The 5th Conference on Polar Meteorology and Oceanography

2.3
MOUNT PINATUBO AEROSOL OVER ANTARCTICA- AN OPPORTUNITY FOR VERIFICATION OF CLIMATE BACKCASTING

V K. Saxena, North Carolina State University, Raleigh, NC

The eruption of Mt. Pinatubo (15.14 N, 120.35 E) in the Philippines on 15 June 1991 injected massive amount of aerosol forming substances into the stratosphere. We have demonstrated (Atmospheric Environment 30, 1797-1804, 1996; J. Geophys. Res., 101, 19455-19463, 1996) that based on SAGE II (Stratospheric Aerosol and Gas Experiment) satellite measurements, the Antarctic aerosol was enhanced and showed a large particle mode superimposed on the small background particle mode. The net result was an order of magnitude increase in column number concentration, a 5-fold increase in column surface area, and greater than 20-fold increase in column mass loading during the austral summer of 1992. By March, 1994, the Antarctic atmosphere showed uniform background level aerosol concentration. Obviously, the Pinatubo aerosol had settled on the Antarctic ice sheet. This paper outlines an strategy for obtaining the shallow ice core samples during upcoming U.S. International Trans-Antarctic Scientific Expedition (ITASE). The latter will provide a unique and unusual opportunity to analyze atmospheric transfer functions and answer the following crucially important question: How well does the Antarctic ice sheet aerosol represent the prevailing atmospheric conditions on a regional/synoptic scale?

The 5th Conference on Polar Meteorology and Oceanography