Study on Influencing Factors of the Information Content of Satellite Remote-Sensing Aerosol Vertical Profiles Using Oxygen A-Band

• Published in: Remote sensing (Basel, Switzerland) Vol. 15; no. 4; p. 948
• Main Authors: Wang, Yuxuan, Sun, Xiaobing, Huang, Honglian, Ti, Rufang, Liu, Xiao, Fan, Yizhe
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.02.2023
• Subjects: absorption; Accuracy; aerosol vertical profiles; Aerosols; Algorithms; Artificial satellites in remote sensing; Atmosphere; climate; Comparative analysis; Data processing; Distribution; geometry; information content analysis; Measurement; Meteorological satellites; Oxygen; oxygen absorption band; Radiation; Radiative transfer; Remote sensing; Retrieval; Satellite observation; satellite remote sensing; Satellites; Scattering angle; Signal to noise ratio; Size distribution; spatial distribution; spectral analysis; Spectral resolution; Stratosphere; Vertical distribution; China
• ISSN: 2072-4292; 2072-4292
• DOI: 10.3390/rs15040948

Aerosol vertical distribution is decisive and hard to be constrained. It is of great significance for the study of atmospheric climate and environment. Oxygen absorption A-bands (755–775 nm) provide a unique opportunity to acquire vertical aerosol profiles from satellites over a large spatial coverage. To investigate the ability of O2 A-bands in retrieving aerosol vertical distribution, the dependence of retrieval on satellite observation geometry, spectral resolution, signal-to-noise ratio (SNR), size distribution, and a priori knowledge is quantified using information content theory. This work uses the radiative transfer model UNL to simulate four aerosol modes and the instrument noise model. The simulations show that a small scattering angle leads to an increase in the total amount of observed aerosol profile information, with the degrees freedom of signal (DFS) of a single band increasing from 0.4 to 0.85 at high spectral resolution (0.01 nm). The total DFS value of O2 A-bands varies accordingly between 1.2–2.3 to 3.8–5.1 when the spectral resolution increases from 1 nm to 0.01 nm. The spectral resolution has a greater impact on DFS value than the impact from SNR (an improvement of roughly 41–53% resulted from the change in spectral resolution and the SNR led to 13–18%). The retrieval is more sensitive to aerosols with a coarse-dominated mode. The improvement in spectral resolution on information acquisition is demonstrated using the DFS and the posterior error at various previous errors and resolutions.