Antarctica and global change

Several areas of the Antarctic ecosystem are important harbingers of climate change. Antarctic sea ice responds to climate temperature change much more strongly than other areas and can affect the ocean transport of dissolved gases such as oxygen and carbon dioxide. Changes in the mass balance of the Antarctic ice sheet can have an influence on the rate of future sea-level change. This ice sheet also holds an extensive record of past global environmental changes that are revealed by studying deep ice cores. Changes in the stratospheric ozone concentration may be a forerunner of more widespread depletion in the future. Increased UV radiation due to O sub(3) depletion can destroy phytoplankton in the Antarctic sea ice zone and subsequently affect other components of the marine food chain. Changes in the sea ice and temperatures in the Antarctic region can alter Southern Hemisphere atmospheric circulation and ocean currents. These areas are discussed to illustrate the role that the Antarctic plays in global change. Current Antarctic research programs are highlighted.