We are especially thankful to Isaac Held for his comments and suggestions. We are also grateful for valuable discussions with Alan Plumb, Lorenzo Polvani, Walter Robinson, Edwin Gerber, and Michael Ring. We thank three anomalous reviewers for helpful comments, and Bruce Wyman and S. J. Lin for integrating the GCM experiments. The lead author is supported by a NOAA Climate and Global Change Postdoctoral Fellowship, administered by the University Corporation for Atmospheric Research, and most of the work was done when he was a graduate student at Princeton University, supported by Award NA17RJ2612 from the National Oceanic and Atmospheric Administration, U.S. Department of Commerce. PZG is supported by the Ramon y Cajal program of the Ministerio de Educación y Ciencia of Spain and by a Universidad Complutense-Flores Valles fellowship.
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