lmd_EMC31989_abstracts.html

1989 .

(2 publications)

R. D. Cess, G. L. Potter, J. P. Blanchet, G. J. Boer, S. J. Ghan, J. T. Kiehl, H. Le Treut, Z.-X. Li, X.-Z. Liang, J. F. B. Mitchell, J.-J. Morcrette, D. A. Randall, M. R. Riches, E. Roeckner, U. Schlese, A. Slingo, K. E. Taylor, W. M. Washington, R. T. Wetherald, and I. Yagai. Interpretation of Cloud-Climate Feedback as Produced by 14 Atmospheric General Circulation Models. Science, 245:513-516, August 1989. [ bib | DOI | ADS link ]

Understanding the cause of differences among general circulation model projections of carbon dioxide-induced climatic change is a necessary step toward improving the models. An intercomparison of 14 atmospheric general circulation models, for which sea surface temperature perturbations were used as a surrogate climate change, showed that there was a roughly threefold variation in global climate sensitivity. Most of this variation is attributable to differences in the models' depictions of cloud-climate feedback, a result that emphasizes the need for improvements in the treatment of clouds in these models if they are ultimately to be used as climatic predictors.

M. Desbois, S. Guessous, and L. Picon. Observation of mean dynamic fields from Meteosat large scale water vapor structure motions. Advances in Space Research, 9:83-90, 1989. [ bib | DOI | ADS link ]

With the objective characterizing atmospheric dynamics for particular months, structures appearing at large scales on Meteosat water vapor images are tracked with similar methods as those used for cloud tracking in other channels at smaller scales. For this purpose sampled ISCCP images at resolution 30 km with time intervals of 3 hours are used. Mean monthly “motion fields” are computed. These fields are very consistent with the general circulation of the upper troposphere. They are shown to represent the motions of synoptic systems rather than the wind at a particular level. Nevertheless, significant interannual variations of the large scale circulations can be observed.