We are grateful to Russ Davis for making Southern Ocean ALACE floats available and to Peter Niiler and Sharon Lukas for providing surface drifter data. NCEP reanalysis data was provided by the NOAA–CIRES Climate Diagnostics Center, Boulder, Colorado, from their Web site at http://www.cdc.noaa.gov/. This research was funded by NSF Award OCE-9985203/OCE-0049066.
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