Brightness of day sky as a source of information on albedo of underlying surface in infrared region
V.E. Pavlov1, S.S. Orlov2, V.V. Pashnev2
1Institute for Water and Environmental Problems of the Siberian Branch of the RAS, 656038, Barnaul, 1, Molodezhnaya str. IWEP SB RAS
2Altai State University, 656015, Barnaul, 61, str. Lenina
Keywords: инфракрасная область спектра, оптические толщи рассеяния и поглощения, яркость неба, асимметрия аэрозольной индикатрисы рассеяния, infrared region, optical depth of scattering and absorption, sky brightness, asymmetry of aerosol scattering indicatrix
Abstract
In the first part of the paper, we offer a methodological ground for determination of the surface albedo in the near infrared (NIR) region using the observations of the atmosphere spectral transparency and the brightness of day cloudless sky in the Sun almucantar. The contribution of the component describing the processes of light reflection into the brightness at different angular distances from the Sun is analyzed. The effect of aerosol absorption on brightness components used to determine the albedo is estimated. The effect of the zenith angle of the Sun and the elongation of aerosol scattering indicatrix on the final albedo calculation is revealed.
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