We are grateful to E. Kalnay and S. Nigam of UMD for valuable suggestions. The authors appreciate the support provided by the National Science Foundation (Grants OCE9530220 and OCE9812404). QuikScat wind has been obtained from the NASA–NOAA-sponsored data system Seaflux, at JPL through the courtesy of W. Timothy Liu and W. Tang. A. Dessier kindly provided the sea surface salinity observations. The suggestions given by anonymous reviewers were helpful and stimulating. The gridded TRMM rainfall data are available online at http://tsdis.gsfc.nasa.gov/trmmopen/3G68.html. SSM/I wind velocities were kindly provided by R. Atlas and J. Ardizzone. The European Research Satellite-1/2 mean wind field atlas is available online at http://www.ifremer.fr/cersat. SSM/I precipitation and water content data are produced by Remote Sensing Systems and sponsored, in part, by NASA's Earth Science Information Partnerships (ESIP): A federation of information sites for earth science; and by the NOAA–NASA Pathfinder Program for early EOS products; principal investigator: Frank Wentz.
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