An Effective Modis Surface Temperature Angle Correction Method

Abstract

The invention discloses an effective MODIS surface temperature angle correction method, which comprises the steps of 1, preliminarily building an input data set; 2, selecting end member based information model, decomposing an uncorrected temperature of mixed pixels, and acquiring temperatures of vegetation and soil components; 3, determining a reflectivity calculation model, and performing reflectivity angle correction; and 4, acquiring angle corrected vegetation coverage on the basis of reflectivity angle correction; 5, and acquiring a surface temperature of the mixed pixels after angle correction by combining the angle corrected vegetation coverage through using the vegetation and soil temperatures acquired by decomposing the uncorrected mixed pixel temperatures. By adopting the scheme, temperature values acquired by different pixels of the same landscape image are enabled to be an observed value after angle correction, thereby having comparability, and improving the practical value of a surface temperature acquired by remote sensing.

Description

technical field [0001] The invention belongs to the technical field of surface temperature remote sensing inversion, in particular to an effective MODIS surface temperature angle correction method. Background technique [0002] Surface temperature is an important characteristic physical quantity that characterizes changes in surface processes, and is a direct driver of surface-atmosphere energy exchange, which combines the results of the interaction between the surface and the atmosphere and the energy exchange between the atmosphere and the land. Accurate estimation of surface temperature can provide information on the temporal and spatial changes of surface energy balance, which not only helps to evaluate surface energy and hydrological balance, thermal inertia and soil moisture, but also helps to obtain global surface temperature and long-term changes. Therefore, the surface temperature It is widely used in research fields such as surface energy balance, climate change an...

AI Technical Summary

Problems solved by technology

However, due to the spatial heterogeneity of surface temperature, it is difficult to obtain the temporal and spatial distribution of surface temperature on a regional and global scale, and it is difficult to achieve conventional fixed-point observations on the ground. Satellite remote sensing is a very effective means

[0003] At present, a major problem in obtaining the surface temperature by means of remote sensing is that the surface is usually regarded as a homogeneous body, and the directionality of the surface temperature itself is often ignored in the inversion process

For a uniform surface, this assumption is reasonable; but for a mixed pixel with a non-uniform surface coverage, it has a complex internal structure and different components, and the proportion of each component in the pixel is different under different viewing angles. At the same time, the multiple scattering between each component also makes the emissivity of the pixel depend on the observation direction, and the thermal radiation of the same temperature pixel also shows a certain angle effect

For large-angle observation sensors (such as MODIS, AVHRR), different pixels correspond to different observation angles, and the angle effect of temperature will lead to the lack of comparability of the temperature of different pixels in the same scene image retrieved from the observation data, thus affecting remote sensing acquisition. The use of vegetation and soil temperature

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