Changes in the flow of Atlantic water into the Arctic Ocean since the last deglaciation: Evidence from the northern Svalbard continental margin, 80°N

American Geophysical Union (AGU) - Tập 20 Số 4 - 2005
Marta A. Ślubowska1,2, Nalân Koç3, Tine L. Rasmussen1, Dorthe Klitgaard‐Kristensen3
1Department of Geology, University of Tromsø, Tromsø, Norway
2The University Centre in Svalbard, Longyearbyen, Norway
3Norwegian Polar Institute, Polar Environmental Centre, Tromso, Norway

Tóm tắt

The Svalbard archipelago is located in the high Arctic (76°–80°N) within the northernmost reach of the West Spitsbergen Current, which is the continuation of the North Atlantic Current. In this specific setting close to the Polar Front, even small variations in the current system are expected to give large and distinct signals in paleoceanographic parameters. Thus the Svalbard area is ideal for monitoring the past history of the inflow of Atlantic water to the Arctic Ocean. We have studied sediment core NP94‐51 taken outside the mouth of the Hinlopen Strait on the northern Svalbard shelf. The paleoceanographic development of the last deglaciation and the Holocene has been reconstructed using benthic and planktonic foraminifera, oxygen isotopes, and ice‐rafted detritus. The results show that the first strong subsurface inflow of Atlantic water to the Arctic Ocean after the Last Glacial Maximum commenced at 12.6 14C kyr B.P. (circa 15,000 calendar (cal) years B.P.) during the Bølling‐Allerød interstadial. During the Younger Dryas, polar conditions prevailed at the surface with extensive sea ice cover, and the inflow of Atlantic‐derived water was generally diminished. The inflow of more saline, but still cold Atlantic water was relatively strong during the early Holocene and caused intensified seasonal biological productivity. The Atlantic water inflow declined gradually during the mid‐Holocene. Between 4500 and 1100 cal years B.P. the inflow was very weak, and the bottom waters over the northern Svalbard margin were cold and of lower salinity. During the last ∼1000 years, climatic conditions improved such that the subsurface inflow of Atlantic‐derived water increased. However, the surface waters were still cold.

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Tài liệu tham khảo

10.1029/JC094iC10p14485

10.1029/JC080i027p03821

10.1029/JC092iC04p03778

10.1029/2002PA000873

10.1016/S0277-3791(02)00035-5

10.1029/2000GL012556

10.3354/meps303167

10.1016/0033-5894(78)90064-9

10.1111/j.1502-3885.2002.tb01077.x

10.1126/science.274.5290.1155

10.1002/(SICI)1099-1417(199711/12)12:6<455::AID-JQS316>3.0.CO;2-S

10.1016/S0277-3791(03)00002-7

Cadman V.(1996) Glaciomarine sedimentation and environments during the late Weichselian and Holocene in the Bellsund Trough and Van Keulenfjorden Svalbard Ph.D. thesis 250 pp. Univ. of Cambridge U.K.

10.1007/BF02262816

10.1175/1520-0477(1993)074<0033:RVOSIA>2.0.CO;2

10.1029/2002GL015650

10.1175/1520-0442(2003)016<3498:WTITAF>2.0.CO;2

10.1063/1.1801866

10.1016/0016-7037(96)00263-3

10.1016/0377-8398(91)90014-W

10.1175/1520-0442(2000)013<2671:TAORTT>2.0.CO;2

10.3189/S002214300000455X

Duplessy J. C., 1978, Climate Change, 46

10.1038/286479a0

10.1111/j.1502-3885.2001.tb00984.x

10.1130/G20653.1

10.1086/629718

10.1038/342637a0

10.1016/j.quascirev.2003.12.007

10.3354/meps058053

10.1029/98JC02097

10.1111/j.1502-3885.1997.tb00648.x

10.2113/gsjfr.27.2.101

10.2113/gsjfr.22.4.347

Hald M., 1996, Benthic foraminifera and carbonate dissolution in the surface sediments of the Barents and Kara Seas, Ber. Polarforsch., 212, 285

10.1016/0377-8398(87)90018-1

Hald M., 1994, Recent and late Quaternary distribution of Elphidium excavatum f. clavatum in the Arctic seas, Cushman Found. Spec. Publ., 32, 141

Hald M., 1996, Late Quaternary Paleoceanography of the North Atlantic Margins, 275

10.1016/S0031-0182(98)00133-3

10.1111/j.1751-8369.2001.tb00036.x

10.1016/j.quascirev.2004.08.006

V. Hisdal 1998 Nor. Polarinst. Oslo

10.2113/gsjfr.24.2.123

10.2113/34.3.180

10.1126/science.286.5446.1937

10.1111/j.1600-0870.2004.00060.x

10.1029/1999PA000495

10.1016/S0025-3227(99)00106-1

Knudsen K. L., 1996, Late Quaternary Paleoceanography of the North Atlantic Margins, 7

10.1016/S0377-8398(03)00075-6

10.1016/0277-3791(93)90012-B

Koç N., 1996, Late Quaternary Paleoceanography of the North Atlantic Margins, 177

10.1111/j.1751-8369.2002.tb00085.x

10.1029/92PA01651

10.2307/1551746

Korsun S. A., 1989, Distribution of benthic foraminiferal morphogroups in the Barents Sea, Oceanology, Engl. Transl., 29, 838

Korsun S. A., 1995, Recent foraminifera in glaciomarine sediments from three Arctic fjords of Novaja Zemlija and Svalbard, Polar Res., 14, 15, 10.3402/polar.v14i1.6648

10.1029/94JC02838

10.1016/0921-8181(95)00011-9

10.1016/S0277-3791(97)00066-8

10.1111/j.1502-3885.1996.tb00838.x

10.1016/S0277-3791(01)00016-6

10.2113/gsjfr.18.1.16

10.1016/S0277-3791(01)00088-9

10.1029/95JC01251

10.1016/0377-8398(84)90018-5

Nagy J., 1965, Foraminifera in some bottom samples from shallow waters in Vestspitsbergen, Aarb. Nor. Polarinst., 1963, 109

10.1029/1999PA000411

10.1029/GM085p0077

Polyak L., 1996, Late Quaternary Paleoceanography of the North Atlantic Margins, 323

Polyak L., 1994, Late‐ and postglacial environments in the northern Barents Sea, west of Franz Josef Land, Polar Res., 13, 197, 10.3402/polar.v13i2.6693

10.1016/0967-0637(93)90071-A

10.1130/0091-7613(1996)024<0937:CCITFS>2.3.CO;2

10.1029/96PA02618

Rudels B.(1987) On the mass balance of the Polar Ocean with the emphasis on the Fram Strait Skr. Nor. Polarinst.188 53 pp.

10.1016/S0967-0645(99)00015-6

10.2113/32.3.217

10.1029/2000JC000478

10.1080/002919502760056350

Salvigsen O., 1992, Thermophilous molluscs on Svalbard during the Holocene and their palaeoclimatic implications, Polar Res., 11, 1, 10.1111/j.1751-8369.1992.tb00407.x

10.1111/j.1502-3885.2003.tb01227.x

10.1029/2003JC001823

10.1023/A:1005504031923

10.1016/0033-5894(73)90052-5

10.1016/0012-821X(83)90162-0

Solheim A. andC. F.Forsberg(1996) Norwegian Polar Institute's cruise to the northern margin of Svalbard and the Barents Sea 25/7–2/9 1994: Marine geology/geophysics and physical oceanography Rep. Ser. 92 Nor. Polarinst. Oslo.

10.1029/98JC00580

Steinsund P. I.(1994) Benthic foraminifera in surface sediments of the Barents and Kara seas: Modern and late Quaternary applications Ph.D. thesis 111 pp. Univ. of Tromsø Tromsø Norway.

10.1177/095968369300300401

10.1017/S0033822200013904

10.1017/S0033822200019123

10.1017/S0033822200019172

10.1007/BF00193533

10.1177/095968369700700105

10.1111/j.1502-3885.1999.tb00217.x

10.1002/(SICI)1099-1530(199907/09)10:3<251::AID-PPP323>3.0.CO;2-5

Vinje T. E., 1977, Sea ice conditions in the European sector of the marginal seas of the Arctic, 1966–75, Aarb. Nor. Polarinst., 1975, 163

10.1016/S0921-8181(01)00111-4

Walton W. R., 1964, Approaches to Paleoecology, 151

10.1016/S0377-8398(98)00007-3

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American Geophysical Union (AGU)

Tập 20 Số 4

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