2011-01-012024-05-14https://scholars.lib.ntu.edu.tw/handle/123456789/657476摘要：過去造成台灣地區豪大雨的颱風，如2009莫拉克，造成豪大雨的幾項因素有: （1）夏季大範圍西南季風爆發以及秋冬季背景場盛行東北季風時，颱風環流與背景風場共伴效應。西南季風爆發時期颱風結構較不對稱，颱風南邊或西南邊的對流，相對於北邊及東北邊厚實或強度稍強； （2）颱風登陸後的移動速度的變慢。造成台灣地區嚴重災情的颱風個案，通常會在登陸後減慢移動速度； （3）在陸期間及離陸後颱風如果移行速度較慢，颱風本身環流與背景場盛行東北季風或是西南季風共伴，配合台灣地形提供舉升機制，造成豪大雨。如西南季風爆發期間易造成台灣地形西側線狀中尺度對流，這些對流具有生命期長與近似滯留的特徵，導致台灣西部或西南部的豪大雨。 計畫研究的重點在於：探討產生豪雨的機制，包含地形影響颱風移速，以及颱風與跨尺度（西南風尺度與中尺度對流）交互作用，計畫擬進行地形與跨尺度影響的颱風豪雨診斷、分析與分類。本計畫將透過搜集分析過去侵台並登陸颱風定位資料與中央氣象局雨量資料，進行統計特徵的分析，找出颱風侵台時降雨與颱風移速變化，颱風強度、颱風登陸位置之間關係，並透過數值實驗找出相關之理論模式。預計也將研究成果與過去颱風移速研究成果結合，供預報員參考並增進預報準確度。 <br> Abstract: The characteristics of typhoon with abnormally heavy rainfall are: (a) The background southwest wind in summer and northeast wind in autumn and winter will interaction with typhoon circulation. For example, the flourish asymmetric convection structure in the south and southwest side of typhoon may be due to background southwest wind. (b) The slowdown of typhoon translation speed over terrain. Slow moving typhoons are usually accompanied with heavy rainfall and make serious disasters in Taiwan. (c) The interaction between background southwest wind or northeast wind and the circulation of slow moving typhoon. The convergence and terrain forcing lifting at southwest area of Taiwan are favorable to produce long life mesoscale convection cells with abnormally heavy rainfall. This proposal focuses on the heavy rainfall mechanism, including terrain effect to typhoon translation speed and interaction between southwest wind and terrain lifting convection. According to the statistic analysis of past typhoon position data and rainfall data and numerical model experiments (with WRF model), we will construct a conceptual model and discuss the importance of several factors. For example, typhoon translation speed, typhoon intensity, typhoon landfall location, etc. This research will also integrate with previous typhoon speed research project in order to benefit to forecasting.颱風降雨異常登陸颱風移速異常地形舉升豪雨abnormally TC rainfallabnormally TC speedterrain forcing rainfall