Characteristics of particle dispersion in the North Atlantic: An alternative interpretation of SOFAR float results

• Published in: Deep Sea Research Part A. Oceanographic Research Papers
• Main Author: Böning, Claus W.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Pergamon Press 1988
• Subjects: North Atlantic
• Online Access: https://oceanrep.geomar.de/id/eprint/3016/; https://oceanrep.geomar.de/id/eprint/3016/1/1-s2.0-0198014988900891-main.pdf; https://doi.org/10.1016/0198-0149(88)90089-1

An analysis of published results on the dispersion behavior of SOFAR floats indicates a systematic depth dependence of the mixing length in the North Atlantic subtropical gyre. In contrast to the integral time scale, the length scale appears to be independent of eddy intensity in the thermocline (Lx, Ly ∼ 80, 45 km) and in the deep ocean (Lx ∼ Ly : 20 – 30 km). A similar decrease with depth is revealed by particle dispersion in an eddy-resolving circulation model and interpreted as an enhanced effect of wave behavior in the weaker, subthermocline flow. The only weak anisotropy of deep float dispersion suggests an influence of bottom roughness on the structure of eddy variability.