A Method for Obtaining Surface Broadband Hemispheric Emissivity at Pixel Scale

Abstract

The invention discloses a method for obtaining the emissivity of a wide-band surface hemisphere at the pixel scale, which comprises the following steps: 1) extracting multi-time phase correlation data, wherein the multi-time phase correlation data comprises the emissivity data of the narrow-band surface direction and the observation zenith angle data; 2) parameterizing the surface narrow-band directional emissivity according to the kernel drive model; at the same time, the kernel function of the surface narrow-band directional emissivity is expressed by parameterization. 3) performing pixel-by-pixel calibration on that kernel function weight coefficients of the surface narrow-band directional emissivity; 4) parameterizing the surface narrow-band hemispheric emissivity by using the parameterized expression result of step 2); 5) obtaining pixel-scale surface wide-band hemispheric emissivity. The invention breaks through the limitation that the physical significance of the prior art method is not clear, get rid of the embarrassing situation that the prior art method relies on the hypothesis condition more and the calculation precision is not high, and improves the precision and efficiency of obtaining pixel-scale surface wide-band hemispheric emissivity remote sensing.

Description

technical field [0001] The invention relates to a method, in particular to a method for obtaining the surface wide-band hemispheric emissivity at the pixel scale, and belongs to the field of information technology services. Background technique [0002] Surface emissivity is an inherent property of the surface, which is the ratio of the thermal radiation emitted by the surface to the thermal radiation emitted by a black body at the same temperature, and is related to the surface composition, roughness, water content and other factors. It is of great significance in surface temperature inversion, surface classification, soil formation and erosion, sparse vegetation coverage and change estimation, bedrock mapping and resource exploration, energy balance research, military affairs, etc. However, due to the limitations of the remote sensing load itself, the current surface emissivity can only obtain the emissivity of the surface narrow-band direction corresponding to the load ob...

AI Technical Summary

Problems solved by technology

There are two main defects in the existing methods: First, the difference between the surface emissivity and the hemispheric emissivity is not considered from the physical level, and the physical model for estimating the surface hemispheric emissivity by using the surface emissivity at several angles is not effectively established. Second, assuming that the surface emissivity is a Lambertian surface, ignoring the angle effect of the surface emissivity in the direction of the surface, it will cause a large error for the underlying surface with anisotropic surface emissivity, and it is difficult to obtain an accurate pixel-scale surface wide band Hemispheric emissivity remote sensing products

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