We thank Gene Rasmusson for his many helpful comments and suggestions during the evolution of this work. This work also benefitted through useful and productive interactions with Tim Barnett, Phil Jones, Gabi Hegerl, Ben Santer, and Mike Fiorino. We also wish to thank John Christy for providing the MSU2 data and for providing comments and suggestions during the course of this work and the Climatic Research Unit at the University of East Anglia for providing the surface temperature datasets. Critical comments by the two anonymous reviewers of the Journal of Climate greatly improved the readability and tied several loose ends of this manuscript. Comments by Tom Smith and Vern Kousky on earlier drafts of this paper are greatly appreciated. This work was partially supported by a grant from the Climate Change Data and Detection Program at NOAA’s Office of Global Programs.
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