I have benefited from many insightful discussions with Weiqing Han of the University of Colorado. Her work provided a source of extensive references for this study. Ichiro Fukumori, the leader of the JPL component of the ECCO Consortium, kindly provided the velocity products for the study. Akiko Hayashi of JPL has always been my valuable source of programming assistance. I also benefited from discussions with Claire Perigaud, Tong Lee, and Duane Waliser of JPL. The research presented in the paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautic and Space Administration. Support from the TOPEX/Poseidon, Jason, and OSTM projects is acknowledged.
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