Characteristics of Antarctic stratospheric aerosols during the 1987 ozone depletion episode based on SAGE II satellite observations

An enhanced aerosol layer of relatively larger particles at altitudes between 21 and 23 km was found in Antarctic region. The effective radius can be fitted by Angstrom coefficient using either a linear or quadratic equation. On the average, in the region below 18 km, maximum values for the parameters of mass loading, total number, and surface area concentration were found to be located just above the region of the most severe ozone depletion. As to the columnar aerosol properties, bimodal feature in the size distribution is found during the days when the peak values of optical depth are greater than 10^-3. Relatively abundant population of smaller particles is associated with the region of severe ozone depletion. The distinct latitudinal gradients of these aerosol parameters suggest that the stratospheric aerosols are separated into two regimes near 62°S-63°S, probably as a result of the dynamics introduced by polar vortex. Smaller and larger particles dominate at higher and lower latitudes, respectively. -from Authors