Concentrations and size distributions of Antarctic stratospheric aerosols
Abstract
Particle Measuring Systems laser particle spectrometer (ASAS-X and FSSP) probes were used to measure aerosol particle concentrations and size distributions during 11 out of 12 ER-2 flights between Punta Arenas (53°S) and Antarctica (up to 72°S) from August 17 to September 22, 1987. The time resolution was 10 s, corresponding to a spatial resolution of 2 km. The data were divided into two size classes (0.05-0.25 and 0.53-5.5 μm radius) to separate the small particle from the coarse particle populations. Results show that the small particle concentrations are typical for a background aerosol during volcanic quiescence. This concentration is generally constant along a flight track; in only one instance did we measure a depletion of small particles during a polar stratospheric cloud (PSC) encounter, suggesting a nucleation of type I PSC particles on background aerosols. Temporary increases of the coarse particle concentrations indicated the presence of tenuous polar stratospheric clouds that were encountered most frequently at the southernmost portion of a flight track and when the aircraft descended to lower altitudes. During "particle events," particle modes were found at 0.6 μm radius, corresponding to type I PSCs, and occasionally, a second mode at 2.0 μm radius, corresponding to type II PSCs.
- Publication:
-
Journal of Geophysical Research
- Pub Date:
- November 1989
- DOI:
- 10.1029/JD094iD14p16459
- Bibcode:
- 1989JGR....9416459F
- Keywords:
-
- Aerosols;
- Antarctic Regions;
- Particle Density (Concentration);
- Particle Size Distribution;
- Stratosphere;
- Airborne Equipment;
- Laser Spectrometers;
- Time Series Analysis;
- Atmospheric Composition and Structure: Aerosols and particles;
- Information Related to Geographic Region: Antarctica