深对流方案闭合条件变化对全球-区域一体化模式降水模拟的影响  

The Impact of Changes in Closure of Zhang-Mcfarlane Convection Scheme on Precipitation in GRIST Model

作　　者：徐婷 李晓涵 车玉章 彭新东[2,4] 杜宇 XU Ting;LI Xiaohan;CHE Yuzhang;PENG Xindong;DU Yu(College of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610225,China;State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China;2035 Future Laboratory,PIESAT Information Tech-nology,Co.Ltd.,Beijing 100195,China;CMA Earth System Modelling and Prediction Centre,Beijing 100081,China)

机构地区：[1]成都信息工程大学大气科学学院,四川成都610225 [2]中国气象科学研究院灾害天气国家重点实验室,北京100081 [3]航天宏图信息技术股份有限公司2035未来实验室,北京100195 [4]中国气象局地球系统数值预报中心,北京100081

出　　处：《成都信息工程大学学报》2023年第6期689-700,共12页Journal of Chengdu University of Information Technology

基　　金：国家自然科学基金资助项目(42075151、42205160)。

摘　　要：针对全球-区域一体化模式(GRIST)在热带对流降水过多的问题,将Zhang-Mcfarlane(ZM)闭合假设中对流在固定时间内消耗全部对流有效位能(CAPE)改为消耗一定比例的对流有效位能,从而减少对流降水。选取对流消耗95%、90%、80%、75%CAPE进行敏感实验,分析闭合假设变化对降水、云及其辐射效应的影响。结果表明,降水对CAPE消耗比例最敏感。不完全消耗CAPE会减少热带降水,主要表现为减小了赤道东太平洋、亚马逊以及印度尼西亚降水正偏差,其中CAPE95和CAPE90的降水模拟结果与观测更为接近。相比于其他实验,CAPE90消除了秋季的双赤道辐合带,夏季的双赤道辐合带也有所缓解。对流消耗CAPE量减少时,热带太平洋弱降水发生的频率减小且强度增强。相比于降水,云及其辐射效应对对流消耗CAPE量无明显敏感性。The closure in Zhang-Mcfarlane(ZM)deep convection scheme is revised to reduce the excessive tropical precipitation for a Global-to-Regional Integrated Forecast System(GRIST).The closure in the ZM scheme that convection consumes all Convective Available Potential Energy(CAPE)in a specified adjustment time is revised to consume a certain proportion of CAPE.95%,90%,80%and 75%of CAPE were selected for sensitivity experiments and the impact of the revised closure on the simulated precipitation,cloud and radiation is evaluated.The simulation results indicate that the precipitation is highly sensitive to the consumed proportion of CAPE by convection.Incompletely consuming CAPE reduces the precipitation in the tropical regions,such as the positive biases of precipitation in the equatorial eastern Pacific,southeast Pacific,Amazon and Indonesia are reduced.Comparing the sensitivity experiments results,the annual mean of precipitation for 95%and 90%CAPE consumption is closer to the observation.The 90%CAPE consumption simulation alleviates the double ITCZ bias in the autumn and summer.The reducing the amount of CAPE consumption can lead to the frequency of light precipitation reduction and the intensity of light precipitation in the tropical Pacific increase.Compared with precipitation,cloud and its radiation effects have no obvious sensitivity to convective consumption of CAPE.

关 键 词：ZM深对流参数化方案 闭合假设 降水模拟 

分 类 号：P435[天文地球—大气科学及气象学]