We wish to thank Jess Charba of NOAA/Techniques Development Laboratory for the precipitation data and the NCEP–NCAR reanalysis team for the reanalysis data. Special thanks go to John Janowiak and Kingtse Mo for thorough reviews of an early version of this manuscript, and to Muthuvel Chelliah for Fig. 4. The authors are also indebted to Hugo Berbery, Vernon Kousky, Gene Rasmusson, Chester Ropelewski, and Jae Schemm for insightful discussions. This work was partially supported by the NOAA Office of Global Programs under the Pan American Climate Studies project, by the GEWEX Continental-Scale International Project, and by Interagency Agreement S-41376-F under the authority of NASA/GSFC.
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