台湾中部地区短延时降雨强度初步探讨

台湾地区在经历1999年的921地震后,山坡地土体松动严重,仅仅短延时的降雨即有机会引起土石流的发生,而近年微小的降雨条件下即有可能触动土石流发生,因此将台湾中部地区14个测站所测得的台风降雨资料,依照台风降雨强度进行水文频率分析,分析方法采用对数常态分布法、极端值第一类分布法、皮尔逊第三类分布法及对数皮尔逊第三类分布法等4种方法,计算短延时重现期距并绘成降雨强度-延时-频率之分析曲线,再整合各区域土石流潜势溪流的分布情况,分析台风降雨对台湾中部地区所造成之影响.

Preliminary Study of Short- duration Rainfall Intensity in the Central Region of Taiwan

After the 921 Earthquake in 1999, Taiwan had suffered from serious loosening soil o,f hill side, even a short time delay of rainfall may cause debris flow. In addition, in recent years, ting rainfall conditions could also trigger the debris flow. Therefore, the data of typhoon and rainfall measured by 14 stations in the central region of Taiwan were analyzed by hydrological frequency analysis （ depending on the base of the intensity of typhoon and rainfall）. The anal- ysis includes the methods of Log - normal distribution, Extreme - value type I distribution, Pearson type III and Log - Pearson type III distribution. Finally, it is calculated the short delay return period and diagrammed the rainfall intensi- ty - duration - frequency （IDF） curve, and then integrated the regional distribution of potential debris flow torrent to estimate the influence brought by typhoon and rainfall on the central part of Taiwan.