中文摘要：

综合利用1978-2011年TOMS（Total Ozone Mapping Spectrometer）和OMI（Ozone Monitoring Instrument）臭氧总量资料,MLS（Microwave Limb Sounder）臭氧廓线资料以及NCEP/NCAR再分析气象场资料,对比研究了近30a南北极臭氧总量的年际变化和季节变化差异,重点分析了2010/2011年冬末春初北极臭氧出现的异常损耗现象,探讨北极春季臭氧低值产生的原因。结果表明：与南极地区一年四季都保持一个臭氧低值中心明显不同,北极臭氧总量的减少则是伴随着整个春夏季（4-8月）,在秋季（10月）达到最低值,冬季（11月-次年2月）北极臭氧快速恢复,这主要是由于南北半球极地地区环流差异和温度差异造成的。南北两极年均O3总量呈下降趋势,两极地区O3总量年际变化最大的季节是春季。近30a,北极在1997和2011年春季（3-4月）分别达到极低值355DU和361DU,但近年来两极臭氧年际变化趋势不明显。2011年春季,北极地区出现的较严重臭氧低值现象从3月中旬至4月中旬持续了近1个月,2010/2011年冬春季平流层低温和臭氧低值对应关系很好。

英文摘要：

By using the satellite total ozone data of TOMS（Total Ozone Mapping Spectrometer） and OMI（Ozone Monitoring Instrument） from 1978 to 2011,the ozone profile data of MSL（Microwave Limb Sounder） in 2011 and NCEP/NCAR reanalysis meteorological data,the total ozone（TO） seasonal and interannual variations over the Polar Regions are studied.The unusual phenomenon of serious Arctic ozone depletion in later winter and early spring of 2010/2011 is emphatically analyzed,and causes of the phenomenon are explored.Results show that there is a climatic low ozone center over Antarctic through the whole year.However,Arctic ozone decreases from spring to summer（from April to August） ,reaches the minimum in autumn（October） and recovers rapidly in winter（from November to next February） .The differences of the TO seasonal variation are due to the polar circulations and the temperatures diversity in the Polar Regions.The interannual variation of annual averaged TO presents a decline trend,with maximum monthly deviations in spring time in the Polar Regions.In recent 30 years,the unusual low TO values in spring time（from March to April） over Arctic occurred in 1997 and 2011 with 355 DU and 361 DU,respectively.But there are no obviously trends in recent 10 years over the Polar Regions.In the early spring of 2011,an unusual low TO occurred and lasted about one month from middle of March to middle of April over Arctic,which corresponded well with extremely low temperature in the stratosphere in winter and spring 2010/2011.