It would have been impossible to perform vital parts of this study without the river discharge data provided by the USGS. Thanks also to Mark Govett, FSL/NOAA, for his help with unpacking the radiosonde data; Wayne Higgins, CPC/NCEP, for help with the precipitation data and useful comments; Hugo Berbery, University of Maryland, for his discussion of the paper; Chris Milly, USGS and GFDL, and Bill Kirby, USGS, for their insightful suggestions; and to Gene Peck, Hydex Inc., and Pavel Groisman, NCDC, for discussions regarding winter precipitation estimates. A special thanks to Gene Rasmusson, University of Maryland, for his useful comments and encouragement during the course of the study. Finally, we thank John Roads and an anonymous reviewer for their helpful comments and suggestions. This work was partially supported by the NOAA Office of Global Programs under the GEWEX Continental-Scale International Project (GCIP).
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