In March-April 2011, the М-124 ozonometer observations recorded an anomalous decrease in the level of the total ozone (TO) content over Tomsk. The decrease reached 30% as compared with multiyear averages. Based on analysis of satellite measurement data on TO content and temperature, the observed TO decrease over the northern territory of Russia was associated with the ozone destruction in the polar stratosphere due to anomalously low temperatures at heights 20-30 km and with the export of ozone-poor polar air masses to the regions outside the polar vortex. In May 2011, ozone had returned to its multiyear seasonally average values.
total ozone content, time series, anomaly