以TCCIP資料分析臺灣降雨的氣候特徵與長期變化

本研究利用科技部臺灣氣候變遷推估與資訊平台計畫所提供的再分析降雨資料，探討1970-2015年臺灣降雨的時空氣候特徵與長期變化趨勢。結果顯示，臺灣有近70%的降雨量集中在5-6月的梅雨季和7-9月的夏（颱風）季，日雨量超過200毫米的強降雨有70%以上集中在夏季。從空間分布來看，主要降雨區除了東北部沿海外，其餘均分布於山區，包含雪山山脈、阿里山山脈、玉山山脈和中央山脈等。從長期變化來看，降雨量於1998年之後有增加趨勢，不同等級大雨發生頻率和降雨強度則於2000年後明顯增加（增強），尤以2004-2009年間特別明顯，降雨增加區域則集中在中南部山區（嘉義至屏東間）。

Keywords

降雨；大雨；頻率；強度

Parallel abstracts

The rainfall reanalysis dataset funded by the Taiwan Climate Change Projection and Information Platform has been used to examine the climatology and the long-term trend with their temporal and spatial distributions from 1970 to 2015. It has been found that about 70% of the total annual rainfall amount was observed during the summer season. In Taiwan, the early-summer rainy season from May to June is called the Mei-Yu season, while the late-summer rainy season from July to September is called the typhoon season. According to the results of this dataset, more than 70% of extremely heavy rainfall events (≧ 200mm/day) occurred in the typhoon season during the studied period. In the spatial distribution analysis, the major rainfall regions include the Northeast Coast and the mountain regions, such as Hsuehshan Range, Alishan Range, Yushan Range, and throughout the Central Mountain Range. For long-term trend evaluation, the evidence indicated that the trend has been found to rise since 1998. Furthermore, the occurrence and intensity of the heavy rainfall events have been increasing since 2000, especially during 2004-2009, while the active regions concentrated on the southern Taiwan (between Chiayi and Pingtung).