The authors thank Phil Mote and two anonymous reviewers for their helpful comments, and Noah Knowles for providing data on the changing fraction of rain versus snow. Support was provided by the Lawrence Livermore National Laboratory through an LDRD grant to the Scripps Institution of Oceanography (SIO) via the San Diego Super Computer Center (SDSC) for the LUCSiD project. The MIROC simulations were supported by the Research Revolution 2002 of the Ministry of Education, Culture, Sports, Science and Technology of Japan. The PCM simulation had previously been made available to SIO by the National Center for Atmospheric Research for the ACPI project. The California Energy Commission provided partial salary support for DP and HH at SIO. The Department of Energy and NOAA supported TPB as part of the International Detection and Attribution Group (IDAG). The LLNL participants were supported by DOE-W-7405-ENG-48 funds to the Program of Climate Model Diagnosis and Intercomparison (PCMDI). The USGS and SIO provided partial salary support DC and MD at SIO.
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