Tom Knutson, Gabriel Vecchi, Ron Stouffer, Steve Klein, Tony Gordon, and three anonymous reviewers provided insightful comments that greatly improved this paper. The authors thank the providers of all of the observational datasets listed in Table 1. We also thank the members of GFDL Modeling Services for their assistance with model infrastructure support and data processing. Wavelet analyses were produced using Fortran codes provided by C. Torrence and G. Compo at http://paos.colorado.edu/research/wavelets.
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