The diurnal variation of polarization characteristics of the Earth treated as an exoplanet

作     者：Shuang Wang Zhong-Quan Qu Hao Li 

作者机构：Yunnan ObservatoriesChinese Academy of SciencesKunming650011China University of Chinese Academy of SciencesBeijing100049China Center for Astronomical Mega-ScienceChinese Academy of SciencesBeijing100101China 

出 版 物：《Research in Astronomy and Astrophysics》 (天文和天体物理学研究（英文版）)

年 卷 期：2019年第19卷第8期

页      面：115-122页

核心收录：

学科分类：0709[理学-地质学] 07[理学] 0708[理学-地球物理学] 070401[理学-天体物理] 0825[工学-航空宇航科学与技术] 0704[理学-天文学] 

基　　金：sponsored by the National Natural Science Foundation of China (NSFC) (Grant Nos. 11527804  10943002 and 11373023) 

主　　题：techniques:photometric methods:data analysis Earth 

摘      要：The diurnal polarization variation of the Earth, treated as an exoplanet with an unresolved disk but resolvable from its host star, is presented in three wavelength bands centered at 490 nm, 670 nm and865 nm respectively according to French satellite-borne PARASOL data. We aim to estimate disk-integrated polarization of the Earth with a phase angle of 55?. It is shown that:(1) the linear polarization signal and its variation are ascribed to the combination of surface feature distribution and atmospheric conditions acting as a variable polarimetric modulator;and(2) the polarimetric wavelength dependence is strong due to the atmospheric wavelength sensitivity. During the period when the PARASOL data were acquired, the cloud coverage ranged from 44.0% to 57.7%, and the polarimetric diurnal variation amplitude was within 1.8%in the 490 nm band, 1.3% in the 670 nm band and 1.5% in the 865 nm band.