TROPOSPHERIC OZONE ANNUAL VARIATION AND POSSIBLE TROPOSPHERE-STRATOSPHERE COUPLING IN THE ARCTIC AND ANTARCTIC AS DERIVED FROM OZONE SOUNDINGS AT RESOLUTE AND AMUNDSEN-SCOTT STATIONS

The tropospheric ozone annual variation in the northern and southern p olar regions is analyzed from ozone sounding data obtained at Resolute (74.41-degrees-N, 94.59-degrees-W) during a 15-year period (1974-1988 ) and Amundsen-Scott (South Pole) during a 7-year period (1967 1971, 1 986, 1987). Tropospheric ozone is always less abundant in the southern than in the northern polar region. The difference is greatest in spri ng in the tropopause layer where the Arctic ozone mixing ratio can be 5 x as large as the mixing ratio in Antarctica. The phase of ozone ann ual variation above Resolute changes (increases) gradually from the st ratosphere across the tropopause to the middle troposphere. Unlike thi s, the phase of the Antarctic ozone annual harmonic has a discontinuit y in the layer of the changing tropopause level, so that the annual ha rmonic in the upper troposphere, lower stratosphere is 4-to-5 months o ut of phase (earlier) to that above and beneath. Above both the Arctic and Antarctic stations, the ozone mixing ratio and its vertical gradi ent evolve in a similar manner in the wide layer from the lower strato sphere to the middle troposphere. This likely points out that ozone in this layer is controlled from above. An indication of the stratospher ic-tropospheric ozone exchange above Resolute is noted from mid-winter to spring. The analysis of columnar tropospheric ozone changes gives an lower estimate of the cross-tropopause ozone flux up to 5 . 10(10) mol cm-2 s-1. Above the South Pole, the cross-tropopause ozone flux is not usually large. However, in winter, when the tropopause is not str ongly pronounced, it can rise to 4.5 . 10(10) mol cm-2 s-1, but does n ot penetrate into the middle troposphere. There is also some evidence that early in the spring, when the stratospheric ozone ''hole'' is dev eloped, the stratospheric-tropospheric exchange conducts the influence of the ''hole'' into the upper troposphere, where the integrated ozon e destruction is estimated to be 8.10(10) mol cm-2 s-1. Correlation an alysis gives no ozone-tropopause correlation in the Antarctic in winte r, while in other seasons as well as during all seasons in the Arctic, there are negative correlation peaks just above the tropopause.