The authors appreciate beneficial conversations with F. Selten, R. Saravanan, J. von Storch, J. Tribbia, A. Hense, P. Sardeshmukh, C. Tebaldi, and D. Nychka. Especially useful has been correspondence with T. DelSole, who pointed out the relevance of his paper [DelSole (2000)] to the question of Δt dependence of LIM operators and who clarified remarks made in that paper. A. Mai formatted the AGCM data and produced some of our figures. This study was partially funded by NOAA Grant NA17GP1376 and NASA Grant S-44809-G. The support of the second author by NCAR’s Advanced Study Program is also gratefully acknowledged.
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