我国降水的时空变化与暴雨洪涝灾害

THE VARIATION OF PRECIPITATION IN TIME AND SPACE AND HEAVY-RAIN FLOOD DISASTER IN CHINA

本文论述与降水的时空变化相联系的我国暴雨洪涝灾害的主要特征。我国受东亚季风影响明显，暴雨活动频繁。各地的降水分布极不均匀。暴雨（降水）活动具有明显的年代际变化、年际变化、季节性变化和季节内振荡。与之相对应的暴雨洪涝灾害也具有以上的时空变化特征。我国东南部沿海地区受两种不同性质的降水天气——非台风暴雨和台风暴雨的影响，而各沿海省（区）由两者造成的洪涝灾害程度大小也不同。华南地区后汛期中的暴雨洪涝灾害比前汛期的严重。湖南省的降水一年中具有两个峰值，所造成的洪涝灾害也有两个季节性极大值点。

This paper illustrates the general features of the heavy rain flood disaster in China which relates to the variation of precipitation in time and space. China is dominantly affected by Eastern Asia monsoon,heavy rain occures frequently,but the rainfalls are different in different parts.The precipitation of heavy rain has obvious variation for different decades,years,seasons or months,and as a result,so does the heavy rain flood disaster.The Southern coastal area of China is influenced by two different sorts of precipitable weather——nontyphoon typed heavy rain and typhoon typed heavy rain.The damages caused by the two types of heavy rain in the coastal provinces are different.In Southern China,the flood in later rainy season is more severe than that in fore rainy season.In Hunan Province the precipitation has two peak values in a year,and hence the damages resulted from the flood disaster have also two seasonal extreme values in a year.