Antarctic Circumpolar Current impacts on internal wave life cycles

Major gaps exist in our understanding of the pathways between internal wave generation and breaking in the Southern Ocean, with important implications for the distribution of internal wave‐driven mixing, the sensitivity of ocean mixing rates and patterns to changes in the ocean environment, and the...

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Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Waterman, S, Meyer, A, Polzin, KL, Naveira Garabato, AC, Sheen, KL
Format: Article in Journal/Newspaper
Language:English
Published: Amer Geophysical Union 2021
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Online Access:https://doi.org/10.1029/2020GL089471
http://ecite.utas.edu.au/144212
Description
Summary:Major gaps exist in our understanding of the pathways between internal wave generation and breaking in the Southern Ocean, with important implications for the distribution of internal wave‐driven mixing, the sensitivity of ocean mixing rates and patterns to changes in the ocean environment, and the necessary ingredients of mixing parameterizations. Here we assess the dominant processes in internal wave evolution by characterizing wave and mesoscale flow scales based on full‐depth in situ measurements in a Southern Ocean mixing hot spot and a ray tracing calculation. The exercise highlights the importance of Antarctic Circumpolar Current jets as a dominant influence on internal wave life cycles through advection, the modification of wave characteristics via wave‐mean flow interactions, and the set‐up of critical layers for both upward‐ and downward‐propagating waves. Our findings suggest that it is important to represent mesoscale flow impacts in parameterizations of internal wave‐driven mixing in the Southern Ocean.