Curiously the most important gas for heat retention in the atmosphere is water vapor. Water vapor is however not a direct concern for global warming researchers as man does not directly influence the concentration of water vapor in the atmosphere and water vapor returns to the Earth very quickly after evaporation. The gases of concern are anthropogenically introduced and remain in the atmosphere for long periods of time allowing their concentrations to build up. Current information is maintained by the U.S. Department of Energy at the Carbon Dioxide Information Analysis Center , where David Keeling's original data can be viewed. In 1986, three british scientists published a landmark article in the journal Nature showing wide yearly fluctuations in stratospheric ozone over the Antarctic.
Statospheric ozone is responsible for most of the atmosphere's absorption of UV-B radiation.
UV-B radiation degrades DNA which can induce many forms of cancer. The major constituents of living organisms are made up of carbon, oxygen, hydrogen, nitrogen, phosphorous and sulfur. Oxygen is readily usable in its elemental form but carbon, nitrogen, phosphorous and sulfur must be fixed for biological utilisation. These substances cycle between living and non-living reservoirs and these cycles are referred to as biogeochemical cycles. Part of global change research is to identify the major reservoirs of each of these elements and determine the rates at which they are transported or converted between these reservoirs.