西南地区空中云水量分布特征及变化趋势

为了能更好的合理开发空中水资源,采用NCEP 1980~2009年云水量的逐月再分析资料,通过统计和EOF分析等方法,研究了30年来西南地区(云南、贵州、重庆、四川)云水量的时空分布特征和变化趋势。结果表明:西南地区年和季节云水量分布均具有明显的地区性差异,东南多,西北少,最小值出现在四川西部高原地区;云水量在夏季最多,春季略高于秋季,冬季最少;逐月云水量呈近似的正态分布,1月到6月逐渐增加,7月到12月逐渐减少;西南地区云水量的空间变化既存在南部与北部相反的变化趋势,也存在整体一致型。

Distribution Features and Trend of Cloud Water in Southwest Area

To make better development of water resources in the air, with NCEP monthly cloud water data from 1980 to 2009, spatial and temporal distributive characters and variation trend of cloud water in southwest area are analyzed in this paper by using statistical and EOF analysis. The research shows that the distributions of annual and seasonal cloud water in southwest area have obviously regional differences. There is more cloud water in Southeast region and less in Northwest region. The western Sichuan plateau has the least cloud water. Cloud water varies seasonally, be- ing the greatest in summer, next in spring, lastly in autumn, and least in winter. There is a normal distribution of cloud water in a year, increasing from January to June and decreasing from July to December gradually. The spatial distribution of annual precipitable water not only has regional variations, but also has the coherence in the whole area.