What is Global Warming

Fossil fuels are composed mostly of carbon. When they are burned this carbon is released into the atmosphere, mainly in the form of carbon dioxide, CO2. We currently emit roughly 5 billion tones of carbon into the atmosphere each year. As a result, there has been a steady increase in global atmospheric levels of CO2. This increase in CO2 (along with other gases including methane, ozone, and CFCs) presents a problem, because these gases are "greenhouse" gases, that is they absorb infrared radiation (i.e., "heat") that is radiated out from the earth. Thus, heat that would otherwise be lost to space is trapped in the atmosphere, leading to increased temperatures. Climatologists have predicted that, as a result of increasing concentrations of greenhouse gases in the atmosphere, the earth's temperature will increase by about 3 degrees Celsius by the year 2030. This will result in significant changes in local climate, in some areas leading to loss of arable land, and an increase in sea level with associated coastal flooding. In addition, global warming may exacerbate the photochemical smog problem. Hundreds of atmospheric scientists are employed worldwide to study the magnitude and implications of this problem, and potential solutions.