We thank Karl Taylor, Piers Forster, Glen Harris, Rowan Sutton, Buwen Dong, Jeff Kiehl, and Hugo Lambert for useful discussions, William Ingram and Jason Lowe for careful comments, which helped to improve the clarity and precision of the manuscript, and the referees for their positive and helpful reviews. Work at the Hadley Centre was supported by the U.K. Department for Environment, Food and Rural Affairs under Contract PECD 7/12/37 and by the Government Meteorological Research and Development Programme. Work at the Walker Institute was supported by the Climate Programme of the National Centre for Atmospheric Science (NCAS). We acknowledge the modeling groups for making their simulations available for analysis, the Program for Climate Model Diagnosis and Intercomparison (PCMDI) for collecting and archiving the CMIP3 and CFMIP model output, and the WCRP’s Working Group on Coupled Modelling (WGCM) for organizing the model data analysis activity. The WCRP CMIP3 and CFMIP multimodel datasets are supported by the Office of Science, U.S. Department of Energy.
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