nerc.ac.uk

Storm-driven continental shelf waves over the Scottish continental shelf

Gordon, R. Lee; Huthnance, John M.. 1987 Storm-driven continental shelf waves over the Scottish continental shelf. Continental Shelf Research, 7 (9). 1015-1048. 10.1016/0278-4343(87)90097-5

Full text not available from this repository.

Abstract/Summary

Currents and winds were observed over a 3-year period at two stations on the Scottish continental shelf, near the shelf break east and west of the Shetland Islands. Two types of responses to severe winter storms were observed. The first type was an “oscillatory response” where the currents rotated almost uniformly in the same sense as an inertial motion but with a frequency of about0.6 f (f is the inertial frequency), or a period of about 23 h. The second type of response, a “quasi-steady response”, was an along-isobath current that flowed as long as the wind blew and stopped when the wind stopped. Both responses were barotropic. Typical peak wind stress was 1 Pa or more, and response amplitudes were 0.2–0.4 m s−1. The oscillatory responses were forced by relatively short-duration winds (typically a half day) while the quasi-steady responses were forced by longer-period winds. Both responses appeared to be lowest-mode continental shelf waves (CSW's) but from different places on the dispersion curve. The oscillatory response appears to be a zero-group-velocity CSW which is predicted to “resonate” near the observed frequency. The quasi-steady response is a low-frequency, low-wavenumber CSW in the non-dispersive regime where velocities are constant. We present a model for CSW generation at all frequencies, with particular emphasis on results for the “resonant” regime. This model predicts the dominant characteristics of both the oscillatory and quasi-steady responses and makes reasonable the fact that these dominant characteristics are so well-defined in our data. Baroclinic responses were not observed in severe storms because the storms occurred in the months from December to April when the nearby continental shelf waters are well-mixed, surface to bottom.

Item Type: Publication - Article
Digital Object Identifier (DOI): 10.1016/0278-4343(87)90097-5
Programmes: POL Programmes
ISSN: 02784343
Date made live: 01 Jul 2013 16:02 +0 (UTC)
URI: http://nora.nerc.ac.uk/id/eprint/502481

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...