Mc. Pitts et Lw. Thomason, THE IMPACT OF THE ERUPTIONS OF MOUNT-PINATUBO AND CERRO HUDSON ON ANTARCTIC AEROSOL LEVELS DURING THE 1991 AUSTRAL SPRING, Geophysical research letters, 20(22), 1993, pp. 2451-2454
At the beginning of the 1991 Austral spring, volcanic aerosols from Mt
. Pinatubo and Cerro Hudson were present in the polar stratosphere of
the Southern Hemisphere. Satellite observations of aerosol extinction
were used to identify and track the movement of these aerosols in the
vicinity of the Antarctic vortex during August through November 1991.
A layer of mature Mt. Pinatubo aerosols was identified near 21 km and
a layer of fresh Cerro Hudson aerosols was identified near 12 km. This
altitude separation of the Mt. Pinatubo and Cerro Hudson aerosols was
observed throughout the period. Below 15 km, the polar stratosphere w
as subject to episodes of strong wave activity which transported the C
erro Hudson aerosols poleward and, after the middle of September, they
became a persistent feature beneath the vortex. Above 15 km, signatur
es of Mt. Pinatubo aerosols were observed near the vortex boundary, bu
t significant portions of the vortex interior remained free of any det
ectable intrusions of Mt. Pinatubo aerosols until the final warming in
mid-November.