A multi-spectral spaceborne sensor channel device and method for direct inversion of surface temperature

Abstract

The invention discloses a multi-spectral spaceborne sensor channel device and method for directly inverting surface temperature. The channel device comprises a total of 5 channels, and the spectral response function of each channel is determined by a piecewise function composed of a Gaussian function and a trigonometric function. The central wavelengths of the five channels included in the sensorare 8.6, 9.0, 10.4, 11.3, and 12.5[mu]m, respectively. Under the premise that the equivalent noise of each channel is less than 0.1K, the width of the five channels included in the sensor is between 0.1 and 0.5[mu]m. According to the multi-spectral spaceborne sensor channel device and method for directly inverting surface temperature, three sets of combinations of two different channel satellite observation brightness temperature can be obtained based on the channel device. One of the channels in each group of satellite observations brightness temperature can be atmospherically corrected by applying the theory of split window algorithm, then the ground observation brightness temperature of three channels can be obtained. The surface temperature information can be directly obtained from themulti-channel satellite observation brightness temperature by applying the temperature / emissivity separation algorithm without relying on prior knowledge.

Description

technical field [0001] The invention belongs to the technical field of surface temperature remote sensing inversion, in particular to a multi-spectrum spaceborne sensor channel device and method that can be used to directly invert the surface temperature. Background technique [0002] Surface temperature is an important factor describing the energy exchange between the earth and the atmosphere. Together with surface emissivity, it determines the magnitude of surface long-wave radiation. Therefore, surface temperature is of great significance for estimating regional and global energy budgets. Accurate surface temperature products can not only represent the spatial differences of surface radiation, but also reflect the dynamic change process over time. Therefore, many research fields, such as meteorology / climate, evapotranspiration, hydrology, etc., take surface temperature as an important input parameter. [0003] Thermal infrared satellite remote sensing can efficiently obta...

AI Technical Summary

Problems solved by technology

The currently available prior knowledge of surface emission is usually the emissivity product produced based on other satellite data, or estimated from the observation data of the visible light channel. These data are inconsistent with the field of view of the thermal infrared satellite observation channel. The emissivity depends on the type of ground objects in the field of view of the sensor and the ratio between the various types, so it is difficult to guarantee the accuracy of the obtained emissivity prior knowledge; the currently available prior knowledge of atmospheric information is usually the atmospheric information produced based on other satellite data. Profile products, or global atmospheric reanalysis data, the spatial resolution of these products is often low, and more importantly, these products do not necessarily provide atmospheric information at the time of thermal infrared satellite observation, so there is a problem of time mismatch

Therefore, in practical applications, it is difficult to obtain accurate atmospheric information and surface emissivity information matching with thermal infrared satellite observation data, which limits the accuracy of surface temperature based on existing sensor channel devices and corresponding inversion algorithms. The error is often higher than 1.0K

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