nerc.ac.uk

Along-shelf evolution and sea levels across the continental slope

Huthnance, J.M.. 1987 Along-shelf evolution and sea levels across the continental slope. Continental Shelf Research, 7 (8). 957-974. 10.1016/0278-4343(87)90008-2

Full text not available from this repository.

Abstract/Summary

f wind-stress or a horizontal oceanic density gradient acts over an ocean basin with an adjacent continental shelf and slope, sea-surface slopes and currents are set up along the shelf and slope with a return flow in the ocean. The currents evolve from zero at blocked ends of the shelf and basin. Such evolution is essentially barotropic (even for baroclinic forcing) and is relevant to all flow adjustments after longshore changes of depth profile or forcing. The distance over which this evolution takes place is investigated analytically for simple geometries, and numerically for a range of shelf, slope and ocean widths, shelf/ocean depth ratios, frictional decay rates and oscillatory frequencies. A close correspondence is found with the decay distance (group velocity x decay time) for a lowest mode continental shelf wave, often exceeding 1000 km. This correspondence is used to interpret some published model calculations of shelf and slope currents or return flows resulting from wind-stress or alongshore pressure gradients. Where a slope current is evolving, coastal sea levels do not follow oceanic levels. Implications for coastal/oceanic level differences are discussed. Oceanic sea-level features of shorter scale than the above 1000 km (say) do not penetrate fully to the coast. However, coastal sea levels averaged around small islands without broad shelves well represent surrounding oceanic levels.

Item Type: Publication - Article
Digital Object Identifier (DOI): 10.1016/0278-4343(87)90008-2
Programmes: POL Programmes
ISSN: 02784343
Date made live: 01 Jul 2013 16:05 +0 (UTC)
URI: http://nora.nerc.ac.uk/id/eprint/502482

Actions (login required)

View Item View Item

Document Downloads

Downloads for past 30 days

Downloads per month over past year

More statistics for this item...