The authors offer their gratitude for support through the Office of Science (BER), U.S. Department of Energy, Grant DE-FG02-05ER64058, through the National Science Foundation, Grants ATM-0649512 and OPP-0230325, and through the Arctic Science Program, Grant ARC-0520496. In addition, we thank Drs. Johannes Verlinde, Eugene Clothiaux, and Jerry Harrington for their helpful comments. We also thank the Climate Analysis Branch of the NOAA Earth System Research Laboratory/Physical Sciences Division for providing us with the NCEP–NCAR reanalysis data. Finally, we offer thanks to two anonymous reviewers for their helpful comments that strengthened this manuscript.
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