Method for correcting angular effect of remote sensing surface temperature product

Abstract

The invention relates to a method for correcting the angular effect of a remote sensing surface temperature product. The method comprises: calculating brightness temperatures of 31 and 32 bands of a pixel by using MOD021KM data; acquiring an atmosphere lower-bound temperature Tair, an atmospheric total water vapor content CWV, a sensor observation zenith angle thetav of the pixel; acquiring general split-window algorithm coefficients C, A1, A2, A3, B1, B2, and B3 in a pixel sensor observation direction; determining a zenith emissivity(epsilon 0) of the pixel; calculating a gradient (alpha) anda slope (phi) of the pixel; calculating a local reflection angle (theta 0); acquiring an average emissivity data set of different coverage types of pure pixels on the surface at the sensor observation angles from -65degrees to +65 degrees; acquiring an emissivity difference data set of different observation zenith angles relative to the zenith direction; making the hypothesis of an expression ofemissivity variation the pixel relative to the zenith direction in an observation direction; determining an emissivity expression of the pixel in an observation direction; and calculating a surface temperature (Ts). According to the invention, on the basis of combination of the existing research, data and methods, the pixel-level emissivity directionality model with high universality is provided and can be applied to the angular effect correction of MODIS temperature products.

Description

technical field [0001] The invention relates to the field of thermal infrared remote sensing surface temperature inversion, in particular to a method for determining surface directional emissivity based on multiple MODIS surface temperature emissivity products, and its application in correcting the angle effect of MODIS temperature products. Background technique [0002] Surface temperature is often used to estimate the energy budget of the Earth's atmosphere interface, and it is also an indispensable parameter in many ecological, climate, hydrological and other models. With the advancement of human science and technology, the improvement of productivity, the carbon emissions in the atmosphere have increased greatly, which has exacerbated the greenhouse effect. Global warming has changed from a concept to a fact that can be perceived. Rise, frequent extreme weather. Surface temperature is an important basis for humans to study the law of global warming and predict the trend...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to solve the problem that the correction of the temperature angle effect in the prior art has space limitations and the influence of terrain on thermal radiation has not been taken seriously. Combining the existing research, data and methods, a universal Strong pixel-level emissivity directivity model, and its application in MODIS temperature product angle effect correction

Images