近几年拉萨上空大气臭氧变化特征

利用Brewer分光光谱仪观测资料分析青藏高原拉萨站近几年大气臭氧的变化特征,结果表明,拉萨上空臭氧主要分布在15～35km,反演结果的峰值出现在21～25 km。对比拉萨四季臭氧垂直分布发现,它们在平流层中上层的差异不大,且在36 km以上的分布大致相同,差异主要表现在从地面到21 km,冬春季的臭氧数密度大于夏秋季,近4年来拉萨的年平均臭氧总量的变化不大,臭氧总量的极值出现在冬春季节,臭氧总量的月平均值在8和9月较低,2008年6～9月臭氧低值的持续时间是近几年中最长的,达23 d。

Variation Characteristics of Ozone over Lhasa in Recent Years

The variation characteristics of ozone in Lhasa in recent years were analyzed by using Brewer spectrometer observation data.The results showed that,ozone over Lhasa mainly distributed in 15-35 km,peak value of inversion results is in 21-25 km.Compared with ozone vertical distribution in Lhasa,there are small differences in upper layer of stratosphere.The distribution above 36 km is similar,the difference is mainly from ground to 21 km.The density of ozone in winter and spring is bigger than summer and autumn.The variation of annual average total amount of ozone in Lhasa in recent 4 years is little,the extreme value is in winter and spring.The monthly mean of ozone in Aug.and Sep.is relatively lower,the duration of ozone low value during Jun.-Sep.in 2008 is the longest,up to 23 d.