Measurements of the ozone and water vapor contents in the stratospheric Antarctic cyclone from the high-altitude M55 Geophysica Aircraft

Ozone and water vapor contents simultaneously measured in the stratospheric Antarctic cyclone from aboard the M55 Geophysica high-altitude aircraft during the APE-GAIA Antarctic campaign in September-October 1999 are presented. Examinations of the so-called ozone "hole" showed that, at the height of the ozone stratospheric maximum, the ozone partial pressure was no more than 1 mPa; i.e., it did not exceed the tropospheric ozone partial pressure. A chemically disturbed stratospheric region with a pronounced boundary located at a height of 17 to 18 km and characterized by simultaneous abrupt changes in the concentrations of ozone (by a factor of 6) and water vapor (by a factor of 1.5-2.0) was revealed. It is noted that the existence of the ozone hole was accompanied by air-mass dehydration associated with the observed low temperatures favorable to the formation of polar stratospheric clouds. It is concluded that chemical processes of ozone destruction and dehydration processes proceeded within the same air mass. The stratospheric vertical ozone profiles in the area of the ozone hole were measured.