An analysis of the optical features of the near-bottom and bottom nepheloid layers in the area of the Scotian Rise

• Main Authors: Spinrad, Richard W., Zaneveld, J. Ronald
• Format: Article in Journal/Newspaper
• Language: English; unknown
• Published: American Geophysical Union
• Subjects: North Atlantic
• Online Access: https://ir.library.oregonstate.edu/concern/articles/nv935440c

Profiles of light transmission versus depth have been studied in the region of the Scotian Rise of the North Atlantic at bottom depths between 4900 and 5000 m. A component model has been developed and consists of three components of transmission which can be combined to duplicate accurately any given transmission profile. Two of the components are shown to be representative of several basic phenomena: the particle concentration within a uniform flow and the separation of a benthic nepheloid layer. In the case of a uniform flow it is the relative magnitudes of settling and eddy diffusion which determine the shape of the transmission profile. Separation of the benthic nepheloid layer was inferred to be caused by an occasional cross-slope velocity component. The physical interpretation of the third component was ambiguous. Eulerian and Lagrangian transformations of the data show that benthic 'storms' that were detected at one location and time appeared nearly identical at a later time downstream and that benthic 'storms' can be detected over a large distance. Distance and time scales obtained from these transformations show the area of the Scotian Rise to be one characterized by bottom 'storms' which keep their general form over periods of at least 2 weeks and for distances traveled of at least 400 km.