Understanding and improving Yangtze River Basin summer precipitation prediction using an optimal multi-Physics ensemble  

作　　者：Yang ZHAO Fengxue QIAO Xin-Zhong LIANG Jinhua YU 

机构地区：[1]Climate,Environment and Sustainability Center,Nanjing University of Information Science and Technology,Nanjing 210044,China [2]Key Laboratory of Geographic Information Science(Ministry of Education),East China Normal University,Shanghai 200241,China [3]School of Geographic Sciences,East China Normal University,Shanghai 200241,China [4]Department of Atmospheric and Oceanic Science,University of Maryland,College Park MD 20740,USA [5]Earth System Science Interdisciplinary Center,University of Maryland,College Park MD 20740,USA [6]Key Laboratory of Meteorological Disaster(KLME)(Ministry of Education)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD),Nanjing University of Information Science and Technology,Nanjing 210044,China

出　　处：《Frontiers of Earth Science》2024年第1期256-277,共22页地球科学前沿（英文版）

基　　金：funded by the US National Science Foundation Innovations at the Nexus of Food,Energy and Water Systems(US-China INFEWS)under Grant EAR1903249;the China Meteorological Administration/National Climate Center research subcontract 2211011816501;the the Shanghai 2021“Scientific and technological innovation action plan”Natural Science Foundation(Grant No.21ZR1420400).

摘　　要：This study employs the regional Climate-Weather Research and Forecasting model(CWRF)to first investigate the primary physical mechanisms causing biases in simulating summer precipitation over the Yangtze River Basin(YRB),and then enhance its predictive ability through an optimal multi-physics ensemble approach.The CWRF 30-km simulations in China are compared among 28 combinations of varying physics parameterizations during 1980−2015.Long-term average summer biases in YRB precipitation are remotely correlated with those of large-scale circulations.These teleconnections of biases are highly consistent with the observed correlation patterns between interannual variations of precipitation and circulations,despite minor shifts in their primary action centers.Increased YRB precipitation aligns with a southward shifted East Asian westerly jet,an intensified low-level southerly flow south of YRB,and a south-eastward shifted South Asian high,alongside higher moisture availability over YRB.Conversely,decreased YRB precipitation corresponds to an opposite circulation pattern.The CWRF control configuration using the ensemble cumulus parameterization(ECP),compared to other cumulus schemes,best captures the observed YRB precipitation characteristics and associated circulation patterns.Coupling ECP with the Morrison or Morrison-aerosol microphysics and the CCCMA or CAML radiation schemes enhances the overall CWRF skills.Compared to the control CWRF,the ensemble average of these skill-enhanced physics configurations more accurately reproduces YRB summer precipitation’s spatial distributions,interannual anomalies,and associated circulation patterns.The Bayesian Joint Probability calibration to these configurations improves the ensemble’s spatial distributions but compromises its interannual anomalies and teleconnection patterns.Our findings highlight substantial potential for refining the representation of climate system physics to improve YRB precipitation prediction.This is notably achieved by realistically coupling cumul

关 键 词：physics parameterization regional climate model downscaling skill enhancement multi-physics ensemble TELECONNECTION bias reduction 

分 类 号：P45[天文地球—大气科学及气象学]