上对流层-下平流层交换过程研究的进展与展望

上对流层和下平流层(UTLS)区域的高度范围大致为5～20 km.UTLS区域大气成分的分布及变化对于认识气候长期变化也极为重要,因为该区域的臭氧是一种有效的温室气体,其中的水汽、卷云和气溶胶对太阳短波辐射和地球长波辐射有很强的调制作用,因而对于天气和气候变化产生不可忽略的辐射强迫作用; UTLS区域中,还有航空业的飞机排放,强对流云云中与云上闪电产生相当量的NOx,这些都对UTLS区域乃至更高及更低层大气的化学成分与分布产生重大影响.该文介绍上对流层和下平流层区域的交换过程研究的意义和手段,同时介绍有关研究的进展,重点回顾近年来国内一些学者开展的工作.另外,还列举一些研究问题和方向,最后重点展望青藏高原上空上对流层-下平流层区域的研究,因为该地区UTLS交换过程不仅具有显著区域特征,而且在全球平流层-对流层交换中可能有重要贡献.

Advances and Prospects in the Study of Stratosphere-Troposphere Exchange

The range of upper troposphere and lower stratosphere(UTLS) is about 520 km.The distribution and change of atmospheric constituents in UTLS are crucial in understanding the climate change.In this region,ozone is an effective greenhouse gas,and water vapor,cirrus cloud and aerosol have important radiative forcing on the weather and climate variation by actively adjusting the solar radiation and long-wave radiation.Aircraft emission and lightning in the strong convection clouds producing considerable NO_x take place in UTLS,which greatly impact the structure of atmospheric constituents in UTLS and upper and lower layers.In this paper,the scientific issues and research methods in the study of stratospheretroposphere exchange(STE) are introduced,and some advances in related fields,especially domestic works in recent years,are summarized.Some key issues and prospects are also discussed.Finally,some expected researches are emphasized in the study of UTLS over the Tibetan Plateau,because the STE processes in this region not only have some significant regional features,but also play potentially an important role in the global STE.