An overview of the teta - S correlations in Fram Strait based on the MIZEX 84 data

• Autorzy: Schlichtholz P. , Houssais M.N.
• Języki publikacji: EN

Abstrakty

EN

The water masses in Fram Strait have been analyzed on the basis of hydrographic casts taken in summer 1984 during the MIZEX 84 experiment. In particular, θ − S diagrams for 16 areas, each 5◦ in longitude and 1◦ in latitude, covering the strait from 77◦N to 81◦ N are used to characterize the water masses and discuss their possible origin. Near the surface, the East Greenland Polar Front clearly separates the lighter, cold and fresh Polar Water (PW) from the heavier, warm and saline Atlantic Water (AW). In the upper ocean, the data show a large spreading of the temperature maximum in the θ − S space associated with different modes of the AW recirculating southward below the PW. Two geographically distinct salinity minima are found in the intermediate layer below the AW. The denser one, in the Boreas Basin, is a feature typical of the Arctic Intermediate Water (AIW) formed by winter convection to the south of the strait, while the lighter one is sandwiched in the Arctic Ocean outflow between the AW layer and the Upper Polar Deep Water (UPDW) characterized by a downward salinity increase. In the deep layer, two salinity maxima are present. The shallower (and warmer) one, associated with the Canadian Basin Deep Water (CBDW), appears all along the East Greenland Slope. A similar but weaker maximum is also found in the southeastern part of the strait. This maximum is perhaps a remnant of the maximum in the East Greenland Current after it has been recirculated back to the strait around the cyclonic gyres of the Nordic Seas. The deeper one appears typically as a near-bottom salinity jump characteristic of the Eurasian Basin Deep Water (EBDW). The jump is found in two distinct areas of the strait, to the north-west in the Lena Trough and to the south-east in the rift valley of the Knipovich Ridge. The maximum in the former area should have been advected from the Arctic Ocean below the CBDW, while the maximum in the latter area might have originated from haline convection on the adjacent shelves. Some EBDW is trapped in the Molloy Deep over a denser water with salinity decreasing down to the bottom and temperature in the range of the Greenland Sea Deep Water (GSDW).

Słowa kluczowe

EN

temperature; Fram Strait; Atlantic water; hydrographic cast; MIZEX 84 experiment; teta-S diagram; water mass; salinity; Arctic Ocean

• Wydawca: -
• Czasopismo: Oceanologia
• Rocznik: 2002
• Tom: 44
• Numer: 2
• Opis fizyczny: p.243-272,fig.,ref.

Twórcy

autor

Schlichtholz P.

• Polish Academy of Sciences, Powstancow Warszawy 55, 81-712 Sopot, Poland

autor

Houssais M.N.

Bibliografia

• Aagaard K., Carmack E.C., 1989, The role of sea ice and other fresh water in the Arctic circulation, J. Geophys. Res., 94, 14,485–14,498.
• Aagaard K., Fahrbach E., Meincke J., Swift J.H., 1991, Saline outflow from the Arctic Ocean: Its contribution to the deep waters of the Greenland, Norwegian, and Iceland Seas, J. Geophys. Res., 96, 4833–4846.
• Aagaard K., Greisman L.K., 1975, Toward new mass and heat budgets for the Arctic, J. Geophys. Res., 80, 3821–3827.
• Aagaard K., Swift J.H., Carmack E.C., 1985, Thermohaline circulation in the Arctic Mediterranean Seas, J. Geophys. Res., 90, 4833–4846.
• Anderson L.G., Bj¨ork G., Holby O., Jones E., Kattner P. K., Lilieblad B., Rudels B., Swift J.H., 1994, Water masses and circulation in the Eurasian Basin: Results from the Oden 91 expedition, J. Geophys. Res., 99, 3273–3283.
• Anderson L.G., Jones E.P., Koltermann K.P., Schlosser P., Swift J.H., Wllace D.W.R., 1989, The first oceanographic section across the Nansen Basin in the Arctic Ocean, Deep-Sea Res., 36, 475–482.
• Bourke R.H., Newton J. L., Paquette R. G., TunnicliffeM.D., 1987, Circulation and water masses of the East Greenland Shelf, J. Geophys. Res., 92, 6729–640.
• Boyd T. J., D’Asaro E.A., 1994, Cooling of the West Spitsbergen Current, J. Geophys. Res., 99, 22,597–22,618.
• Buch E., Malmberg S.-A., Kristmannsson S. S., 1996, Arctic Ocean deep water masses in the western Iceland Sea, J. Geophys. Res., 101, 11965–11973.
• Budéus G., Schneider W., Krause G., 1998, Winter convective events and bottom water warming in the Greenland Sea, J. Geophys. Res., 103, 18,513–18,528.
• Carmack E.C., Macdonald R.W., Perkin R.G., McLaughlin A., 1995, Evidence for warming of Atlantic water in the southern Canadian Basin of the Arctic Ocean: Results from the Larsen-93 expedition, Geophys. Res. Lett., 22, 1061–1064.
• Clarke R.A., Swift J.H., Reid J. L., Koltermann K.P., 1990, The formation of Greenland Sea Deep Water: Double diffusion or deep convection?, Deep-Sea Res., 37, 1385–1424.
• Dickson R., Lazier J., Meincke J., Rhines P., Swift J.H., 1996, Long-term coordinated changes in the convective activity of the North Atlantic, Prog. Oceanogr., 38, 241–295.
• Dickson R.R., Meincke J., Malmberg S.A., Lee A. J., 1988, The ‘Great Salinity Anomaly’ in the northern North Atlantic, Prog. Oceanogr., 20, 103–151.
• Dickson R.R., Osborn T. J., Hurrell J. W., Meincke J., Blindheim J., Adlandsvik B., Vinje T., Alekseev G., Maslowski W., 2000, The Arctic Ocean response to the North Atlantic Oscillation, J. Climate, 13, 2671–2696.
• Fahrbach E., Meincke J., Østerhus S., Rohardt G., Schauer U., Tverberg V., Verduin J., 2000, Direct measurements of volume transports through Fram Strait, Polar Res., 20, 217–224.
• Friedrich H., Houssais M.-N., Quadfasel D., Rudels B., 1995, On Fram Strait water masses, Nordic Seas Symp., Extended abstract, Hamburg 7 March–9 March, 69–72.
• Gascard J.-C., Kergomard C., Jeannin P.-F., Fily M., 1988, Diagnostic study of the Fram Strait marginal ice zone during summer from 1983 and 1984 Marginal Ice Zone Experiment lagrangian observations, J. Geophys. Res., 93, 3613–3641.
• Grotefendt K., Logemann K., Quadfasel D., Ronski D., 1998, Is the Arctic Ocean warming?, J. Geophys. Res., 103, 27,679–27,687.
• Hunkins K., 1990, A review of the physical oceanography of Fram Strait, [in:] The physical oceanography of Sea Straits, I. Pratt (ed.), Kluwer Acad. Publ., Netherlands, 61–93.
• Johannessen J.A., Johannessen O.M., Svendsen E., Shuchman R., Manley T., Campbell W. J., Josberger E.G., Sandven S., Gascard J.-C., Olaussen T., Davidson K., Van Leer J., 1987, Mesoscale eddies in Fram Strait mariginal ice zone during the 1983 and 1984 Mariginal Ice Zone Experiments, J. Geophys .Res., 92, 6754–6772.
• Jones E.P., Rudels B., Anderson L.G., 1995, Deep waters of the Arctic Ocean: origins and circulation, Deep-Sea Res., 42, 737–760.
• Josberger E.G., 1987, Bottom ablation and heat transfer coefficients from the 1983 Marginal Ice Zone experiments, J. Geophys. Res., 92, 7012–7016.
• Morison J.H., McPhee M.G., Maykut G.A., 1987, Boundary layer, upper ocean, and ice observations in the Greenland Sea mariginal ice zone, J. Geophys. Res., 92, 6987–7011.
• Muench R.D., McPhee M.G., Paulson C.A., Morison J., 1992, Winter oceanographic conditions in the Fram Strait-Yermak Plateau region, J. Geophys. Res., 97, 3469–3484.
• Quadfasel D., Rudels B., Kurtz K., 1988, Outflow of dense water from a Svalbard fjord into the Fram Strait, Deep-Sea Res., 35, 1143–1150.
• Rudels B., 1987, On the mass balance of the Polar Ocean with special emphasis on the Fram Strait, Norsk Polarinst. Skr., 188, 1–53.
• Rudels B., 1989, The formation of polar surface water, the ice export and the exchanges through the Fram Strait, Prog. Oceanogr., 22, 205–248.
• Rudels B., Friedrich H. J., Quadfasel D., 1999, The Arctic Circumpolar Boundary Current, Deep-Sea Res., Part II, 46, 1023–1062.
• Rudels B., Jones E.P., Anderson L.G., Kattner G., 1994, On the intermediate depth waters of the Arctic Ocean, [in:] The role of the Polar Oceans in shaping the global climate, R. Muench, O. Johannessen (eds.), Amer. Geophys. Union, New York, 33–46.
• Rudels B., Meyer R., Fahrbah E., Ivanov V.V., Østerhus S., Quadfasel D., 2000, Water mass distribution in Fram Strait and over the Yermak Plateau, Ann. Geophys., 18, 687–705.
• Rudels B., Quadfasel D., 1991, Convection and deep water formation in the Arctic Ocean – Greenland Sea System, J. Mar. Sys., 2, 435–450.
• Schauer U., 1995, The release of brine-enriched shelf water from Storfjord into the Norwegian Sea, J. Geophys. Res., 100, 16,015–16,028.
• Schauer U., Muench R.D., Rudels B., Timokhov L., 1997, Impact of eastern Arctic shelf waters on the Nansen Basin intermediate layers, J. Geophys. Res., 102, 3371–3382.
• Schlichtholz P., Houssais M.-N., 1999a, An inverse modeling study in Fram Strait. Part I: Dynamics and circulation, Deep-Sea Res., Part II, 46, 1083–1135.
• Schlichtholz P., Houssais M.-N., 1999b, An inverse modeling study in Fram Strait. Part II: Water mass distribution and transports, Deep-Sea Res., Part II, 46, 1137–1168.
• Schlichtholz P., Houssais M.-N., 1999c, An investigation of the dynamics of the East Greenland Current in Fram Strait based on a simple analytical model, J. Phys. Oceanogr., 29, 2240–2265.
• Smethie W.M., Chipman J.D.W., Swift J.H., Koltermann K.P., 1988, Chlorofluoromethanes in the Arctic Mediterranean seas: evidence for formation of bottom water in the Eurasian Basin and deep water exchange through Fram Strait, Deep-Sea Res., 35, 347–369.
• Strass V., Fahrbach E., Shauer U., Sellmann L., 1993, Formation of Denmark Strait overflow water by mixing in the East Greenland Current, J. Geophys. Res., 98, 6907–6919.
• Swift J.H., 1986, The Arctic Waters, [in:] The Nordic Seas, B.G. Hurdle (ed.), Springer-Verlag, New York–Berlin, 129–153.
• Swift J.H., Aagaard K., 1981, Seasonal transitions and water mass formation in the Iceland and Greenland Seas, Deep-Sea Res., 28A, 1107–1129.
• Swift J.H., Koltermann K.P., 1988, The origin of Norwegian Sea Deep Water, J. Geophys. Res, 93, 3563–3569.
• Zhang J.D., Rothrock D.A., Steele M., 1998, Warming of the Arctic Ocean by a strengthened Atlantic inflow: Model results, Geophys. Res. Lett., 25, 1745–1748.