异常分析在长江中下游暴雨分析和预报中的应用  

Raw and Normalized Anomalies to the Analysis and Prediction of the Lower Yangtze River Basin Extreme Rainfall

作　　者：王坤 张树民 李敏[2] 陈铁 丁爱萍 顾沛澍 WANG Kun;ZHANG Shu-min;LI Min;CHEN Tie;DING Ai-ping;GU Pei-shu(Nantong Meteorological Bureau,Nantong 226000,China;Haimen Meteorological Bureau,Haimen 226100,China)

机构地区：[1]江苏省南通市气象局,南通226000 [2]江苏省海门市气象局,海门226100

出　　处：《科学技术与工程》2020年第7期2546-2553,共8页Science Technology and Engineering

基　　金：“北极阁”开放研究基金(BJG201705);江苏省气象局预报员专项基金(JSYBY201608)。

摘　　要：极端天气事件极易造成严重的气象灾害,对人类的生命财产和国民经济建设及国防建设等造成严重损害。使用欧洲中心(ECMWF)的ERA5再分析资料,选择对极端天气有分析和预报有效的原始异常度(RA)和标准化异常度(NA)对南通地区2016年7月11日极端强降水过程进行分析和预报。研究表明,相比于常用的原值场,RA和NA等异常场对分析和预报该次强降水过程更有优势。日常业务中常用的原值场,很难明显给出对极端降水有较好指示意义的预报指标,相比之下,RA和NA这种异常场,可以给出更为有效的极端降水预报指标。这表明,极端降水事件与气象要素的异常部分直接相关。极端降水的落区与位势高度RA和NA的负异常中心接近,湿度的RA和NA正异常出现的时段和位置也与降水出现的时段和位置有较好的相关性,降水强度与湿度和位势高度的RA和NA的异常强度也有一定关系。综合分析不同高度和位置位势高度和湿度的RA和NA,对分析和预报潜在极端天气的落区、强度和出现时段有重要帮助。使用ECMWF的模式预报资料,通过分析不同时效对该次过程的降水和850 hPa位势高度的预报结果,相比于对降水本身的预报,模式对850 hPa位势高度NA场的预报更为稳健,更有利于预报员该次极端降水事件的把握。Extreme weather events are highly susceptible to serious meteorological disasters,causing serious damage to human life and property and national economic construction and national defense construction.Using the ERA5 analysis data of the European Center(ECMWF),the original raw anomaly(RA)and normalized anomaly(NA),which are effective in the analysis and prediction of extreme weather,are analyzed and predicted for the extreme heavy precipitation process of Nantong on July 11,2016.Study shows that RA and NA are more advantageous to analyze and forecast the heavy precipitation process than the commonly used original field.In case of the original field commonly used in daily business,it is difficult to give the forecast skills which has good indication significance to extreme precipitation.In contrast,the distance between RA and NA can give a more effective forecast of extreme precipitation.This shows that extreme precipitation events are directly related to the anomaly of meteorological elements.The extreme precipitation area is close to the negative distance level center of RA and NA with potential height,and the time and position of the occurrence of the RA and NA positive distance of humidity are also closely related to the time and position of precipitation,and the intensity of precipitation is also related to the distance level strength of RA and NA with humidity and potential height.Comprehensive analysis of RA and NA with different height and position of potential height and humidity can give great help in the analysis and prediction of the rainfall area,intensity and occurrence period of potential extreme weather.The model forecast data of ECMWF,is used to analyze the forecast results of different aging on the precipitation of the process and the height of 850 hPa potential.Compared with the forecast of precipitation itself,the model has a more robust forecast of the NA field of 850 hPa potential height,which is more favorable for forecasters to grasp of the extreme precipitation event.

关 键 词：极端降水 异常分析 标准化异常 极端降水预报 

分 类 号：P458.1[天文地球—大气科学及气象学]