We wish to thank Jess Charba for the precipitation data and Mark Govett for help with unpacking the radiosonde data. The authors are indebted to Drs. Gerry Bell, Jae-Kyung Schemm, Mark Helfand, and Siegfried Schubert for insightful discussions and to two anonymous reviewers who helped to substantially improve the manuscript. Thanks also go to Chung-Yu Wu and Yehui Chang for help in preparing the DAO reanalysis data and to Wesley Ebisuzaki and Muthu Chelliah for help in preparing the NCEP reanalysis data. This work was partially supported by Interagency Agreement S-41367-F under the authority of NASA/GSFC and by the NOAA Office of Global Programs under the GEWEX Continental-Scale International Project (GCIP).
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