Benthic storms, nepheloid layers, and linkage with upper ocean dynamics in the western North Atlantic
Figure S4. Video of BOM S time-series photographs of a ~ 61 × 46 cm area of the seafloor taken over the full duration of the deployment. (308.5Mb)
Gardner, Wilford D.
Tucholke, Brian E.
Richardson, Mary Josephine
MetadataShow full item record
KeywordBenthic storms; Benthic nepheloid layer; Abyssal currents; Seafloor erosion; Eddy kinetic energy; Cyclogenesis
Benthic storms are episodic periods of strong abyssal currents and intense, benthic nepheloid (turbid) layer development. In order to interpret the driving forces that create and sustain these storms, we synthesize measurements of deep ocean currents, nephelometer-based particulate matter (PM) concentrations, and seafloor time-series photographs collected during several science programs that spanned two decades in the western North Atlantic. Benthic storms occurred in areas with high sea-surface eddy kinetic energy, and they most frequently occurred beneath the meandering Gulf Stream or its associated rings, which generate deep cyclones, anticyclones, and/or topographic waves; these create currents with sufficient bed-shear stress to erode and resuspend sediment, thus initiating or enhancing benthic storms. Occasionally, strong currents do not correspond with large increases in PM concentrations, suggesting that easily erodible sediment was previously swept away. Periods of moderate to low currents associated with high PM concentrations are also observed; these are interpreted as advection of PM delivered as storm tails from distal storm events. Outside of areas with high surface and deep eddy kinetic energy, benthic nepheloid layers are weak to non-existent, indicating that benthic storms are necessary to create and maintain strong nepheloid layers. Origins and intensities of benthic storms are best identified using a combination of time-series measurements of bottom currents, PM concentration, and bottom photographs, and these should be coupled with water-column and surface-circulation data to better interpret the specific relations between shallow and deep circulation patterns. Understanding the generation of benthic nepheloid layers is necessary in order to properly interpret PM distribution and its influence on global biogeochemistry.
© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marine Geology 385 (2017): 304–327, doi:10.1016/j.margeo.2016.12.012.
Suggested CitationArticle: Gardner, Wilford D., Tucholke, Brian E., Richardson, Mary Josephine, Biscaye, Pierre, "Benthic storms, nepheloid layers, and linkage with upper ocean dynamics in the western North Atlantic", Marine Geology 385 (2017): 304–327, DOI:10.1016/j.margeo.2016.12.012, https://hdl.handle.net/1912/8971
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivatives 4.0 International
Showing items related by title, author, creator and subject.
Significance of cyclonic SubTropical Oceanic Rings of Magnitude (STORM) eddies for the carbon budget of the euphotic layer in the subtropical northeast Atlantic Mourino, Beatriz; Fernandez, Emilio; Etienne, Helene; Hernandez, Fabrice; Giraud, Sylvie (American Geophysical Union, 2003-12-20)The interannual and seasonal variability of cyclonic eddies budded from the Azores Current during the period 1993–1999 in the northeast subtropical Atlantic region (20°N–34°N; 19°W–35°W) was studied by using TOPEX/Poseidon ...
The HEBBLE II report : proceedings of the second annual workshop on the High Energy Benthic Boundary Layer Experiment held at the Keystone Center for Continuing Education, March 19-24, 1979 Williams, Albert J.; Hollister, Charles D.; Chandler, Richard S. (Woods Hole Oceanographic Institution, 1979-08)In 1978, the first Keystone Conference addressed the scientific problems of sediment transport in a high energy flow such as the Western Boundary Undercurrent. Sedimentologists, physical oceanographers, geologists, optical ...
The third annual report of the High Energy Benthic Boundary Layer Experiment : proceedings of the Keystone III Conference held at the Keystone Center for Continuous Education, March 11-15, 1980 Hollister, Charles D.; Nowell, Arthur R. M.; Smith, J. Dungan (Woods Hole Oceanographic Institution, 1980-07)A meeting was held March 11-15, 1980 to develop and refine the hierarchy of problems to be addressed by the high energy benthic boundary layer experiment. This document outlines revised program goals and the critical ...