不同嵌套方式下的积云对流方案对上海崇明极端暴雨高分辨率模拟的影响研究  

Impact of Cumulus Parameterization Schemes with Multigrid Nesting on the High-Resolution Simulation of an Extreme Heavy Rainfall Event in Chongming,Shanghai

作　　者：王瑞[1,2,3] 乔枫雪 丁杨[5] 梁信忠 WANG Rui;QIAO Fengxue;DING Yang;LIANG Xinzhong(Key Laboratory of Geographic Information Science,Ministry of Education,East China Normal University,Shanghai 200241;School of Geographic Sciences,East China Normal University,Shanghai 200241;Shanghai Central Meteorological Observatory,Shanghai 200030;Institute of Eco-Chongming,Shanghai 200062;Shanghai Songjiang Meteorological Service,Shanghai 201613;College of Atmospheric Science,Nanjing University of Information Science and Technology,Nanjing 210044;Department of Atmospheric&Oceanic Science,University of Maryland at College Park,USA;Earth System Science Interdisciplinary Center,University of Maryland,Maryland,USA)

机构地区：[1]华东师范大学地理信息科学教育部重点实验室,上海200241 [2]华东师范大学地理科学学院,上海200241 [3]上海中心气象台,上海200030 [4]崇明生态研究所,上海200062 [5]上海市松江气象局,上海201613 [6]南京信息工程大学大气科学学院,南京210044 [7]马里兰大学帕克分校大气与海洋科学系,美国 [8]马里兰大学地球系统科学跨学科中心,美国

出　　处：《气候与环境研究》2021年第1期58-74,共17页Climatic and Environmental Research

基　　金：国家重点研发计划项目2018YFC1507702;国家自然科学基金项目41605079、41730646。

摘　　要：使用1980~2017年共38年崇明站逐日降水资料对崇明站年降水量及暴雨日数的特征进行分析,并使用中尺度数值预报模式WRF3.9.1.1(Weather Research and Forecasting model)针对崇明年降水量及暴雨日数异常年份2015年的最强降水过程进行数值模拟,结合站点降水观测资料使用统计方法来系统验证模拟结果。通过敏感性试验着重研究尺度自适应的GF(Grell–Freitas)与传统的KF(Kain–Fritsch)、BMJ(Betts–Miller–Janji?)积云对流参数化方案在不同比率的网格嵌套方式下对于本次过程极端降水总量及逐时变化预报的影响。研究结果表明:使用大比率(9:1或15:1)的双层嵌套可以更真实地模拟强降水区累积降水量分布和逐时变化情况,而使用传统的小比率(3:1或5:1)三层嵌套网格会导致大暴雨和特大暴雨的TS(Threat Score)评分降低,小时降水峰值模拟偏弱等问题;模式外圈使用传统的KF、BMJ积云对流方案比尺度自适应的GF方案对于内圈高分辨率的极端降水总量、逐时变化模拟更有优势,特别是使用KF方案,可以更真实地模拟出极端降水中心的日变化强度;而使用GF方案对于入海口降水模拟偏弱,大暴雨和特大暴雨的TS评分普遍偏低,小时降水峰值也被严重低估。This study utilized the observational precipitation data from 1980 to 2017 to analyze the characteristics of annual precipitation and heavy rainfall days at the Chongming station.One extreme heavy rainfall event in 2015 was completely examined using the Weather Research and Forecasting model(version 3.9.1.1)focusing on the impacts of different cumulus parameterization schemes(two traditional schemes,KF and BMJ,and a scale-aware GF scheme)and multigrid nesting configurations.Various statistical methods were adopted to verify the model simulations against the observations.Results showed that using double nesting with a high ratio(9:1 or 15:1)can more realistically produce extreme rainfall distributions and hourly variations compared with the traditional small ratio(3:1 or 5:1)triple nesting grids that produced a lower threat score(TS)for extreme rainfall and underestimated the primary rainfall peaks.On the other hand,the KF and BMJ schemes in the outer grids showed advantages over the GF scheme for the inner 1-km and 3-km simulations of extreme rainfall distribution and hourly rainfall variations.The GF scheme tended to underestimate the extreme rainfall amount over the eastern estuary and TS scores for heavy and extremely heavy rain intensity.

关 键 词：WRF模式 极端降水 嵌套网格 积云对流参数化方案 

分 类 号：P435.1[天文地球—大气科学及气象学]