Anomalously low ozone over the Arctic

Total ozone observations from the Total Ozone Mapping Spectrometer (TOMS) instruments during March 1997 reveal an extensive region of low column densities in the Arctic region centered near the north pole. Values were below 250 Dobson units for nearly a two week period during this period, and were correlated with the position of the northern lower stratospheric polar vortex. The March 1997 average total ozone column densities were more than 30% lower than the average of column densities observed during the 1979–1982 March period.