南极爆发性增温后微量气体的分布特征

Distribution of stratospheric tracer gases after the Antarctic sudden warming

利用高层大气研究卫星(UARS)上的卤素掩星试验(HALOE)提供的资料,分析了2002年异常的南极爆发性增温以后的南极附近平流层微量气体的分布.结果表明,这次爆发性增温以后,除南极臭氧洞明显减弱外,南极平流层其他微量气体的分布也发生了很大改变.在沿70°S纬圈的剖面上,2002年微量气体分布表现出明显的2波型特点,与未发生爆发性增温的2003年和2001年(代表通常年份)强的1波型分布特征相比,各种微量气体混合比在纬向分布更加均匀.通过比较还发现,在通常年份极涡所处的位置上,2002年O3和CH4的混合比有所增加,HCl和NO的混合比有所减少,而NO2和H2O在不同高度上的变化特点不同.这与爆发性增温之后极涡和动力输送的变化有关,同时由于增温导致极地平流层云中相关冰相反应的减弱也是一个重要的原因.

The distributions of trace gases in the stratosphere over Antarctica after the unusual Antarctic stratospheric sudden warming（SSW）in 2002 were analyzed by using the data from the Halogen Occultation Experiment （HALOE） on the Upper Atmospheric Research Satellite （UARS）. Results indicate that after the SSW over Antarctica, besides the weakness of the ozone hole, large changes took place in the stratospheric trace gases. In 2002 the trace gases were mixed more evenly latitude-wise, and the distribution of wave number 2 pattern was demonstrated obviously on the height-latitude section along 70°S, compared with the typical distribution of strong wave number 1 in 2003 and other normal years （without SSW）. At the location of the south polar vortex for the normal year, the mixing ratios of O3 and CH4 increased, HCl and NO decreased, but NO2 and H2O did not accord with a given rule at all altitudes over Antarctica in 2002, which was related to the change of the vortex and the dynamical transportation after the SSW, and affected by the reduced polar stratospheric clouds and weakened processes of heterogeneous chemistry.