Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data - INSU - Institut national des sciences de l'Univers Access content directly
Journal Articles Geophysical Research Letters Year : 2007

Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data

Abstract

We make use of microwave measurements of the tropical free tropospheric relative humidity (FTH) to evaluate the extent to which the water vapor distribution in four general circulation models is faithful to reality. The comparison is performed in the tropics by sorting the FTH in dynamical regimes defined upon the 500 hPa vertical velocity. Because microwave radiation penetrates non‐rainy and warm clouds, we are able to estimate the FTH over most of the dynamical regimes that characterize the tropics. The comparisons reveal that two models simulate a free troposphere drier than observed (<10%), while the others agree with the observations. Despite some differences, the level of agreement is good enough to lend confidence in the representation of atmospheric moistening processes. A climate change scenario, tested on two models, shows a tendency to maintain the FTH to an almost fixed value be it an ascending or a subsiding regime.
Fichier principal
Vignette du fichier
ark _67375_WNG-BW07XL2R-4.pdf (291 Ko) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

insu-02153945 , version 1 (05-03-2021)

Identifiers

Cite

Hélène Brogniez, Raymond T. Pierrehumbert. Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data. Geophysical Research Letters, 2007, 34 (17), ⟨10.1029/2006GL029118⟩. ⟨insu-02153945⟩
45 View
33 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More