Aerosol size distributions in the Southwest Pacific

Measurements of the size distribution and concentration of the atmospheric aerosol were made from an instrumented aircraft at altitudes of up to 6 km around New Zealand (37 deg S to 46 deg S) and during flights to other southwest Pacific islands (to 9 deg S). Measurements were also made at the surface in Antarctica (78 deg S). Single-particle optical counters were used to cover the size range 0.06 microns to 8.0 microns radius. The results show that the free troposphere aerosol concentration ranged from 1.8 to 46/cu cm and the size distribution was characterized by a Junge slope around -3.5. In the planetary boundary layer, including Antarctica, the concentrations were generally greater and more variable, and the size distributions often bimodal.