Climate change poses significant risks to human health, the environment, and the economy.
Although there are many uncertainties about the timing, magnitude and regional patterns involved, there is strong evidence that these changes will have significant implications for humankind and the environment. A rise in sea level of 6-38 inches by the year 2100. Variations in regional climate and vegetation. Changes in productivity of agricultural lands. Increases in the intensity and severity of tropical storms.