We report on the meteorological analysis and interpretation of ozone profiles carried out by electro chemical concentration cell sondes in July 1989 from the station of Ny ¿lesun, Spitsbergen (79 ¿N, 12 ¿E). The soundings have been compared to other summertime ozone observations in the Arctic area. The data reveal strong day-to-day variations in ozone concentrations, especially near the 23 km level, where the minimum, mean and maximum ozone concentration values were 2.5, 3.25, and 3.75 ppmv, respectively. The possible role of horizontal and vertical advection and photochemistry in creating these variations were analyzed. The very small vertical movements do not explain these deviations. The gradually decreasing average ozone concentrations seem to be a balance between vertical and horizontal advection and chemical net loss. Trajectory analysis demonstrated the existence of two distinct circulation modes explaining the observed variations of ozone concentrations. During calm periods or southeastward advection the ozone concentrations decreased, starting from higher levels, whereas ozone concentrations increased rapidly when large-scale circulation systems advected ozone-rich air from the south. ¿ American Geophysical Union 1992