根据福建南部沿海气象站和水文站1961—2007年降水资料,分析其暴雨特征,应用概率论方法和水文气象法,推求福建南部沿海24 h可能最大降水。结果显示:①福建南部沿海的暴雨主要集中于春夏两季,冷暖空气交绥的锋面暴雨以及台风等热带天气系统所致的暴雨是福建南部沿海最主要的两种暴雨类型。即使同处暴雨一致区,暴雨强度及出现的区域也有一定的偶然性。②采用皮尔逊-Ⅲ型法计算不同重现期24 h的最大降水量时,如果不考虑降水的随机性,不做暴雨一致区的特大暴雨移置和特大值处理,将会影响概率论法计算结果的合理性。③暴雨模式的拟定是整个工作的基础,所选暴雨模式中地形对降水有显著的增幅作用,可认为是高效率暴雨模式,故选择水汽放大法计算,与概率论方法比较,计算结果是合理的。
Based on the heavy rain data from 9 stations along the coastal areas of the southern Fujian from 1961 to 2007,the characteristics of heavy rainfall are analyzed,and the 24-hour Probably Maximum Precipitation(PMP) is calculated for the area by using the probability method and the hydro-meteorological method.Results show:(1) In the coastal area of the southern Fujian,heavy rains mostly happen in spring and summer,and there were two dominating types: frontal rainstorm and typhoon rainstorm;even though in a homogenous region,the intensity and areas of heavy rains are random.(2) The calculated PMP with Pearson-Ⅲ distribution is not reasonable unless the extraordinary heavy rains and their frequency are considered and calculated.In addition,the randomicity of rainstorms must be taken into account in order to insure the correctness of calculated results.(3)The chosen heavy rain model belongs to high-efficiency precipitation,so PMP was calculated with the vapor magnification method.The calculated results,compared with the results of the probability method,are reasonable.