1. U.S. Geological Survey, 3215 Marine Street, Boulder, Colorado 80303, United States
2. John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
3. U.S. Geological Survey, 4200 New Haven Road, Columbia, Missouri 65201, United States
4. Graduate School of Oceanography, University of Rhode Island, Horn Building 118, 215 South Ferry Road, Narragansett, Rhode Island 02882, United States
5. U.S. Geological Survey, 10 Bearfoot Road, Northborough, Massachusetts 01532, United States
6. University of Colorado Denver, P.O. Box 173364, Denver, Colorado 80217, United States