CRA40再分析资料在“21·7”极端强降水研究中适用性评估  

Applicability assessment of CRA40 reanalysis data in the study of the extreme heavy precipitation occurred in July,2021

作　　者：陈姝宜 高庆九[1] 谭桂容[1] 孙玉婷 王辰[1] CHEN Shuyi;GAO Qingjiu;TAN Guirong;SUN Yuting;WANG Chen(Key Laboratory of Meteorological Disaster,Ministry of Education(KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/College of Atmospheric Sciences,Nanjing University of Information Science&Technology,Nanjing 210044,China;Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research,Institute of Heavy Rain,China Meteorological Administration,Wuhan 430205,China)

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心/大气科学学院,南京210044 [2]中国气象局武汉暴雨研究所暴雨监测预警湖北省重点实验室,武汉430205

出　　处：《气象科学》2024年第1期82-93,共12页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(42075032)。

摘　　要：本文基于实际观测数据对比分析ERA5、CRA40、CFSR和NCEP/NCAR四套再分析资料在“21·7”极端暴雨研究中的表现,同时采用ERA5作为资料对比的基准,对CRA40在极端暴雨研究中的适用性进行评估。结果表明:(1)四套资料对台风“烟花”、副高等关键环流系统的强度估计均偏低,CRA40与ERA5所分析的高度场流型总体一致,且环流更接近实况。ERA5对200 hPa高空急流的强度估计最高,CRA40与ERA5的差异最小。对流层低层风速的再现能力CRA40与ERA5相当。对于台风“烟花”的加强转折,四套资料均无法再现。(2)925 hPa温度场上,相较其他资料,在青藏高原地区ERA5温度较低,CRA40温度最高,对于弱冷空气侵入河南北部的过程以CRA40与ERA5的结果最为接近。CRA40对水汽通量及其散度的描述与ERA5在分布形势以及数值上较为接近。(3)CRA40与ERA5资料均能刻画出“21·7”暴雨期间郑州站上空良好的动力条件,强度上CRA40基本略弱于ERA5,两套资料所表现出的经向/纬向环流和位涡总体特征一致。Based on actual observed data,a comparative analysis was conducted to assess the performance of ERA5,CRA40,CFSR,and NCEP/NCAR reanalysis datasets in the study of the extreme rainstorm occurred in July 2021.ERA5 data was used as the reference for comparison,and the applicability of CRA40 data was evaluated in the study of extreme rainstorms.Results show that:(1)the intensity estimation on Typhoon“In-Fa”,the subtropical high,and other key circulation systems by the four datasets is consistently lower.CRA40 s analysis of the geopotential height field aligns well with ERA5,and the circulation pattern is closer to the actual conditions.The intensity estimation of the 200 hPa upper-level jet stream is the highest in ERA5,and the difference between CRA40 and ERA5 is minimal.In terms of reproducing the lower-layer wind speed in the troposphere,CRA40 is equivalent to ERA5.None of the four datasets can reproduce the strengthening and turning point of Typhoon“In-Fa”.(2)In the 925 hPa temperature field,compared with other datasets,the ERA5 temperature is lower in the Qinghai-Tibet Plateau region,and the CRA40 temperature is the highest.For the process of weak cold air intruding into the northern part of Henan Province,CRA40 and ERA5 results are the closest.CRA40 s depiction of water vapor flux and its divergence is relatively close to ERA5 in terms of distribution and numerical values.(3)Both CRA40 and ERA5 datasets depict favorable dynamic conditions in the upper atmosphere over Zhengzhou station in July 2021.In terms of intensity,CRA40 is slightly weaker than ERA5,and the two datasets show consistent features in terms of meridional/zonal circulation and vorticity.

关 键 词：CRA40 ERA5 “21·7”暴雨 再分析资料 资料评估 

分 类 号：P458.121[天文地球—大气科学及气象学]