Aerosol and ozone observations in the polar troposphere at Spitsbergen in spring 1994

The dynamics of the tropospheric ozone distribution during the transition from polar night to polar day has been investigated in Ny إlesund, Spitsbergen (79°N, 12°E) in the period from March to June 1994. Surface ozone, the vertical ozone stratification as well as aerosols were measured. Surface 03 mixing ratios were found to be highest in March during prevailing advection from East Europe, while the lowest surface ozone amounts were observed in late June. The transition from winter to spring was characterized by striking surface ozone variations. In this period we observed five distinct 03 minima. Such events were typically associated with advection of marine polar air masses. The low burden of aerosols within the accumulation mode coinciding with low ozone mixing ratios suggests that 03 destruction occurred during long transport times in the remote marine Arctic, largely in absence of anthropogenic pollutants. It was found that the 03 depletion was restricted to the boundary layer only. Typically a capping inversion defined the upper limit of its vertical extension.