三峡水库上游流域大洪峰暴雨天气系统分析

选择三峡水库入库流量代表洪水强度,以长江上游组成宜昌洪水来源的岷沱江、嘉陵江、乌江、宜宾-重庆、重庆-万州、万州-宜昌为主要流域;把出现历史前3名大洪峰的1981年、1998年和2010年汛期作为切入点,针对直接诱发3次大洪峰的暴雨过程,利用长江上游六大流域实况面雨量、宜昌流量和水位,以及NCEP数值产品的客观分析等资料,采用天气分析、波谱分析方法,分析了对流层中低层主要天气系统,以及200 hPa南亚高压和地面冷空气的情况。指出了3次大洪峰暴雨的环流特征、风场特征、超长波和长波特征等,为三峡水库气象保障服务提供了洪峰暴雨的天气背景。

Weather System Analysis of Storm during Flood Peaks in Upper Reaches of Three Gorges Reservoir

Selecting the inflow in Three Gorges Reservoir as the intensity of the flood,the main source of Yichang flood is the upper Yangtze River,including Min River,Jialing River,Wujiang River,Yibin-Chongqing River,Chongqing-Wanxian River,Wanxian-Yichang River.The authors choose the three major historical flood peaks in 1981,1998 and 2010 as an entry point for the large peak storm process analysis.Using the surface rainfall,Yichang flow and water level of the six rivers in the upper Yangtze River and NCEP objective analysis,by the methods of weather analysis and spectral analysis,authors analyzed the main weather systems in lower troposphere,as well as the 200 hPa South Asian high and the ground cold air.The circulation characteristics of the three major historical flood peaks,wind field characteristics,super long wave and long wave characteristics are given.All these provide the weather background of flood peak storm for meteorological services to the Three Gorges Reservoir.