The authors are grateful to Greg Hakim and two anonymous reviewers for their comments, which helped improve the manuscript. Sharanya Majumdar and Kathryn Sellwood gratefully acknowledge funding by NOAA THORPEX. Daniel Hodyss was sponsored by a postdoctoral fellowship at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science, and the Naval Research Laboratory and the Office of Naval Research under Program Element 0601153N. The authors are also grateful to the National Centers for Environmental Prediction for provision of the ensemble data and supercomputer time, and to Craig Bishop and Istvan Szunyogh for helpful discussions. Carolyn Reynolds and Justin McLay of the Naval Research Laboratory, Monterey, California, provided the NAVDAS estimates of analysis error variance.
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