Evidence for slow mixing across the pycnocline from an open-ocean tracer-release experiment

@article{Ledwell1993EvidenceFS,
  title={Evidence for slow mixing across the pycnocline from an open-ocean tracer-release experiment},
  author={James R. Ledwell and Andrew J. Watson and Cliff S. Law},
  journal={Nature},
  year={1993},
  volume={364},
  pages={701-703}
}
THE distributions of heat, salt and trace substances in the ocean thermocline depend on mixing along and across surfaces of equal density (isopycnal and diapycnal mixing, respectively). Measurements of the invasion of anthropogenic tracers, such as bomb tritium and 3He (see, for example, refs 1 and 2), have indicated that isopycnal processes dominate diapycnal mixing, and turbulence measurements have suggested that diapycnal mixing is small3,4, but it has not been possible to measure accurately… 
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