Polar Seas - Role in Global Climate

Role in Global Climate

The polar seas play an important role in the global climate:

• Carbon export/carbon sequestration: Effects concentration of carbon dioxide in the Earth's atmosphere.
• Dimethylsulfoniopropionate (DMSP/DMS) production: DMSP/DMS serves as the nucleus in cloud formation and changes the regional albedo and precipitation.
• Earth's energy budget: clouds increase albedo, sea-ice increases albedo, ice shelves increase albedo etc.
• Formation of deep and bottom waters: the polar areas are the source of ocean deep and bottom cold waters. Due to the sinking of cold and dense saline waters near Greenland, and at the Antarctic Convergence, among other sites, the global ocean circulation is maintained.

Models predict a latitudinal effect in response to climate change. These would be expected to be first obvious in polar and subpolar regions. The decline of arctic ocean summer ice coverage was assumed to be one such sign, however, the reversal of that trend leaves the question open as the origins of the now reversed 30 year trend. In 1979, the cover of Time magazine was illustrated with an image of arctic ice covering and expanding BEYOND the arctic basin, opinion seems to have little value. Real data reveal the trend of ice coverage to be on the increase. If this increase will continue, only time will tell. Developed nations ceased the production and use of chlorofluorocarbons and the atmospheric abundance and consequent ozone depletion are generally on the decrease. ozone hole Breaking-off of polar ice shelves is a continuing process with increases in Western Antarctica balanced by decreases in Eastern Antarctica. Careful study has revealed that the volume of ice in Western Antarctica was incorrectly estimated and shows no significant change attributable to climate change over the observation period.