Benthic storms
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A benthic storm (BS), also known as a deep-sea storm, is an episodic period of increased bottom-water turbidity that is capable of sediment resuspension in the deep ocean.[1] They form in response to the instability of surface currents. This leads us o the formation of strong cyclonic and anticyclones currents. They are able to generate deep cyclones, anticyclones, and/or topographic waves. These create currents with sufficient bed-shear stress are able to erode and resuspend sediment from the sea floor causing it to initiate or enhance benthic storms. Particulate matter (PM) eroded from the seafloor from bottom currents also go into forming a nepheloid layer.[2][1][3]
Benthic storms are most frequently occurring beneath Gulf Stream meanders and its associated rings. Other areas where they occur frequently include the New England Seamounts and the North Atlantic Current near the Flemish Cap.[1][3]
Formation
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They occurred in areas with high sea-surface eddy kinetic energy (EKE). It also seems that they require a mixed barotropic–baroclinic instability-driven cyclogenesis to generate. A jet located near the surface developed meanders evolving into alternating and deep reaching cyclones and anticyclones. Simultaneously, the kinetic energy of high surface eddies increases near the bottom due to the convergence of vertical eddy pressure fluxes. They can then form bottom mixed layers that can have thicknesses of 100 meters, mainly from enhanced velocity shears and near-bottom turbulence production. Fluid particles are transported both laterally and vertically from the near bottom through the mixed bottom layer from deep cyclonic eddies. Varying intensities of deep current with distance from the bottom creates turbulence which leads to well-mixed layers. Deep varying transport particles from the near-bottom upward through the entire mixed layers.[2]
Benthic storms seem to show a high range of variability in velocity, intensity, etc.[4][5]