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dc.contributor.authorDrake, Henri F
dc.contributor.authorRuan, Xiaozhou
dc.contributor.authorCallies, Jörn
dc.contributor.authorOgden, Kelly
dc.contributor.authorThurnherr, Andreas M
dc.contributor.authorFerrari, Raffaele
dc.date.accessioned2023-02-15T15:09:56Z
dc.date.available2023-02-15T15:09:56Z
dc.date.issued2022
dc.identifier.urihttps://hdl.handle.net/1721.1/148074
dc.description.abstract<jats:title>Abstract</jats:title> <jats:p>ABSTRACT: The abyssal overturning circulation is thought to be primarily driven by small-scale turbulent mixing. Diagnosed watermass transformations are dominated by rough topography “hotspots”, where the bottom-enhancement of mixing causes the diffusive buoyancy flux to diverge, driving widespread downwelling in the interior—only to be overwhelmed by an even stronger up-welling in a thin Bottom Boundary Layer (BBL). These watermass transformations are significantly underestimated by one-dimensional (1D) sloping boundary layer solutions, suggesting the importance of three-dimensional physics. Here, we use a hierarchy of models to generalize this 1D boundary layer approach to three-dimensional eddying flows over realistically rough topography. When applied to the Mid-Atlantic Ridge in the Brazil Basin, the idealized simulation results are roughly consistent with available observations. Integral buoyancy budgets isolate the physical processes that contribute to realistically strong BBL upwelling. The downwards diffusion of buoyancy is primarily balanced by upwelling along the sloping canyon sidewalls and the surrounding abyssal hills. These flows are strengthened by the restratifying effects of submesoscale baroclinic eddies and by the blocking of along-ridge thermal wind within the canyon. Major topographic sills block along-thalweg flows from restratifying the canyon trough, resulting in the continual erosion of the trough’s stratification. We propose simple modifications to the 1D boundary layer model which approximate each of these three-dimensional effects. These results provide <jats:italic>local</jats:italic> dynamical insights into mixing-driven abyssal overturning, but a complete theory will also require the <jats:italic>non-local</jats:italic> coupling to the basin-scale circulation.</jats:p>en_US
dc.language.isoen
dc.publisherAmerican Meteorological Societyen_US
dc.relation.isversionof10.1175/JPO-D-22-0009.1en_US
dc.rightsArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.en_US
dc.sourceAmerican Meteorological Society (AMS)en_US
dc.titleDynamics of eddying abyssal mixing layers over sloping rough topographyen_US
dc.typeArticleen_US
dc.identifier.citationDrake, Henri F, Ruan, Xiaozhou, Callies, Jörn, Ogden, Kelly, Thurnherr, Andreas M et al. 2022. "Dynamics of eddying abyssal mixing layers over sloping rough topography." Journal of Physical Oceanography.
dc.contributor.departmentMassachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciencesen_US
dc.relation.journalJournal of Physical Oceanographyen_US
dc.eprint.versionFinal published versionen_US
dc.type.urihttp://purl.org/eprint/type/JournalArticleen_US
eprint.statushttp://purl.org/eprint/status/PeerRevieweden_US
dc.date.updated2023-02-15T14:53:43Z
dspace.orderedauthorsDrake, HF; Ruan, X; Callies, J; Ogden, K; Thurnherr, AM; Ferrari, Ren_US
dspace.date.submission2023-02-15T14:53:46Z
mit.licensePUBLISHER_POLICY
mit.metadata.statusAuthority Work and Publication Information Neededen_US


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