The thermohaline circulation and the exchanges between the Nordic Seas and the North Atlantic

  • Participating scientists
  • Bert Rudels (project leader)
  • Marika Marnela
  • Aleksi Nummelin

Project goals

The project studies the water mass formation processes in the Arctic Mediterranean Sea and aims to determine the water masses contributing to the Denmark Strait overflow. The dynamics and mixing of the overflow plume with ambient water masses and the contribution of entrainment to the Atlantic Meridional Overturning Circulation are also examined.

The studies involve fieldwork and data collection, the study of entrainment through dedicated turbulence experiments in the field, as well as analysis of historical data and the formulation of an adequate description of the entrainment process bringing ambient water into the overflow plume.

The project is a cooperation with FMI and has received funding and developed from the EU project VEINS (Variability of Exchanges In the Northern Seas) (1997-2000), ASOF-W (Arctic-Subarctic Ocean Fluxes) (2003-2005) and is now a part of the EU THOR project (ThermoHaline Overturning – at Risk?) (2008-2012).

Over the years a close cooperation has developed with the Department of Oceanography at the University of Hamburg. Within THOR the turbulence studies will be done in cooperation with Shirshov Institute of Oceanology in Kaliningrad and Moscow.

Relevant publications:

  • Rudels, B., Eriksson, P., Grönvall, H., Hietala, R. & Launiainen, J. 1999. Hydrographic Observations in Denmark Strait in fall 1997, and their Implications for the Entrainment into the Overflow Plume. Gephys. Res. Letters, 26, 1325-1328.
  • Rudels, B., Friedrich, H.J. & Quadfasel, D. 1999: The Arctic Circumpolar Boundary Current. Deep-Sea Research Part II, 46, 1023-1062.
  • Rudels, B., Fahrbach, E., Meincke, J., Budéus, G. and Eriksson, P. 2002: The East Greenland Current and its contribution to the Denmark Strait overflow. ICES Journal of Marine Sciences, 59, 1133-1154.
  • Rudels, B., Eriksson, P., Buch, E., Budéus, G., Fahrbach, E., Malmberg, S.-A., Meincke, J. and Mälkki, P. 2003: Temporal switching between sources of the Denmark Strait overflow water. ICES Marine Science Symposia: Hydrobiological variability in the ICES area, 1990-1999, Edinburgh, Scotland, 8-10 August 2001: Actes du Symposium: Poster presented at the Symposium 219, 319-325.
  • Rudels, B., Björk, G., Nilsson, J., Winsor, P., Lake, I. and Nohr, C. 2005: The interaction between waters from the Arctic Ocean and the Nordic Seas north of Fram Strait and along the East Greenland Current: results from the Arctic Ocean-02 Oden expedition. Journal of Marine Systems 55, 1-30.
  • Dickson, R.R. Dye, S., Jonsson, S., Köhl, A., Macrander, A., Marnela, A., Meincke, J., Olsen, S., Rudels, B., Valdimarsson, H. and Voet, G. (2008) The overflow flux west of Iceland: variability, origins and forcing. In R.R Dickson, J. Meincke & P. Rhines: Arctic – Subarctic Ocean Fluxes, Springer, Dordrecht, 443-474.
  • Jeansson, E., Jutterström, S., Rudels, B., Anderson, L.G., Olsson, K.A., Jones, E.P., Smethie Jr., W.H. and Swift, J.H. (2008) Sources to the East Greenland Current and its contribution to the Denmark Strait overflow. Progress in Oceanography 78, 12-28 doi:10.1016/j.pocean.2007.06.00x.