On the altitudinal level dependence of aerosol volume scattering coefficient in the Saturn’s atmosphere. I. Integral disk
Ovsak, OS |
Kinemat. fiz. nebesnyh tel (Online) 2021, 37(3):46-57 |
https://doi.org/10.15407/kfnt2021.03.046 |
Start Page: Dynamics and Physics of Solar System Bodies |
Language: Ukrainian |
Abstract: Modern state of researches on the vertical structure, composition and microphysical parameters of aerosol component in the atmosphere of Saturn is considered. The disadvantages of applying the methods of model analysis of the giant planet atmospheres with the compulsory assignment of the number and parameters of aerosol layers artificially included in the model of the vertical structure of the atmosphere are noted. The advantages of the effective optical depth method using are listed. This method makes it possible to determine a qualitative picture of the altitudinal distribution of cloud cover in the giant planet atmospheres, and also to calculate a number of microphysical parameters of their aerosol component without preliminary designation of a model vertical structure. The reflectivity measurements data of Saturn integral disk in the spectral absorption bands of methane at 619, 727, 842, 864, and 887 nm are in use. The aerosol volumetric scattering coefficient dependence on the pressure in the upper atmosphere is calculated. The method of effective optical depth was applied. Model assumptions, quantitative ratios of the main atmospheric gases, and parameters of the size distribution function of aerosol particles are listed. On the studied altitude levels of Saturn's atmosphere, the continuous presence of aerosols with varying scattering properties was found. The altitude levels with the highest aerosols thickening have been determined. The most powerful in the planet's atmosphere cloud system has two maxima of the volume scattering coefficient at levels of about and 430 mbar and an intermediate peak of about 1.0 bar. In the pressure range 2.2...8.0 bar, there is an extended aerosol layer with a scattering maximum determined in the pressure range of 3.8—4.8 bar, depending on the analyzed methane absorption band. The revealed significant dispersion differences in the combined dependence of the volumetric aerosol scattering coefficient indicate a probable change in the radius and / or nature of aerosol particles in the deep levels of Saturn's atmosphere. |
Keywords: atmospheric aerosol, maximum scattering levels, Saturn, vertical structure |
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