dc.contributor.author | Stiansen, Jan Erik | |
dc.contributor.author | Sundby, Svein | |
dc.contributor.author | Jenkins, Alastair D. | |
dc.contributor.author | Nilsen, Jan Even Øie | |
dc.date.accessioned | 2007-07-10T12:38:34Z | |
dc.date.issued | 2005 | |
dc.identifier.uri | http://hdl.handle.net/11250/100649 | |
dc.description.abstract | Two field investigations in an exposed shallow area outside Lofoten, western Norway, were
conducted in 1995 and 1996. Direct measurements of turbulence were conducted from an
underwater tower with acoustic current meters 6 m above the bottom. The tidal energy in this
area is low and the wind conditions during the experiment were mostly weak. Nevertheless,
the turbulent kinetic energy dissipation rate at 20-25 m depth was in the range 10-7-10-5 W/kg.
The only other possible energy source was long swell of wavelength 100-200 m that rolled in
from the open sea. Analysis shows that the wave related water motion intermittently becomes
unstable, inducing strong turbulent patches in parts of the wave orbit. The mechanism behind
this process is not clear, but possible explanations may be local energy concentration or
interaction of waves with different frequency. In many areas and situations this energy source is equal in force to tidal and wind generated turbulence. Simultaneous measurement of vertical profiles of zooplankton and fish larvae from a nearby location enables us to discuss swell-induced turbulence in an ecological context. | en |
dc.format.extent | 374017 bytes | |
dc.format.mimetype | application/pdf | |
dc.language.iso | eng | en |
dc.publisher | ICES | en |
dc.relation.ispartofseries | ICES CM documents | en |
dc.relation.ispartofseries | 2005/O:26 | en |
dc.subject | fish larvae | en |
dc.subject | zooplankton | en |
dc.subject | hydrography | en |
dc.subject | fiskelarver | |
dc.subject | dyreplankton | |
dc.subject | hydrografi | |
dc.title | Swell as a turbulence source in shallow water | en |
dc.type | Working paper | en |
dc.subject.nsi | VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 | |
dc.subject.nsi | VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: | |
dc.subject.nsi | VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 | |
dc.source.pagenumber | 10 s. | en |