黔东南暴雨气候特征及其地形影响

利用1960~2000年贵州省黔东南地区降水观测资料,统计分析黔东南地区暴雨时空分布特征,进一步揭示其活动规律及主要影响因素。结果表明:黔东南地区暴雨有显著年代际变化特征,存在准15年的周期变化,并与贵州降水和长江中下游降水呈同位相;存在两个暴雨多发中心,夜间暴雨较多。黔东南暴雨地域分布极为复杂,局地性暴雨较多,这与黔东南特殊地形有着密切关系,地形因素是影响黔东南地区暴雨的重要原因,对形成上述特征的气候学成因做了初步讨论。

Climatic Characteristics of Heavy Rainfall over Southeastern Guizhou Province and Terrain Effect

Using the precipitation data of 18 weather stations in the southeastern Guizhou Province from 1960 to 2000,the temporal and spatial distribution,variation regularities,and influencing factors of heavy rains are analyzed statistically.The results indicate that there is notable interdecadal variation in heavy rainfall over the southeastern Guizhou Province with a quasi-15 year period and the same phase with precipitation variation in the whole Guizhou Province and the middle and lower reaches of the Changjiang River;there are two high-occurrence centers;heavy rainfall occurs more frequently in the evenings;heavy rains are disturbed highly unevenly,mostly local rainfall,which are related to the special topography in the southeastern Guizhou Province.The climatic causes are also discussed.