• Baines, P. G., 1982: On internal tide generation models. Deep-Sea Res.,29, 307–338.

  • de Young, B., and S. Pond, 1989: Partition of energy loss from the barotropic tide in fjords. J. Phys. Oceanogr.,19, 246–252.

  • Djurfeldt, L., 1987: On the response of the fjord Gullmaren under ice cover. J. Geophys. Res.,92, 5157–5167.

  • Garrett, C., and W. H. Munk, 1972: Space-time scales of internal waves. Geophys. Fluid Dyn.,2, 225–264.

  • ——, and ——, 1975: Space-time scales of internal waves. A progress report. J. Geophys. Res.,80, 291–297.

  • Gill, A. E., 1982: Atmosphere Ocean Dynamics. Academic Press, 662 pp.

  • Gustafsson, B., and A. Stigebrandt, 1996: Dynamics of the freshwater-influenced surface layers in the Skagerrak. Neth. J. Sea Res.,35, 39–53.

  • Kullenberg, B., 1932: A recording boundary gauge for the open sea. Göteborgs Vetensk-Vitterhets-Samh. Handl,Ser. B,9, 1–9.

  • Pettersson, H., 1917: Stående vågor i havet. Medd. Geogr. Föreningen i Göteborg 1917,2, 29–44.

  • ——, 1921: Meteorological influences on the level of the sea-surface. Geogr. Annaler 1921,H. 1–2, 165–182.

  • Proudman, J., 1953: Dynamical Oceanography. Methuen, 409 pp.

  • Rattray, M., 1960: On the coastal generation of internal tides. Tellus,12, 54–62.

  • Shaffer, G., and L. Djurfeldt, 1983: On the low frequency fluctuations in Skagerrak and Gullmaren. J. Phys. Oceanogr.,13, 1321–1340.

  • Sjöberg, B., and A. Stigebrandt, 1992: Computations of the geographical distribution of the energy flux to mixing processes via internal tides and the associated vertical circulation in the ocean. Deep-Sea Res.,39, 269–291.

  • Stigebrandt, A., 1976: Vertical diffusion driven by internal waves in a sill fjord. J. Phys. Oceanogr.,6, 486–495.

  • ——, 1980: Some aspects of tidal interaction with fjord constrictions. Estuar. Coastal Mar. Sci.,11, 151–166.

  • ——, and J. Aure, 1989: On vertical mixing in basin waters of fjords. J. Phys. Oceanogr.,19, 917–926.

  • Svansson, A., 1984: Hydrography of the Gullmar Fjord. Medd. Havsfiskelaboratoriet, Lysekil.,297, 1–21.

  • Thompson, R. O. R. Y., 1979: Coherence significance levels. J. Atmos. Sci.,36, 2020–2021.

  • Zeilon, N., 1912: On the tidal boundary waves and related hydrodynamical problems. Kungl. Svenska Vetenskapsakademiens Handlingar, Vol. 47 (4), 46 pp.

  • ——, 1913: On the seiches of the Gullmar Fjord. Sven. Hydrogr. Biol. Komm. Skr.,V, 1–17.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 5 5 5
PDF Downloads 8 8 8

Observed Damping of Barotropic Seiches through Baroclinic Wave Drag in the Gullmar Fjord

View More View Less
  • 1 Department of Oceanography, University of Göteborg, Göteborg, Sweden
Restricted access

Abstract

Baroclinic wave drag, due to internal wave generation at steep topography, is shown to be a mechanism that effectively subdues barotropic seiches in fjords. A two-layer model for a fjord with a sill at the mouth is applied to the Gullmar Fjord, Sweden. The damping of the fundamental seiche mode observed from sea level records is well predicted by the model. This includes the observed seasonal variation in damping due to the corresponding variation in vertical stratification. It is shown that ordinary bottom friction should contribute less than 1% to the damping in this fjord.

Simultaneous current records from different depths, obtained on the slope of the sill in the fjord, are analyzed. Spectra of all records show a significant energy peak at the seiche frequency. The vertical variation of the phase of the current at this frequency shows that the motion is essentially baroclinic.

Corresponding author address: Dr. Richard Parsmar, Department of Oceanography, Earth Science Center, University of Göteborg, S-413 81 Göteborg, Sweden.

Email: ripa@.oce.gu.se

Abstract

Baroclinic wave drag, due to internal wave generation at steep topography, is shown to be a mechanism that effectively subdues barotropic seiches in fjords. A two-layer model for a fjord with a sill at the mouth is applied to the Gullmar Fjord, Sweden. The damping of the fundamental seiche mode observed from sea level records is well predicted by the model. This includes the observed seasonal variation in damping due to the corresponding variation in vertical stratification. It is shown that ordinary bottom friction should contribute less than 1% to the damping in this fjord.

Simultaneous current records from different depths, obtained on the slope of the sill in the fjord, are analyzed. Spectra of all records show a significant energy peak at the seiche frequency. The vertical variation of the phase of the current at this frequency shows that the motion is essentially baroclinic.

Corresponding author address: Dr. Richard Parsmar, Department of Oceanography, Earth Science Center, University of Göteborg, S-413 81 Göteborg, Sweden.

Email: ripa@.oce.gu.se

Save