姬大彬等:Water Vapor Retrieval Over Cloud Cover Area on Land Using AMSR-E and MODIS
被阅读 2906 次
2014-10-21

Water Vapor Retrieval Over Cloud Cover Area on Land Using AMSR-E and MODIS
作者:Ji, DB (Ji, Dabin)[ 1 ] ; Shi, JC (Shi, Jiancheng)[ 1 ]
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
卷: 7  期: 7  页: 3105-3116  特刊: SI
DOI: 10.1109/JSTARS.2014.2298979
出版年: JUL 2014
摘要
This study mainly discusses atmospheric water vapor retrieval over cloud cover area on land with the help of a newly developed surface emissivity parameter estimation method in microwave bands. In the retrieval method, the atmospheric water vapor sensitivity parameter-ratio of brightness temperature polarization difference at frequencies 18.7 and 23.8 GHz (Delta Tb-18.7/Delta Tb-23.8)-is used to retrieve water vapor, and the surface emissivity parameter-ratio of surface emissivity polarization difference at frequencies 18.7 and 23.8 GHz (Delta epsilon(18.7)/Delta epsilon(23.8)) that corresponds to Delta Tb-18.7/Delta Tb-23.8-is a key parameter that affects the final precision of retrieved atmosphere water vapor. In order to estimate Delta epsilon(18.7)/Delta epsilon(23.8) in cloudy condition, we first estimated the value of Delta epsilon(18.7)/Delta epsilon(23.8) in clear condition using Advanced Microwave Scanning Radiometer for EOS (AMSR-E) brightness temperature and related MODIS atmospheric products. At the same time, it was found that gradient information derived separately from and Delta Tb-18.7/Delta Tb-23.8 and Delta epsilon(18.7)/Delta epsilon(23.8) has very good correlation with each other. Based on this good correlation, the Delta epsilon(18.7)/Delta epsilon(23.8) in cloudy condition was estimated using corresponding Delta Tb-18.7/Delta Tb-23.8 and adjacent 8 days Delta epsilon(18.7)/Delta epsilon(23.8) in clear condition. With the estimated Delta epsilon(18.7)/Delta epsilon(23.8), we retrieved atmospheric column water vapor using lookup table method in cloudy condition over land. As a validation source data, the SuomiNet GPS-retrieved precipitable water (PW) vapor is used to validate the retrieved water vapor in this study. According to validation, the correlation coefficient of the two is 0.94 and the root-mean-square-error (RMSE) is 4.85 mm. It is a great improvement in water vapor retrieval using microwave in cloud cover area on land.
通讯作者地址: Shi, JC (通讯作者)
 Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China.
地址:
 [ 1 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China