不同台风路径降水台州地形分布差异分析

Topographic Distribution Characteristics of Rainfall along Typhoon Paths in Taizhou

为探讨台州各类台风路径降水地形分布差异,将台州地形划分为海岛、海岸带、平原地区、迎风坡和内陆地区,利用2004~2019年台州自动站观测的71个台风降水资料,分析各类台风路径降水特征。结论如下:1) 各类台风路径下降水量地形分布差异较大,迎风坡最大,平原地区次之;2) 在浙江沿海石浦以南登陆的台风,降水量最大,台风最大降水集中在括苍山系以东临海东部、雁荡山以东黄岩西部以及台州北部华顶山以东三门西部迎风坡地区;3) 台风路径1、2、3的迎风坡降水量尤为明显,主要由于台州位于台风移动路径的右半圆,盛行东南气流,迎风坡等地形对雨量增幅作用最为明显;4) 通过地形敏感性分析发现:东南气流影响下,台州地形,特别是迎风坡地形对台风暴雨有明显增幅作用,面雨量随地形高度的增加而增加,地形加倍时和无地形时平均雨量增减可达三到四成。

In order to explore the difference of topographic distribution of precipitation along different ty-phoon tracks in Taizhou, the typhoon tracks are divided into islands, coastal zones, plains, wind-ward slopes and inland areas according to the topography of Taizhou. The precipitation characteristics of various typhoon tracks are analyzed by using 71 typhoon precipitation data observed at Tai-zhou Automatic Station from 2004 to 2019. The conclusions are as follows: 1) The topographic distribution of downward water volume varies greatly among different typhoon paths, with the largest windward slope and the second place in plain areas;2) the typhoon landing south of Shipu, Zhejiang coast, has the largest precipitation, and the largest precipitation of typhoon is concentrated in the windward slope areas east of the Kuocang Mountain, west of Huangyan, east of Yandang Mountain, and west of Sanmen, east of Huadingshan, north of Taizhou;3) the precipitation on windward slopes of wind paths 1, 2 and 3 is particularly evident, mainly because Taizhou is located in the right half circle of the typhoon’s moving path, southeast airflow prevails, and topography such as windward slope has the most obvious effect on the increase of rainfall;through the terrain sensitivity analysis, it is found that under the influence of southeast air flow, the topography of Taizhou, especially the windward slope topography, has an obvious increasing effect on the typhoon rainstorm, the area rainfall increases with the increase of terrain height, and the average rainfall increases or decreases by 30%~40% when the terrain doubles or when there is no terrain.