2010年1月广西冬季暴雨水汽特征分析

Analysis on the Water Vapor Characteristics of Winter Torrential Rain in Jan.2010 of Guangxi

2010年1月21～23日,广西出现连续两天的全区性暴雨天气。本文利用常规资料和NCEP1°*1°再分析资料进行分析,通过分析广西上空的水汽辐合辐散情况、水汽饱和程度以及水汽来源等,揭示这次冬季连续性暴雨产生的水汽特征。分析结果表明,水汽辐合基本位于600hPa以下,850hPa附近水汽辐合最强;强降雨期间广西上空上升运动比较剧烈,上升气流将低空水汽带到高空,因而强降雨期间广西上空的水汽饱和层高达200hPa;强降雨所需水汽来源于西太平洋。

Based on the regular data and NCEP 1×1° from the torrential rain process, which last two days over Guangxi, the convergence, saturation level and sources of water vapor were analyzed to find out the water vapor characteristics of this winter torrential rain. The results show that the water vapor convergence is mainly less than 600 hPa, the strongest moisture convergence is near 850 hPa; the rising motion above Guangxi is severe during the heavy rainfall. The increased flow will carry low water vapor aloft and the water vapor saturation layer over Guangxi reach as high as 200 hPa during the heavy rain. Water vapor required by heavy rainfall comes from west Pacific.