干旱区生态环境知识资源中心(Arid): A multi-sensor approach to retrieve emissivity angular dependence over desert regions

Arid

DOI	10.1016/j.rse.2019.111559
	A multi-sensor approach to retrieve emissivity angular dependence over desert regions
	Ermida, Sofia L.1,2; Trigo, Isabel F.1,2; Holley, Glynn 3; DaCamara, Carlos C.2
通讯作者	Ermida, Sofia L.
来源期刊	REMOTE SENSING OF ENVIRONMENT
ISSN	0034-4257
EISSN	1879-0704
出版年	2020
卷号	237
英文摘要	Land surface emissivity is a directional quantity and most natural surfaces are anisotropic emitters. Experimental studies show that for homogeneous surfaces like bare soils, the emissivity decreases with view angle. Translation of the directionality of emissivity as obtained from experiments or models to satellite spatial scales of kilometers or more is challenging given the natural heterogeneity of the land surface at those scales. We propose a multi-sensor approach to retrieve TIR emissivity angular dependence from satellite observations. The method is based on simultaneous radiance measurements over stable and homogeneous targets, performed by multiple remote sensing platforms in low-earth orbit (MODIS/VIIRS) and geostationary orbits (SEVIRI) with different viewing configurations. In the case of homogeneous scenes, we assume that differences in observed brightness temperatures are exclusively due to differences in the atmospheric optical path and in surface emissivity within each view angle, as surface temperature is the same for both sensors. We then use radiative transfer simulations to derive the emissivity changes between the sensors due to the viewing position. It is shown that emissivity values decrease with view angle for all thermal infrared channels considered, with the highest variations for channel centered at 8.7 mu m, followed by 10.8 and 12.0 mu m, respectively. The MODIS MYD21 product agrees with the multi-sensor approach for the 8.7 mu m channel but shows negligible dependence on view angle for 10.8 and 12.0 mu m bands. Results suggest that the emissivity calibration curve used in the MYD21 algorithm restricts the retrieval of the full angular variation of emissivity at these channels. A sensitivity analysis shows that the proposed multi-sensor method is robust, with reduced impact of the uncertainty of the atmospheric correction on the retrieval. The impact of emissivity angular dependence on retrieved LST may be as high as 3.0 and 1.0 K, respectively, for the GSW and the TES algorithms for angles up to 65 degrees.
英文关键词	Land surface emissivity Anisotropy Angular effects TES Multi-sensor
类型	Article
语种	英语
国家	Portugal ; USA
收录类别	SCI-E
WOS记录号	WOS:000509819300032
WOS关键词	LAND-SURFACE TEMPERATURE ; CANOPY DIRECTIONAL EMISSIVITY ; THERMAL INFRARED EMISSIVITY ; FILTER PHYSICAL RETRIEVAL ; SKIN TEMPERATURE ; MODIS ; VALIDATION ; PRODUCTS ; REFLECTANCE ; SEPARATION
WOS类目	Environmental Sciences ; Remote Sensing ; Imaging Science & Photographic Technology
WOS研究方向	Environmental Sciences & Ecology ; Remote Sensing ; Imaging Science & Photographic Technology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/315438
作者单位	1.IPMA, Lisbon, Portugal; 2.Univ Lisbon, IDL, Fac Ciencias, Lisbon, Portugal; 3.CALTECH, NASA, Jet Prop Lab, Pasadena, CA USA
推荐引用方式 GB/T 7714	Ermida, Sofia L.,Trigo, Isabel F.,Holley, Glynn,et al. A multi-sensor approach to retrieve emissivity angular dependence over desert regions[J],2020,237.
APA	Ermida, Sofia L.,Trigo, Isabel F.,Holley, Glynn,&DaCamara, Carlos C..(2020).A multi-sensor approach to retrieve emissivity angular dependence over desert regions.REMOTE SENSING OF ENVIRONMENT,237.
MLA	Ermida, Sofia L.,et al."A multi-sensor approach to retrieve emissivity angular dependence over desert regions".REMOTE SENSING OF ENVIRONMENT 237(2020).