Stimulating comments from Michael Tippett and Huug Van den Dool lead to significant improvements in the model selection and assessment methodologies employed in this paper. Jennifer Adams provided helpful assistance on the figures. Comments from David Stephenson and the reviewers also lead to improvements on the presentation. We gratefully acknowledge the multimodel ensemble hindcast dataset provided freely and conveniently by the DEMETER project. The particular surface temperature dataset used in this study was provided by Kyung Emilia Jin. This research was supported by the National Science Foundation (ATM0332910), National Aeronautics and Space Administration (NNG04GG46G), and the National Oceanographic and Atmospheric Administration (NA04OAR4310034).
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