Measurements of the size distribution and concentration of the atmopsheric aerosol were made from an instrumented aircraft at altitudes of up to 6 km around New Zealand (37¿S to 46¿S) and during flights to other southwest Pacific islands (to 9¿S). Measurments were also made at the surface in Antarctica (78¿S). Single-particle optical counters were used to cover the size range 0.06 μm to 8.0 μm radius. The results show that the free troposhere aerosol concentration ranged from 1.8 to 46 cm-3 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 move variable, and the size distributions often bimodal. ¿ American Geophysical Union 1989