Absorption of sunlight in the atmosphere of Venus

Research output: Contribution to journalArticle

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Abstract

In this report the fluxes measured by the solar flux radiometer (LSFR) of the Pioneer Venus large probe are compared with calculations for model atmospheres. If the large particles of the middle and lower clouds are assumed to be sulfur, strong, short-wavelength absorption results in a net flux profile significantly different from the LSFR net flux measurements. Models in which the smallest particles are assumed to be sulfur gave flux profiles consistent with the measurements if an additional source of absorption is included in the upper cloud. The narrowband data from 0.590 to 0.665 micrometer indicate an absorption optical depth of about 0.05 below the cloud bottom. The broadband data imply that either this absorption extends over a considerable wavelength interval (as might be the case for dust) or that a very strong absorption band lies on one side of the narrowband filter (as suggested by early Venera II and Venera 12 reports). Thermal balance calculations based on the measured visible fluxes indicate high surface temperature for reasonable assumptions of cloud opacity and water vapor abundance. The lapse rate becomes convective within the middle cloud. For water mixing ratios of 2.0 × 10-4 below the clouds we find a subadiabatic region extending from the cloud bottom to altitudes near 35 kilometers.

Original languageEnglish (US)
Pages (from-to)80-82
Number of pages3
JournalScience
Volume205
Issue number4401
StatePublished - 1979

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Venus
atmosphere
sulfur
broadband data
wavelength
flux measurement
mixing ratio
radiometer
optical depth
water vapor
surface temperature
probe
dust
filter

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  • General

Cite this

Absorption of sunlight in the atmosphere of Venus. / Tomasko, Martin G; Doose, Lyn R.; Smith, Peter.

In: Science, Vol. 205, No. 4401, 1979, p. 80-82.

Research output: Contribution to journalArticle

Tomasko, MG, Doose, LR & Smith, P 1979, 'Absorption of sunlight in the atmosphere of Venus', Science, vol. 205, no. 4401, pp. 80-82.
Tomasko, Martin G ; Doose, Lyn R. ; Smith, Peter. / Absorption of sunlight in the atmosphere of Venus. In: Science. 1979 ; Vol. 205, No. 4401. pp. 80-82.
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