Total ozone variations at russian antarctic stations. Results of long-term observations

Abstract

The results of observations of total ozone content (TOC) at the Russian Antarctic stations Mirny (66° 34′ N, 93° 01′ E), Novolazarevskaya (70° 46′ S, 11° 50′ E) and Vostok (78° 38′ S, 106° 52′ E) from 1975 to 2017 are presented. Measurements were carried out by filters ozonemeters M-83/M-124. Throughout this period, there have been steady decreases in TOC in spring time. Early 1990s, the average TOC in September and October at Mirny decreased by 70–75 % of its average values for 1975–1980. The effect of the ozone hole and its intensity depend on ozone-depleting substance (ODS) levels, the dynamical processes and variations of temperature in the stratosphere. Considering the slow rate of decrease ODSs concentration, changes in size and depth of ozone hole have been mainly controlled by variations in temperature and dynamical processes. The destruction of the stratospheric circumpolar vortex early spring of 1988 was the reason that the spring negative anomaly of the TOC was not formed at all. A sharp increase of temperature in the stratosphere in the spring of 2002 was accompanied by an increase in the TOC. It led to reduction in the size of the “ozone hole” and even its dividing into two parts at the end of September. Since the early 2000s, there has been a tendency to return the TOC to the values observed in 1970s and to increase its interannual variability in comparison to 1990s.