EVALUATION OF THE HORIZONTAL MIXING COEFFICIENT IN THE ANTARCTIC CIRCUMPOLAR VORTEX ON THE BASIS OF MEASUREMENTS ON BOARD THE HIGH-ALTITUDE M-55 GEOFIZIKA AIRCRAFT

N. M. Sitnikov, B. M. Kiryushov, V. A. Yushkov, A. E. Ulanovskii, A. N. Luk'yanov, S. M. Khaikin, and F. Ravegnani

The results of water vapor and ozone measurements on board the high-altitude M-55 Geofizika aircraft during the Antarctic campaign under the APE GAIA project in September—October 1999 are presented. Possible causes of air mass dehydration inside the circumpolar vortex are analyzed. Estimates of the horizontal diffusion coefficient inside the circumpolar vortex are calculated on the basis of the difference between measured and calculated water vapor concentrations along the route of the flight. Calculated water vapor concentrations are obtained from the temperature data.