A Retrieval Method of Optical Depth of Martian Atmospheric Dust Aerosol

Abstract

The invention discloses a Martian atmospheric dust aerosol optical depth retrieval method. The method comprises the steps of performing calibration on MEX-PFS data to obtain PFS observation radiance data and observation noises; performing sensitivity analysis on factors including dust aerosol, atmospheric temperature, carbon dioxide, surface temperature and surface emissivity, and selecting a dustaerosol retrieval spectrum section; by using a surface emissivity real value, an atmospheric background data initial value and a surface temperature initial value, generating a Martian atmospheric state vector initial value; at the dust aerosol retrieval spectrum section, calculating atmospheric layer top outgoing radiance under the atmospheric state vector initial value condition, and adding theobservation noises to obtain simulated PFS radiance; and retrieving an atmospheric state vector, and cyclically calculating the simulated PFS radiance to minimize a cost function. According to the method, the dust aerosol content retrieval can be stably, quickly and conveniently performed; and the influence of Martian surface contribution inaccuracy on atmospheric retrieval result precision is reduced.

Description

technical field [0001] The invention relates to the technical field of inversion of atmospheric components by satellite remote sensing, and relates to a fast inversion method for dust aerosol optical thickness. Background technique [0002] Dust aerosols are an important component of the Martian atmosphere. Dust aerosols are suspended in the atmosphere all year round and large-scale dust storms erupt almost every year. The distribution and properties of Martian dust aerosols are related to the cycle of water vapor and carbon dioxide on Mars. Understanding the cycle and properties of dust aerosols will help to explore the Martian atmosphere. [0003] Mars Express (MEX) is currently the Mars orbiter with the longest continuous observation time. Its planetary Fourier spectrometer (PFS) data has the inversion capability of various atmospheric components. important data on the interaction. [0004] The current physical inversion method for monitoring dust aerosols on Mars uses ...

AI Technical Summary

Problems solved by technology

[0005] MEX-PFS data cannot be used to invert the surface emissivity due to the problem of signal-to-noise ratio, and many inversion algorithms assume that the surface emissivity is uniform; in addition, the surface temperature is calculated by its brightness temperature when inverting MEX-PFS data, which cannot be accurate The representative surface temperature of Mars, this uncertain assumption of the Martian surface will introduce errors in the atmospheric inversion

[0006] Another problem in physical inversion is the huge amount of data calculation. The hyperspectral characteristics of MEX-PFS make the inversion spectrum huge. In addition, the atmospheric model requires a huge amount of calculation when calculating the scattering effect of aerosols.

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