The first author expresses his thanks to Tony Hollingsworth, Martin Miller, and Anton Beljaars, who made possible a visit to the ECMWF of 8 months by the first author. The first author hopes that ECMWF has benefited as much as the first author has from this visit. Assistance in performing the model experiments provided by Nils Wedi and David Dent of ECMWF is kindly acknowledged. Mark Crane of GFDL kindly supplied his plotting programs and data from the LC95 and LC97 studies. Comments on the manuscript by Anton Beljaars, Ngar-Cheung Lau, Martin Miller, and Brian Soden are appreciated. The speed with which the anonymous reviewers returned their comments to the editor is greatly appreciated.
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