汉江“83·10”致洪暴雨重预报研究

受气象监测及预报能力限制,1983年10月3~6日汉江流域的致洪暴雨过程,普遍未能准确预报,从而对丹江口水库防洪调度形成了很大压力。通过比较2015年和1983年气象监测水平、降雨预报水平,利用中尺度数值模式WRF和区域气候模式Reg CM4分别对"83·10"暴雨过程以及1983年以来与"83·10"相似量级来水天气过程进行模拟,在当前技术条件下,重现"83·10"暴雨预报过程,并研究预报效果。研究表明:2015年气象监测预测水平较1983年有本质提高,中尺度数值模式能够提前3 d预测出该过程,区域气候模式能提前一个月预测出1983年10月上旬降雨集中;在当前技术条件下,充分运用现有各种观测资料,综合应用多种数值预报模式,可使汉江上游大范围强降雨过程基本不会漏报。

Study on re-forecast of "83 . 10" flood-causing rainstorm in Hanjiang River

Most of the weather-forecasters had not accurately forecasted the flood-causing rainstorm process from Oct. 3 to 6, 1983 in the Hanjiang River basin due to the constraints in weather monitoring and forecasting abilities, which exerted great pressure on Danjiangkou Reservior dispatching. The meteorological monitoring and forecasting abilities in 2015 are compared to that in the 1980s. The flood-causing rainstorm process from Oct. 3 to 6, 1983 and the similar weather processes since 1983 in Hanjiang River basin are simulated by mesoscale meteorological model WRF and regional climate model RegCM4. Under current technical conditions, the rainstorm forecasting processes are reproduced and its effects are studied. It shows that the forecasting ability in meteorological monitoring has been enhanced essentially. The analysis indicates that WRF is capable of forecasting this heavy rain process three days ahead and RegCM4 is capable of forecasting the concentration of rainfalls in the early October in 1983 one month ahead. At present, with abundant observed data and results from multiple numerical models, forecasters can hardly fail to forecast heavy rain processes occurring in large area in upper reaches of Hanjiang River.