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Total ozone observations from the Total Ozone Unit (TOU) aboard the Chinese second generation polar orbiting meteorological satellite,Fengyun-3/A (FY-3/A),revealed that total column ozone over the Arctic declined rapidly from the beginning of March 2011.An extensive region of low column amount formed around mid March; monthly mean total column ozone in March 2011 was about 30％ lower than the average observed during 1979-2010.Daily total column density of ozone near the center of low ozone area in mid March was less than 240 Dobson units,about half the total column ozone amount observed during the same period of the prior 10 years.We analyzed total column ozone data from different satellites during 1979-2011.Results show that the Arctic depletion of ozone in spring 2011 was initiated by thc cold polar vortex in the lower stratosphere.The March mean total ozone over the Arctic has shown a decreasing trend over the past 32 years,and its variation is strongly correlated with the polar vortex.A similar low ozone process of spring 1997 was compared to that of 2011,but daily variations of total ozone in March over the Northern Hemisphere in 1997 and 2011 have different patterns.