We acknowledge the international modeling groups for providing their data for analysis, the Program for Climate Model Diagnosis and Intercomparison (PCMDI) for collecting and archiving the model data, the JSC/CLIVAR Working Group on Coupled Modelling (WGCM) and their Coupled Model Intercomparison Project (CMIP) and Climate Simulation Panel for organizing the model data analysis activity, and the IPCC WG1 TSU for technical support. The IPCC Data Archive at Lawrence Livermore National Laboratory is supported by the Office of Science, US Department of Energy. Funding for AC was provided by NOAA through the U.S. CLIVAR Droughts in Coupled Models Project (DRICOMP) and through CDEP funding to ESRL. Insightful conversations with Clara Deser, as well as constructive criticism and suggestions from the NOAA/ESRL/PSD Attribution Group, in particular Martin Hoerling, Judith Perlwitz, Klaus Wolter, and Dezheng Sun, are gratefully acknowledged.
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