The authors wish to thank the captains and crews of the R/V Endeavor, R/V Oceanus, and R/V Weatherbird II for their help in the deployment of the sound sources and collection of the observations. J. Valdes, B. Guest, and R. Tavares of the WHOI Float Operations Group are also gratefully acknowledged for their patience and skill in the preparation of the instruments. M. Mensel, then of IFREMER, kindly provided us with his float data processing software and answered many questions. A sound source deployed by K. Leaman of the University of Miami was useful in extending the tracking range of the floats. R. Pickart and D. Torres kindly provided hydrographic data from the BOUNCE cruises. R. Curry provided valuable guidance in the use of the HydroBase climatology. Helpful discussions with R. Pickart, M. Spall, N. Hogg, and W. Smethie contributed to the development of the ideas presented in this paper. The work was supported under Grant OCE93-01448 from the National Science Foundation to the Woods Hole Oceanographic Institution.
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