On the North Atlantic Circulation

Reviews of Geophysics - Tập 31 Số 1 - Trang 29-49 - 1993
William J. Schmitz, Michael S. McCartney

Tóm tắt

A new, speculative, and, we hope, provocative summary of the North Atlantic circulation is described, including both horizontal currents (wind‐driven) and the primarily (thermohaline) meridional flows that involve the transformation of warm to cold water at high latitudes. Our picture is based on a synthesis of a variety of independent investigations that are contained in the literature as opposed to a presentation of the results of one technique or the point of view of one author. We describe a thermohaline cell (the so‐called thermohaline conveyor belt) that is concentrated within the Atlantic and Southern oceans (rather than essentially global), with the most important upwelling sites being in the circumpolar and the equatorial current regimes. We concentrate on deep water formation and its replacement relative to intermediate‐water formation. It has been pointed out recently that the formation of 13 Sv (1 Sv = 106m³ s−1) of southward flowing North Atlantic Deep Water is compensated for in the upper ocean by northward cross‐equatorial transport. We suggest that this thermocline layer flow passes through the Straits of Florida, transits the Gulf Stream system on its inshore side, and exits through the North Atlantic Current system after recirculation and modification. There is now a clear observational basis for the structure of recirculating gyres on the southern and northern sides of the Gulf Stream. We suggest a recirculation for the North Atlantic Current as well. We also describe a C‐shaped component to the southern Gulf Stream recirculation and identify a roughly 10‐Sv circulation in the eastern North Atlantic associated with the Azores Current. Recirculations play an important role in deep boundary current regimes and in water mass formation and modification. The transport of the deep western and northern boundary currents in the North Atlantic Ocean may be boosted (roughly doubled or tripled) by counterclockwise recirculating gyres and by additions of modified bottom or intermediate water. While the North Atlantic is the most completely observed ocean, there are still significant gaps in our knowledge of its circulation.

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Tài liệu tham khảo

10.1029/JC088iC08p04699

10.1175/1520-0485(1991)021<0221:MMWSAS>2.0.CO;2

10.5670/oceanog.1991.07

10.1029/JC083iC12p06179

10.1016/S0198-0149(12)80020-3

Bubnov V. A., 1979, Study of water circulation in the tropical Atlantic, Deep Sea Res., 26, 125

10.1029/91JC02569

Clarke R. A., 1984, Transport through the Cape Farewell‐Flemish Cap section, Rapp. P. V. Reun. Cons. Int. Explor. Mer., 185, 120

10.1175/1520-0485(1980)010<0025:CSSAEO>2.0.CO;2

10.1175/1520-0485(1979)009<0724:SCITWE>2.0.CO;2

10.1175/1520-0485(1986)016<1703:CGT>2.0.CO;2

10.1175/1520-0485(1992)022<0918:OTFOAI>2.0.CO;2

10.1175/1520-0485(1993)023<1553:TMFAIW>2.0.CO;2

10.1016/0198-0149(88)90096-9

Finlen J. R. Transport investigations in the Northwest Providence Channel Master of Science thesis 110 pp. Univ. of Miami Coral Gables Fl. 1966.

10.1029/JC091iC04p05037

10.1029/92JC00485

10.1175/1520-0485(1985)015<1439:TSATOT>2.0.CO;2

10.1016/0198-0149(82)90099-1

10.1175/1520-0485(1993)023<0225:DDOTGS>2.0.CO;2

10.1016/0198-0149(92)90066-3

Hogg N., 1982, On the transport and modification of Antarctic Bottom Water in the Vema Channel, J. Mar. Res., 40, 231

Ivers W. D. The deep circulation in the northern North Atlantic with especial reference to the Labrador Sea Ph.D. thesis 179 pp. Univ. of Calif. at San Diego 1975.

Johns W. E., 1993, Deep western boundary current variability off northeastern Brazil, J. Phys. Oceanogr.

Kirwan A. D. Circulation of Antarctic Intermediate Water deduced through isentropic analysisRef. 63‐34F 34Texas A & M Univ. College Station 1963.

Lazier J. R. N., 1993, Renewal of subpolar water in the North Atlantic Ocean, J. Phys. Oceanogr.

10.1175/1520-0485(1990)020<0467:OTAATO>2.0.CO;2

10.1175/1520-0485(1990)020<0446:WBCSAV>2.0.CO;2

Leetmaa A., 1978, Updated charts of the mean annual wind stress, convergences in the Ekman layers, and Sverdrup transports in the North Atlantic, J. Mar. Res., 36, 311

Leetmaa A., 1977, Does the Sverdrup relation account for the mid‐Atlantic circulation?, J. Mar. Res., 35, 1

10.1016/0011-7471(67)90077-0

McCartney M. S., 1977, A Voyage of Discovery, George Deacon 70th Anniv. Vol, 103

McCartney M. S., 1982, The subtropical recirculation of Mode Waters, J. Mar. Res., 40, 427

10.1016/0079-6611(92)90006-L

10.1175/1520-0485(1993)023<1953:COTEBT>2.0.CO;2

10.1175/1520-0485(1993)023<1264:TFOABW>2.0.CO;2

10.1175/1520-0485(1982)012<1169:TSMWOT>2.0.CO;2

10.1175/1520-0485(1984)014<0922:WTCWCI>2.0.CO;2

10.1175/1520-0485(1991)021<1089:EFTTMA>2.0.CO;2

10.1029/JZ072i020p04959

10.1016/0198-0149(92)90008-H

Montgomery R. B., 1942, Sigma‐t surfaces in the Atlantic Ocean, J. Mar. Res., 5, 20

10.1175/1520-0485(1993)023<2602:HDTDWB>2.0.CO;2

10.1029/JC083iC10p05063

10.1016/0198-0149(79)90064-5

10.1175/1520-0477-65.11.1219

10.1016/0011-7471(71)90094-5

10.1016/0146-6291(77)90549-5

10.1357/002224085788437343

10.1016/0011-7471(71)90095-7

10.1029/93JC00051

Richardson W. S., 1969, The velocity structure of the Florida Current from the Straits of Florida to Cape Fear, Deep Sea Res., 16, 225

10.1029/90JC02422

10.1175/1520-0485(1980)010<1972:EOMHFI>2.0.CO;2

10.1029/JC086iC09p07993

10.1175/1520-0485(1983)013<1534:TBOGAE>2.0.CO;2

10.1016/0198-0149(85)90070-6

Saunders P. M., 1982, Circulation in the eastern North Atlantic, J. Mar. Res., 40, 641

10.1016/0011-7471(68)90081-8

Schmitz W. J., 1991, On the sources of the Florida Current, Deep Sea Res., 38, S389

10.1029/92JC00417

Schmitz W. J., 1993, On the Florida Current T/S envelope, Bull. Mar. Sci.

10.1029/91JC02501

10.1016/0146-6313(56)90048-X

Stommel H., 1965, The Gulf Stream, A Physical and Dynamical Description, 10.1525/9780520318564

Stommel H., 1978, Dynamic topography and recirculation of the North Atlantic, J. Mar. Res., 36, 449

10.1357/002224084788506022

10.1016/0198-0149(88)90017-9

10.1175/1520-0485(1982)012<1189:DACOLS>2.0.CO;2

10.1357/002224089785076136

10.1016/0198-0149(92)90004-D

Wennekens M. P., 1959, Water mass properties of the Straits of Florida and related waters, Bull. Mar. Sci. Gulf Caribb., 9, 1

Worthington L. V., 1962, Evidence for a two‐gyre circulation system in the North Atlantic, Deep Sea Res., 9, 51

Worthington L. V. On the North Atlantic circulation The Johns Hopkins Oceanogr. Stud. 6 110 1976.

10.1175/1520-0485(1984)014<1712:AEAOCM>2.0.CO;2

10.1175/1520-0485(1985)015<1876:ITNAIS>2.0.CO;2

Wüst G. Schichtung und Zirkulation des Atlantischen Ozeans Die Stratosphäre in: Wiss. Ergebn. Dtsch. Atl. Exped. 6 Part 1 2 180 pp. 1935. (in English translation:The Stratosphere of the Atlantic Ocean edited byW. J.Emery 112 pp. Amerind New Delhi India 1978.).

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Reviews of Geophysics

Tập 31 Số 1

29-49

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