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DOI	10.1016/j.atmosenv.2021.118425
	On the negative polarization's effects at top of atmosphere
	Chen W.; Xu Y.; Fu Q.
发表日期	2021
ISSN	1352-2310
卷号	254
英文摘要	Polarized signal has been proven to be sensitive to the aerosol optical depth and aerosol microphysical parameters. However, in most current applications, the directions of polarization, which are expressed by the sign of polarization, have long been regarded as minor factor. In most remote sensing retrievals, the absolute values of negative polarizations are considered. Therefore, whether this neglection will introduce uncertainty in remote sensing has not been investigated. In this study, TOA polarized reflectances are calculated with the measured surface (with sign) and modeled (without sign) polarized reflectance to obtain the TOA polarized reflectance dataset. Our results suggest that 7% of the surface measured polarized reflectance is negative, while after the vector radiative transfer calculation, this proportion increases to 20–50%. Although correlations between absolute values of measured and modeled data are high (>0.99), when including the effects of the sign, the correlations will decrease to less than 0.5 or even 0.2, and RMSE will increase 10 times. These discrepancies will introduce a lot of uncertainty in polarized remote sensing retrieval when mixed pixels with opposite polarizations for subpixels occur. Furthermore, the same polarization for different objects is another problem when there are both negative and positive polarizations. Our study is particularly important for future applications of polarized signals to obtain accurate and reliable results. © 2021 Elsevier Ltd
关键词	Bidirectional reflectance distribution function Negative Polarization Top of atmosphere
语种	英语
scopus关键词	Aerosols; Distribution functions; Pixels; Reflection; Remote sensing; Absolute values; Bidirectional reflectance distribution functions; Negative; Negative polarization; Polarization effect; Polarized reflectances; Polarized signals; Remote-sensing; Top of atmospheres; Uncertainty; Polarization; aerosol; optical depth; radiative transfer; remote sensing; top of atmosphere; article; atmosphere; calculation; information retrieval; polarization; remote sensing; uncertainty
来源期刊	ATMOSPHERIC ENVIRONMENT
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/248430
作者单位	College of Geoscience and Surveying Engineering, China University of Mining & Technology, Beijing, 100083, China
推荐引用方式 GB/T 7714	Chen W.,Xu Y.,Fu Q.. On the negative polarization's effects at top of atmosphere[J],2021,254.
APA	Chen W.,Xu Y.,&Fu Q..(2021).On the negative polarization's effects at top of atmosphere.ATMOSPHERIC ENVIRONMENT,254.
MLA	Chen W.,et al."On the negative polarization's effects at top of atmosphere".ATMOSPHERIC ENVIRONMENT 254(2021).