四川空中水资源的稳定性与可开发性研究

利用1948—2008年的NCEP/NCAR逐月再分析资料,计算了四川地区大气中的可降水量、水汽含量相对变率、水汽输送通量和水汽输送通量散度,分析了四川空中水资源的稳定性与可开发性。结果表明:水汽含量的稳定性特征与水汽含量有密切关系,水汽含量高的东南部,水汽含量稳定;水汽含量相对低的西北地区,水汽含量不稳定。盆地月水汽含量的平均年际变化特点为:夏季小、冬季大,东部小、西部大,1948—2008年以来,区域平均的年大气可降水量总体呈偏多—偏少—偏多—偏少的趋势。大部分水汽集中在对流层中下层,主要来自印度季风区孟加拉湾和南海,而对流层中上层,则以中纬度西风带输送为主。春、秋、冬季四川东南地区有较强的水汽辐合中心,结合大气环流和大气湿度分布揭示了区域上空水汽汇聚,可以较好地指导云雨作业。

Research of Stability and Exploitability of Water Resource in Sichuan

Based on the NCEP/NCAR reanalysis data during the period 1948 to 2008, the precipitable water content of atmosphere, relative variability of water content, moisture flux and moisture flux divergency over Sichuan region are calculated, stability and exploitability of water vapor resource over the Sichuan Basin region are studied. The result indicated: the stable characteristics of water vapor content is closely related to water vapor content, water vapor content is stable in southeastern part of the high water vapor content and is unstable in the northwestern region of the relatively low water vapor content. Time series of yearly atmospheric precipitable water over the Sichuan Basin is that the change in summer is small and winter is great, eastern is small and western is great. From 1948 to 2008, the regional average yearly atmospheric precipitable water presents a tendency of up-down-up-down. Most moisture concentrates in the lower troposphere primarily from the Bay of Bengal and in the mid and upper layers, the vapor flux comes from mid-latitude westerlies as well as the tropical West Pacific Ocean. Southeast of Sichuan is the strongest water vapor convergent region in spring, fall and winter. The climatological distribution and variation of circulation and the atmospheric humidity have revealed advection and convergence of atmospheric water vapor transport over the Sichuan region, so as to instruct artificial precipitation better.