摘要
This study uses rain gauge observations to assess the performance of different radar estimators R(ZH),R(KDP)and R(A)in estimating precipitation based on the observations of an S-band polarimetric radar over southern China during a typical convective storm and an extremely severe typhoon,i.e.,Typhoon Manghkut.These radar estimators were derived from observations of a local autonomous particle size and velocity(Parsivel)unit(APU)disdrometer.A key parameter,alpha(α),which is the ratio of specific attenuation A to specific differential phase KDP with three fixed values(α=0.015 dB deg^(-1),α=0.0185 dB deg^(-1)andα=0.03 dB deg^(-1))was examined to test the sensitivity of the R(A)rain retrievals.The results show that:(1)All radar estimators can capture the spatio-temporal patterns of two precipitation events,R(A)withα=0.0185 dB deg^(-1)is well correlated with gauge measurement via higher Pearson’s correlation coefficient(CC)of 0.87,lower relative bias(RB)of 16%,and lower root mean square error(RMSE)of 17.09 mm in the convective storm while it underestimates the typhoon event with RB of 35%;(2)R(A)withα=0.03 dB deg^(-1)shows the best statistical scores with the highest CC(0.92),lowest RB(7%)and RMSE(25.74 mm)corresponding to Typhoon Manghkut;(3)R(A)estimates are more efficient in mitigating the impact of partial beam blockage.The results indicate thatαis remarkably influenced by the variation of drop size distribution.Thus,more work is needed to establish an automated and optimizedαfor the R(A)relation during different rainfall events over different regions.
作者
ZHANG A-si
HUANG Chao-ying
CHEN Sheng
ZHANG Peng-fei
HU Dong-ming
XIAO Liu-si
张阿思;黄朝盈;陈生;ZHANG Peng-fei;胡东明;肖柳斯(School of Atmospheric Sciences/Key Laboratory of Tropical Atmosphere-Ocean System,Sun Yat-sen University,Zhuhai,Guangdong 519000 China;Southern Laboratory of Ocean Science and Engineering,Zhuhai,Guangdong 519000 China;Cooperative Institute for Mesoscale Meteorological Studies,University of Oklahoma,and NOAA/OAR/National Severe Storms Laboratory,OKC 73072 USA;Guangzhou Meteorological Observatory,Guangzhou 511430 China)
基金
National Natural Science Foundation of China(41875182)
Guangzhou Science and Technology Plan Projects(201904010162)
Sun Yat-sen University“100 Top Talents Program”(74110-18841203)
International Program for Ph.D.Candidates at Sun Yat-sen University
作者简介
ZHANG A-si,Ph.D.,primarily undertaking research on radar quantitative precipitation estimation;Corresponding author:CHEN Sheng,e-mail:chensheng@mail2.sysu.edu.cn
