Pub. date: 2008 | Online Pub. Date: May 28, 2008 | DOI: 10.4135/9781412963930 | Print ISBN: 9781412941655 | Online ISBN: 9781412963930| Publisher:SAGE Publications, Inc.About this encyclopedia
One reason the earth is teeming with life is the existence of a natural greenhouse effect. The earth is heated by the sun. After the sun's rays strike the earth, many of them bounce back into space, and the planet would be much colder if there were not gases in the atmosphere to trap part of the heat from these reflected rays. Since the start of the industrial revolution, changing economic activities have been increasing the concentrations of heat-absorbing greenhouse gases (GHGs) in the atmosphere. Computer-generated climate models suggest that the buildup of these additional GHGs, particularly carbon dioxide (CO 2 ) from burning fossil fuels, will warm the earth's surface. The hypothesis that there will be rising global temperatures from increased human emissions of GHGs and that temperature increases will in turn melt global ice caps, raise sea levels, and increase extreme weather events like hurricanes and floods is ...