On material transport by shelfbreak eddies
Citable URI
https://hdl.handle.net/1912/23788As published
https://doi.org/10.1175/JPO-D-18-0166.1DOI
10.1175/JPO-D-18-0166.1Keyword
Dispersion; Eddies; Frontogenesis/frontolysis; Instability; Lagrangian circulation/transport; JetsAbstract
The Lagrangian motion in the eddy field produced from an unstable retrograde jet along the shelf break is studied from idealized numerical experiments with a primitive equation model. The jet is initially in thermal wind balance with a cross-isobath density gradient and is not subjected to any atmospheric forcing. Over the course of the model integration, the jet becomes unstable and produces a quasi-stationary eddy field over a 2-month period. During this period, the cross-slope flow at the shelf break is characterized by along-slope correlation scales of O(10) km and temporal correlation scales of a few days. The relative dispersion of parcels across isobaths is found to increase with time as tb, where 1 < b < 2. This mixed diffusive–ballistic regime appears to reflect the combined effects of (i) the short length scales of velocity correlation at the shelf break and (ii) the seaward excursion of monopolar and dipolar vortices. Cross-slope dispersion is greater offshore of the front than inshore of the front, as offshore parcels are both subducted onshore below density surfaces and translated offshore with eddies. Nonetheless, the exchange of parcels across the jet remains very limited on the monthly time scale. Particles originating from the bottom experience upward displacements of a few tens of meters and seaward displacements of O(100) km, suggesting that the eddy activity engendered by an unstable along-slope jet provides another mechanism for bottom boundary layer detachment near the shelf edge.
Description
Author Posting. © American Meteorological Society, 2019. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography, 49 (2), (2019): 607-630, doi:10.1175/JPO-D-18-0166.1.
Collections
Suggested Citation
Marchal, Olivier (2019). On material transport by shelfbreak eddies. Journal of Physical Oceanography, 49 (2), 607-630Related items
Showing items related by title, author, creator and subject.
-
A novel lipid binding protein is a factor required for MgATP stimulation of the squid nerve Na+/Ca2+ exchanger
Berberian, Graciela; Bollo, Mariana; Montich, Guillermo; Roberts, Gretel; DeGiorgis, Joseph A.; DiPolo, Reinaldo; Beauge, Luis (2008-11-14)Here we identify a cytosolic factor essential for MgATP up-regulation of the squid nerve Na+/Ca2+ exchanger. Mass spectroscopy and Western blot analysis established that this factor is a member of the lipocalin super ... -
Report on Sediment Transport Events on Shelf and Slope (STRESS) field season 1 : Winter 1988-1989 Benthic Acoustic Stress Sensor (BASS)
Montgomery, Ellyn T.; Dunn, Christopher V. R.; Williams, Albert J. (Woods Hole Oceanographic Institution, 1989-12)Data on the effects of winter conditions on the transport of sediment on the continental shelf off Northern California were collected during the flrst year of the Sediment TRansport Events on Shelf and Slope (STRESS) ... -
Near-surface transport pathways in the north Atlantic Ocean : looking for throughput from the subtropical to the subpolar gyre
Rypina, Irina I.; Pratt, Lawrence J.; Lozier, M. Susan (American Meteorological Society, 2011-05)Motivated by discrepancies between Eulerian transport estimates and the behavior of Lagrangian surface drifters, near-surface transport pathways and processes in the North Atlantic are studied using a combination of data, ...