0−12 Hour QPFs of HRRR-TLE Using Optimized Probability-Matching Method:Taking Hunan Province as an Example  

作　　者：LIU Jin-qing MAO Zi-yi DAI Guang-feng YANG Zhao-li PENG Xuan 刘金卿;毛紫怡;戴光丰;杨兆礼;彭轩(College of Meteorology and Oceanography,National University of Defense Technology,Changsha 410073 China;Hunan Meteorological Observatory,Hunan Meteorological Bureau,Changsha 410118 China;Guangzhou Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction,China Meteorological Administration,Guangzhou 510641 China;Key Laboratory of High Impact Weather(Special),China Meteorological Administration,Changsha 410073 China)

机构地区：[1]College of Meteorology and Oceanography,National University of Defense Technology,Changsha 410073 China [2]Hunan Meteorological Observatory,Hunan Meteorological Bureau,Changsha 410118 China [3]Guangzhou Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction,China Meteorological Administration,Guangzhou 510641 China [4]Key Laboratory of High Impact Weather(Special),China Meteorological Administration,Changsha 410073 China

出　　处：《Journal of Tropical Meteorology》2024年第4期361-372,共12页热带气象学报(英文版)

基　　金：Natural Science Foundation of Hunan Province(2021JC0009);National Natural Science Foundation of China(42375002,42105146);Key Projects of Hunan Meteorological Bureau(XQKJ22A004)。

摘　　要：In real-time operations,the minutely/hourly updated high-resolution rapid refresh(HRRR)system is one of the most expensive numerical weather prediction(NWP)models.Based on a twenty-member HRRR-time-lagged-ensemble(HRRR-TLE)system developed from two real-time convection-permitting HRRR models,CMA-GD(R3)and CMA-SH3,from the China Meteorological Administration(CMA),this study proposes an optimized probability-matching(OPM)technique to improve 0−12 h quantitative precipitation forecasts(QPFs)based on the correlation and error relationships between ensemble forecasts and observations during the training window.Then,a series of sensitivity experiments using different cost functions and optimized ratios was conducted to further improve OPM predictions.The results indicate that:(1)In the HRRR-TLE system,there is no always optimal member in both weak rain and severe rain forecasts,as measured by the equitable threat score(ETS)and bias extent(BE)at four thresholds(1+,5+,10+,and 20+mm h^(-1);e.g.,“1+”means≥1).(2)Compared with the HRRR-TLE system,the QPFs generated by the traditional PM technique showed a notable increase in ETS and a decrease in BE at all of the above thresholds.Compared with the traditional probability-matching method(PM),OPM can generate more skillful forecasts on both spatial representations and rain rates by using the sliding-weight method and optimized ensembles,respectively.(3)In particular,in the 20+mm h^(-1)forecasts,which are often difficult to predict,the ETS of the optimal OPM test,with a 20%optimization ratio and symmetric mean absolute percentage error cost function,increased by 64.6%,and the BE decreased by 5.7%,relative to PM.Moreover,OPM shows good stability in both daytime and nighttime periods.

关 键 词：high-resolution rapid refresh convection-permitting time-lagged probability-matching CMA-GD(R3) CMA-SH3 

分 类 号：P456.7[天文地球—大气科学及气象学]