Effect of meridional circulation on the Venusian cloud layer: A model study

T. Imamura, Joji Hashimoto

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The meridional circulation can have a large influence on the cloud formation on Venus. In our model, the observed depression of near-infrared optical thickness at mid-latitude is reproduced as a result of the enhancement of cloud thickness at low and high latitudes. At high latitudes, the poleward transport of H2SO4-H2O droplets in the upper atmosphere makes a thick cloud, since most of the H2SO4-H2O droplets photochemically produced are transported poleward by the meridional circulation. At low latitudes, the large-scale ascent of the concentrated H2SO4 vapor forms a dense lower cloud in accord with observations by entry probes. The equatorward transport of H2SO4 vapor below the cloud by the meridional circulation and the sedimentation of droplets in the lower cloud leads to the accumulation of H2SO4 vapor around the cloud base at low latitudes. The H2SO4 vapor distribution agrees with the radio occultation observations. The middle cloud can be caused by the condensation of H2SO4 vapor carried aloft by convective mixing.

Original languageEnglish
Pages (from-to)1569-1572
Number of pages4
JournalAdvances in Space Research
Volume23
Issue number9
Publication statusPublished - 1999
Externally publishedYes

Fingerprint

meridional circulation
Vapors
vapors
tropical regions
droplet
polar regions
radio occultation
Upper atmosphere
effect
ascent
Venus (planet)
upper atmosphere
Venus
Sedimentation
entry
optical thickness
condensation
Condensation
near infrared
probe

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Effect of meridional circulation on the Venusian cloud layer : A model study. / Imamura, T.; Hashimoto, Joji.

In: Advances in Space Research, Vol. 23, No. 9, 1999, p. 1569-1572.

Research output: Contribution to journalArticle

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