北半球仲春平流层行星波活动对臭氧总量分布的影响

采用NCEP/NCAR再分析资料和TOMS臭氧总量资料,分析了1979～2003年4月份平流层行星波1波和2波的变化,及其对北半球中高纬臭氧总量分布的影响.结果表明,在通常情况下,4月份平流层中下层行星波1波强于2波,对应的位势高度场在欧亚大陆北部为一低压涡旋,而北美北部为一高压区.此时,从东北亚到北加拿大为臭氧总量的高值区,而北欧至格陵兰一带为臭氧的低值区.但在有些年份,2波比较强时,相应的位势高度场在极地为一明显的低压涡旋,此时在极地附近会出现臭氧低值区.个别年份如1997年,1波在25年中最强,2波也很强,强低涡中心比常年更靠近北极点,在与之位置相同的地方出现了25年中最明显的臭氧洞.还有一些年份,北极地区主要由高压控制,臭氧总量的高值区基本上出现在北极及其附近.

Impacts of stratospheric planetary wave in midspring on total ozone in northern hemisphere

The NCEP/NCAR reanalysis data of April in the northern hemisphere from 1979 to 2003 were used to analyze the variations of stratospheric planetary wave,and its impacts on the distribution of total ozone were discussed together with TOMS total ozone data.The results indicate that wave 1 is generally stronger than wave 2 in April in middle-lower stratosphere,and there is a low pressure over the north of Eurasia while a high pressure lies on the north of North America(Eurasia Low-North America High pattern).The corresponding characteristics of total ozone distributions are that the high values of total ozone are in the region from northeast Asia to north Canada and the low values appear from northern Europe to Greenland.When wave 2 is stronger than normal,the vortex is located virtually over polar region(Polar Vortex pattern),where the total ozone is lower.Especially in 1997,wave 1 was the strongest in 25 years and wave 2 was strong too,so that the vortex was more closer to the north pole and at the same position there was a clear ozone hole.During some years when the north pole was controlled by high pressure(Polar High pattern),the high total ozone mostly appeared at the north pole region.