The authors are grateful to Professor A. Arakawa for discussions on model behavior, and to two anonymous reviewers for comments on the text. The authors also thank Professor D. Randall for his comments on an earlier report of this study. The coupled GCM simulation was conducted by Dr. C.-C. Ma. This work was supported by NASA under Grant NAG5-2224, NOAA/GOALS under Grant NA66GP0121, and the University of California under the CLC Project. Model integrations were performed at the San Diego Supercomputer Center and the National Center for Atmospheric Research Climate Simulation Laboratory. The authors wish to thank I. Grecu and J. Westfall for their help in the preparation of this manuscript.
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