The Unprecedented Duration of the 2020 Ozone Depletion in the Antarctic

Abstract

Abstract An increase in the duration of the period of high stability of the Antarctic polar vortex in late spring and early summer (November–December), which has been observed over the past 30 years, is observed. This trend is manifested both in the dynamics of the main characteristics of the polar vortex (vortex area and wind speed along the vortex boundary) and in the area of the Antarctic ozone hole. The dynamics of the polar vortex of 2020 is clear evidence of this phenomenon. During that time, unusually high wind speeds along the vortex boundary were recorded throughout the entire period of its existence; anomalous areas of the vortex and the ozone hole were observed from mid-November to December. In addition, the polar vortex existed until the last week of December, which is unprecedented. To analyze the dynamics of the Antarctic polar vortex, we used the method of vortex delineation on the basis of geopotential values, which were determined from the maximum temperature gradient and the maximum wind speed characterizing the boundaries of the vortex.