Lidar depolarization studies of the atmosphere at the South Pole

Some examples of lidar backscatter and depolarization profiles obtained at the South Pole during the austral summer period 1976-77 are presented. The examples illustrate the variety of data obtainable from various meteorological conditions as well as how this kind of lidar can help determine cloud layer structures in the polar atmosphere. Clear sky ice crystal precipitation and light ice precipitation under overcast sky conditions produced volume backscatter coefficients in the 2-4 x 10(-3)-km(-1) range and depolarization values up to 0.46, while mixed phase and supercooled water drop layers were also observed with maximum backscatter coefficients ranging from 5 x 10(-2) to 2.4 x 10(-1) km(-1) and depolarization values from a few to ~20%. Some of these layers may have contained aligned plates which resulted in enhanced backscatter values and lower depolarization values, therefore, the identification is sometimes ambiguous.