This work was partially supported jointly by NOAA’s Office of Global Program’s and the Department of Energy’s Climate Change Data and Detection Program Element, NSF Grant ATM93-14495, and the Scripps Institute of Oceanography. We are grateful to Curt Covey and the CMIP Program for providing us with the model data used in this study. Thanks are due to G. Hegerl for useful discussions on the project. We also gratefully acknowledge the use of the global air temperature dataset from the Climate Research Unit (courtesy of Phil Jones) and use of version 2.2 of the Global Sea-Ice and Sea Surface Temperature dataset, 1903–1994 by N. A. Rayner, E. B. Horton, D. E. Parker, C. K. Folland, and R. B. Hackett of the Hadley Centre for Climate Prediction and Research Meteorological Office, London Road, Bracknell, Berkshire, United Kingdom.
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