The authors thank C. S. Cox for suggesting the circulation model approach, for many valuable discussions, and for the inspiration of his example over the years. We also thank A. D. Chave, B. D. Cornuelle, E. Gottlieb, D. S. Luther, T. Rossby, T. B. Sanford, V. Shneyer, and G. Spence for useful discussions; F. Bryan for providing the depth-integrated WOCE Community Modeling Effort results; and A. Manke and D. McClurg for programming support. A. D. Chave and an anonymous reviewer are thanked for comments that have greatly improved the paper. We are indebted to NSF Grant OC90-19314, the National Research Council, and NOAA’s Atlantic Climate Program for supporting this work.
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