Hemispherical distribution of CO above the Venus' clouds by ground-based 2.3μm spectroscopy

N. Iwagami, T. Yamaji, S. Ohtsuki, Joji Hashimoto

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8 Citations (Scopus)


The abundance of carbon monoxide in the Venus' dayside atmosphere above the clouds was measured by ground-based 2.3μm spectroscopy for 4days. The hemispherical distributions found show no significant latitudinal or longitudinal structure. The disc-averaged mixing ratio of 58±17ppm found at a representative height of 62-67km is consistent with previous measurements. Such a flat distribution of CO abundance above the clouds seems to be controlled by an efficient horizontal eddy diffusion with a time scale of 30days or shorter although the CO distribution below the clouds seems to be controlled by the meridional circulation. The pole-ward wind speed of the meridional circulation above the clouds is estimated to be 0.2ms-1 or less based on the difference between the CO mixing ratios above and below the clouds.

Original languageEnglish
Pages (from-to)558-563
Number of pages6
Issue number2
Publication statusPublished - Jun 2010



  • Spectroscopy
  • Venus, Atmosphere

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

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