Cloud-Type-Dependent 1DVAR Algorithm for Retrieving Hydrometeors and Precipitation in Tropical Cyclone Nanmadol from GMI Data  

作　　者：Linjun HAN Fuzhong WENG Hao HU Xiuqing HU 

机构地区：[1]School of the Environment,China University of Geosciences(Wuhan),Wuhan 430074,China [2]Chinese Academy of Meteorological Sciences,Beijing 100081,China [3]CMA Earth System Modeling and Prediction Centre,Beijing 100081,China [4]Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites,National Satellite Meteorological Center(National Center for Space Weather)of CMA,Beijing 100081,China

出　　处：《Advances in Atmospheric Sciences》2024年第3期407-419,共13页大气科学进展（英文版）

基　　金：funded by the National Key Research and Development Program of China(Grant No.2022YFC3004202);the National Natural Science Foundation of China(Grant Nos.U2142212 and 42105136)。

摘　　要：Understanding the structure of tropical cyclone(TC)hydrometeors is crucial for detecting the changes in the distribution and intensity of precipitation.In this study,the GMI brightness temperature and cloud-dependent 1DVAR algorithm were used to retrieve the hydrometeor profiles and surface rain rate of TC Nanmadol(2022).The Advanced Radiative Transfer Modeling System(ARMS)was used to calculate the Jacobian and degrees of freedom(△DOF)of cloud water,rainwater,and graupel for different channels of GMI in convective conditions.The retrieval results were compared with the Dual-frequency Precipitation Radar(DPR),GMI 2A,and IMERG products.It is shown that from all channels of GMI,rain water has the highest△DOF,at 1.72.According to the radiance Jacobian to atmospheric state variables,cloud water emission dominates its scattering.For rain water,the emission of channels 1–4 dominates scattering.Compared with the GMI 2A precipitation product,the 1DVAR precipitation rate has a higher correlation coefficient(0.713)with the IMERG product and can better reflect the location of TC precipitation.Near the TC eyewall,the highest radar echo top indicates strong convection.Near the melting layer where Ka-band attenuation is strong,the double frequency difference of DPR data reflects the location of the melting.The DPR drop size distribution(DSD)product shows that there is a significant increase in particle size below the melting layer in the spiral rain band.Thus,the particle size may be one of the main reasons for the smaller rain water below the melting layer retrieved from 1DVAR.

关 键 词：cloud-dependent 1DVAR hydrometeor PRECIPITATION GMI DPR 

分 类 号：P407[天文地球—大气科学及气象学]