西昌卫星发射场及周围地区大气可降水量的气候分析

本文利用1974~2010年NCEP/NCAR月平均可降水量再分析资料和同期西昌发射场的实测降水资料,对发射场及周围地区大气可降水量进行气候分析。结果表明,发射场及周围地区大气可降水量具有明显的季节、月际、年际和年代际变化。四季都呈南湿北干的分布,夏季可降水量含量最大,冬季最小。发射场区可降水量分布在整体上大致为西北-东南向的凹字形,具有南北向扩散,东西向阻隔的作用。发射场干、湿年夏季可降水量差异明显,发射场及周围地区可降水量的平均降水转化率也明显不同,这些都影响了发射场降水气候的变化。 

Climate Analysis of Atmospheric Precipitable Water over Xichang Launch Site and its Surroundings

In this paper, the multiyear mean features and their seasonal, monthly, yearly and interdecadal changes for the air column precipitable water ( hereafter PW ) over the Launch Site and its surroundings have been analyzed, utilizing the NCEP's monthly mean precipitable water reanalyzed gridded data and the observed rainfall data from 1974 to 2010. The results show that there exist the obviously seasonal, monthly, yearly and interdecadal changes of the PW over the Launch Site. It shows wetter in the south than that in the north at all seasons. There are maximum PW in summer and the minimum PW in winter. The air column PW over Launch Site presents approximately a southeast - northwestern U - shaped pattern. The monthly variations of PW show the "corridor - barrier" effect of Launch Site. The summer averaged PW displays a marked difference between the wet and dry years. Furthermore, there are apparent differences in the PW conversion rate into precipitation in various parts of the Launch Site and its surroundings. Above all have influenced the precipitation climate change of the Launch Site