Chris Wilson is grateful for support from the University of Liverpool and the Proudman Oceanography Laboratory. This study also received support from NERC RAPID Grant NER/T/S/2002/00439. The authors thank two anonymous reviewers for their insightful comments, as well as N. Maximenko and P. P. Niiler for the use of their mean dynamic height dataset. The altimeter products were produced by the CLS Space Oceanography Division (EVK2-CT2001-00117) and with support from CNES; the ERA-40 products were obtained from ECMWF; and the AVHRR Oceans Pathfinder SST data were obtained from the NASA Jet Propulsion Laboratory, Pasadena, CA (more information is available online at http://podaac.jpl.nasa.gov).
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