地形对超强台风罗莎降水影响的初步分析  

A Study of the Impact of Terrain on the Precipitation of "KROSA"

作　　者：黄奕武[1,2] 端义宏[3] 余晖[2] 

机构地区：[1]中国气象科学研究院,北京100081 [2]中国气象局上海台风研究所,中国气象局台风预报技术重点开放实验室 [3]国家气象中心

出　　处：《气象》2009年第9期3-10,共8页Meteorological Monthly

基　　金：国家重点基础研究发展计划项目2009CB421500;国家科技部科研院所社会公益研究专项2005DIB3J104;国家自然科学基金项目:40730948

摘　　要：为了进一步加深地形对台风降水影响的细节了解,用变分法合成的高分辨率降水资料和地形资料,结合日本再分析资料,对0716号台风罗莎登陆期间地形对降水的影响作了初步分析。过程降水量与地形相关分析表明,沿海地形对降水的影响较大。强降水区主要分布在沿海山体的迎风坡上。分析1小时降水量在不同强度区间的频次分布,发现在山体地形的影响下,山脉区域降水加强。浙江东南沿岸的山体引起的降水增益相对东北沿岸区域的山体偏大。利用日本再分析资料和地形资料计算了气流过沿海山体时的无量纲数Fr值。由于气流Fr较小,气流过浙江沿海地形时更容易翻越山体。抬升位置发生在迎风坡上,因而强降水区也落在迎风坡上。东南沿岸区域的地形对迎风气流的强迫垂直运动在垂直方向上的渗透比东北沿岸区域更深厚,这是导致东南沿岸区域地形对降水增益比东北沿岸区域偏大的原因。The impact of terrain on the precipitation during the landfall of ＂KROSA＂ （0716） was analyzed with reanalysis data of JMA, topography data and the high resolution rain data generated by the variation method. The correlation coefficient between total precipitation and topography indicated that the terrain over Zhejiang largely affected the precipitation. The peak rainfall is located mainly on the windward hillsides. The distribution of frequency of different precipitation ranks showed that the relatively stronger precipitation happened in the topographic regions. The rain gains caused by the mountains along the southeastern coast of Zhejiang were more than those caused by mountains along northeastern coast. With the reanalysis data of JMA, the nondimensional number of flow crossing the topography was counted. As the value of Fr was small in this case, the air could flow over the hills more easily. The forced upward motion occurred windward in association with the heavy precipitation. The forced vertical velocity penetrated more deeply in southeastern coast than in northeastern coast, which might be the reason that the rain gains in southeastern coast were more than in northeastern coast.

关 键 词：超强台风罗莎 地形 强降水过程 无量纲数Fr 

分 类 号：P426.615[天文地球—大气科学及气象学] TP391.72[自动化与计算机技术—计算机应用技术]