Correlations between cloud thickness and sub-cloud water abundance on Venus

Past spacecraft observations of Venus have found considerable spatial and temporal variations of water vapour abundance above the clouds. Previous searches for variability below the clouds at 30–45 km altitude found no large scale latitudinal gradients, but lacked the spatial resolution to detect sm...

Full description

Bibliographic Details
Main Authors: Tsang, C, Wilson, C, Barstow, J, Irwin, P, Taylor, F, McGouldrick, K, Piccioni, G, Drossart, P, Svedhem, H
Format: Journal article
Language:English
Published: American Geophysical Union 2010
Subjects:
_version_ 1797075563377065984
author Tsang, C
Wilson, C
Barstow, J
Irwin, P
Taylor, F
McGouldrick, K
Piccioni, G
Drossart, P
Svedhem, H
author_facet Tsang, C
Wilson, C
Barstow, J
Irwin, P
Taylor, F
McGouldrick, K
Piccioni, G
Drossart, P
Svedhem, H
author_sort Tsang, C
collection OXFORD
description Past spacecraft observations of Venus have found considerable spatial and temporal variations of water vapour abundance above the clouds. Previous searches for variability below the clouds at 30–45 km altitude found no large scale latitudinal gradients, but lacked the spatial resolution to detect smaller scale variations. Here we interpret results from the VIRTIS imaging spectrometer on Venus Express, remotely sounding at near-infrared ‘spectral window’ wavelengths, as indicating that the water vapour abundance at 30–40 km altitude varies from 22 to 35 ppmv (±4 ppmv). Furthermore, this variability is correlated with cloud opacity, supporting the hypothesis that its genesis is linked to cloud convection. It is also possible to fit the observations without requiring spatial variation of water abundance, but this places a strong constraint on the spectral dependence of the refractive index data assumed for the lower cloud particles, for which there is as yet no supporting evidence.
first_indexed 2024-03-06T23:52:05Z
format Journal article
id oxford-uuid:72f20bda-b4d3-4106-a9fd-c26594a5836e
institution University of Oxford
language English
last_indexed 2024-03-06T23:52:05Z
publishDate 2010
publisher American Geophysical Union
record_format dspace
spelling oxford-uuid:72f20bda-b4d3-4106-a9fd-c26594a5836e2022-03-26T19:53:21ZCorrelations between cloud thickness and sub-cloud water abundance on VenusJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:72f20bda-b4d3-4106-a9fd-c26594a5836ePhysicsAtmospheric, Oceanic, and Planetary physicsEnglishSymplectic Elements at OxfordAmerican Geophysical Union2010Tsang, CWilson, CBarstow, JIrwin, PTaylor, FMcGouldrick, KPiccioni, GDrossart, PSvedhem, HPast spacecraft observations of Venus have found considerable spatial and temporal variations of water vapour abundance above the clouds. Previous searches for variability below the clouds at 30–45 km altitude found no large scale latitudinal gradients, but lacked the spatial resolution to detect smaller scale variations. Here we interpret results from the VIRTIS imaging spectrometer on Venus Express, remotely sounding at near-infrared ‘spectral window’ wavelengths, as indicating that the water vapour abundance at 30–40 km altitude varies from 22 to 35 ppmv (±4 ppmv). Furthermore, this variability is correlated with cloud opacity, supporting the hypothesis that its genesis is linked to cloud convection. It is also possible to fit the observations without requiring spatial variation of water abundance, but this places a strong constraint on the spectral dependence of the refractive index data assumed for the lower cloud particles, for which there is as yet no supporting evidence.
spellingShingle Physics
Atmospheric, Oceanic, and Planetary physics
Tsang, C
Wilson, C
Barstow, J
Irwin, P
Taylor, F
McGouldrick, K
Piccioni, G
Drossart, P
Svedhem, H
Correlations between cloud thickness and sub-cloud water abundance on Venus
title Correlations between cloud thickness and sub-cloud water abundance on Venus
title_full Correlations between cloud thickness and sub-cloud water abundance on Venus
title_fullStr Correlations between cloud thickness and sub-cloud water abundance on Venus
title_full_unstemmed Correlations between cloud thickness and sub-cloud water abundance on Venus
title_short Correlations between cloud thickness and sub-cloud water abundance on Venus
title_sort correlations between cloud thickness and sub cloud water abundance on venus
topic Physics
Atmospheric, Oceanic, and Planetary physics
work_keys_str_mv AT tsangc correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus
AT wilsonc correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus
AT barstowj correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus
AT irwinp correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus
AT taylorf correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus
AT mcgouldrickk correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus
AT piccionig correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus
AT drossartp correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus
AT svedhemh correlationsbetweencloudthicknessandsubcloudwaterabundanceonvenus