Estimation of Microwave Atmospheric Transmittance Over China

作者:Shi, LJ (Shi, Lijuan)[ 1,2 ] ; Qiu, YB (Qiu, Yubao)[ 3 ] ; Shi, JC (Shi, Jiancheng)[ 1 ] ; Lemmetyinen, J (Lemmetyinen, Juha)[ 4 ] ; Zhao, SJ (Zhao, Shaojie)[ 5,6 ]

IEEE GEOSCIENCE AND REMOTE SENSING LETTERS

卷: 14  期: 12  页: 2210-2214

DOI: 10.1109/LGRS.2017.2756111

出版年: DEC 2017

摘要

Atmospheric transmittance is an important factor for atmospheric correction in the inversion of land surface parameters. Under nonprecipitating conditions, microwave atmospheric transmittance in the X-, Ku-, and Ka-bands is mainly determined by oxygen, water vapor, and cloud liquid water content. In this letter, radiosoundings from 119 stations in China, performed twice a day from January 2011 to July 2014, were used in the Salonen-Uppala cloud detection algorithm to distinguish cloud layers from layered atmospheric profiles and to estimate the cloud liquid water content therein. The resulting atmospheric transmittances at frequencies of the Advanced Microwave Scanning Radiometer-Earth Observing System over China were estimated using Liebe's millimeter-wave propagation model and Mie theory. Atmospheric transmittance maps were obtained by interpolating the results from individual sites, driving a climatological database for over China, which may be used to correct for atmospheric influence in surface parameter retrievals. The simulated transmittances were validated through a series of on-site field experiments in the North of China. We compared simulated atmospheric brightness temperature with measurements performed in situ using a ground-based radiometer system. The correlation coefficients between the measured and simulated values were 0.97, 0.99, and 0.98, in the X-, Ku-, and Ka-bands, respectively, with a root-mean-square error of 0.6, 1.6, and 9.5 K, respectively.

通讯作者地址: Qiu, YB (通讯作者)

Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Key Lab Digital Earth Sci, Beijing 100094, Peoples R China.

地址:

[ 1 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China

[ 2 ] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

[ 3 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Key Lab Digital Earth Sci, Beijing 100094, Peoples R China

[ 4 ] Finnish Meteorol Inst, Arctic Res Ctr, FIN-00101 Helsinki, Finland

[ 5 ] Beijing Normal Univ, Res Ctr Remote Sensing, State Key Lab Remote Sensing Sci, Beijing 100875, Peoples R China

[ 6 ] Beijing Normal Univ, Sch Geog, GIS, Beijing 100875, Peoples R China