SIMULTANEOUS BALLOONBORNE MEASUREMENTS OF STRATOSPHERIC WATER-VAPOR AND OZONE IN THE POLAR-REGIONS

Vertical profiles of stratospheric water vapor and ozone were measured together at McMurdo and South Pole Stations in Antarctia, and at Kiruna, Sweden, on several occasions during the austral spring of 1990 and the boreal winter of 1991. The Antarctic data indicated that major dehydration had occurred on a continental scale over the winter stratospheric cloud formation period leaving only 2 to 3 ppmv water vapor between 11 and 19 km. Measurements before and after movement of the boundary of the polar vortex across McMurdo detected increases in both water vapor and ozone in the 17 to 20 km region. This injected layer was still observed at South Pole Station a month later suggesting continental proportions. In early November, with the vortex still intact, South Pole measurements indicated a substantial degree of inhomogeneity in both water vapor and ozone in the lower stratosphere. In comparison, stratospheric water vapor measurements in the Arctic gave values of 4 to 5 ppmv indicating the absence of the gross stratospheric dehydration effects obvious in the Antarctic, and they did not reveal significant structure except on one occasion with very cold temperatures (-90-degrees-C) at 25 km and nacreous cloud displays.