1959-2012年我国极端降水台风的气候特征分析

Analysis on Climatic Characteristics of Extreme Precipitating Typhoon in China During 1959—2012

利用上海台风研究所整编的1959—2012年台风最佳路径和台风日降水资料,采用百分位法确定单站台风极端降水阈值,针对单个台风影响过程中所造成极端降水的影响范围、降水日数和降水强度异常等指数进行逐个评估,建立了极端降水台风综合指数,依据该指数确定了影响我国的57个极端降水台风,并统计分析了这些台风个数及强度的月际分布特征和路径特点。结果表明:台风极端降水阈值在我国呈由东南沿海向西北内陆减小的分布特征。极端降水台风影响我国的路径大致分为两类,一类穿过台湾或经过台湾北部洋面在我国东南沿海登陆,另一类则于华南沿海登陆或在其近海活动。极端降水台风在20世纪60-70年代及2000年以后相对频发,70年代平均综合指数最高。极端降水台风均出现在5—10月,7—8月频次最多。57个台风中达到台风和强台风级别的最多。

Based on percentile analysis, typhoon be Typhoon Institute of China Meteorological Admini st track stratlon phoon-precipitation for all observation stations are defined, data and daily precipi during the period of tation data from Shanghai 1959--2012, extreme ty- uence, precipitation dura- tion and amount anomaly are also evaluated for every typhoon case. A comprehensive index for extreme precipitating typhoon is then established, and 57 cases are determined with their monthly variations and track characteristics being analyzed. The result suggests that the threshold of extreme typhoon-precipitati- on decreases from Southeast China to Northwest China. The track of extreme precipitating typhoon can be classified into two categories, one goes through Taiwan or its northern ocean and lands in southeast coast of the mainland and the other goes by the offshore or lands in South China. Extreme precipitating typhoons occur more frequently in 1960s--1970s and during years after 2000, with the highest frequency in 1970s and they all occur in the period from May to October and have higher frequency in July and August. A- mong the 57 typhoons, the scales of typhoon and severe typhoons occur most.