摘要为了解2009 年8 月莫拉克台风的强大降雨在台湾南部地区引发严重的崩塌,造成500 多人死亡的灾害情况。采用ArcGIS 判释卫星影像崩塌地,统计分析降雨条件包括降雨强度、累积降雨量、降雨延时及重现期距等,对高屏溪流域在莫拉克台风期间之降雨与崩塌进行探讨。结果表明:1)莫拉克台风的降雨特性为长降雨延时(平均为3.3 d)、高累积降雨量(平均为1 677 mm)及高降雨强度(平均为80.5 mm/ h);2)尾寮山雨量站在48 h 之累积降雨量(2 319 mm)接近台湾降雨量纪录(2 361 mm);3)尾寮山、御油山与溪南雨量站降雨延时在10 ~72 h 之间,降雨强度皆大于尾寮山雨量站200 a 之重现期距;4)风灾后新增崩塌面积及新增崩塌率分别为141.24 km2 及4.92%,当累积降雨量达500 mm 或降雨强度达55 mm/ h 时,崩塌地明显增加,崩塌率随累积降雨量及降雨强度的增加而有上升的趋势。
Abstract：The purpose of this study is to discuss the relationship between the heavy rainfall and the massive landslides caused by Typhoon Morakot,which killed more than 500 people in southern Taiwan.The landslide areas induced by the heavy rainfalls were identified by the satellite image analyses and the rainfall conditions, including the rainfall intensity, the cumulative rainfall, the rainfall duration and the return period of the rainfall were also analyzed in Gaoping river watershed during Typhoon Morakot. The results show:1)The rainfall characteristics of Typhoon Morakot are long duration rainfall (mean value= 3.3 d), huge rain accumulation (mean value=1 677 mm) and high intensity rainfall (mean value=80.5 mm/ h);2) The 48-hour rainfall record (2 319 mm) at Welliaoshan station approaches the record in Taiwan (2 361 mm); 3)The estimated return periods of maximum rainfall intensity from 10-hour to 72-hour at Sinan, Welliaoshan, and Yuyoushan stations during Typhoon Morakot well exceeded 200 years of Welliaoshan station; 4) After Typhoon Morakot, the increased landslide areas and landslide rate were 141.24 km2 and 4.92%. The landslide rate increased with the cumulative rainfall and the rainfall intensity.
2012, Vol. 10 
