The Vertical Distribution and Trends of the Trace Gases in Stratosphere over China

Abstract In order to provide some useful data for studies on radiative and chemical processes in the stratosphere, the vertical distribution of trace gases (NO, NO2, HCl, HF, CH4, H2O and O3) and their variation trends in the stratosphere over China have been analyzed by using the HALOE data from 1992 to 2005. Besides the mixing ratio of the traces averaged over China, the values averaged over Qinghai‐Xizang Plateau are also given. The analyses show that the mixing ratios for various trace gases distribute vertically in different patterns in stratosphere, the distribution and seasonal variation of the traces near tropopause are much different from those in stratosphere, The analyses also show that the seasonal variation, the quasi‐biennial oscillation (QBO) signals and the long‐term trends are clear for all the traces, and the trends of the traces gases in various levels of stratosphere are different. In middle stratosphere, the mixing ratios of NO, NO2, HCl and H2O are all increased before 1998 and then decreased after 1998, while it is contrary for mixing ratio of O3 which decreased evidently before 1998 and the decrease trend is not significant after 1998. That means the decrease of those traces lead to the ozone depletion retarded in middle stratosphere in recent years. While in the lower stratosphere, the ozone depletion is still significant.