Liquid freshwater transport estimates from the East Greenland Current based on continuous measurements north of Denmark Strait

被引:31
作者
de Steur, L. [1 ,2 ]
Pickart, R. S. [3 ]
Macrander, A. [4 ]
Vage, K. [5 ,6 ]
Harden, B. [3 ]
Jonsson, S. [4 ,7 ]
Osterhus, S. [8 ]
Valdimarsson, H. [4 ]
机构
[1] Norwegian Polar Res Inst, Tromso, Norway
[2] Royal Netherlands Inst Sea Res NIOZ, Den Burg, Netherlands
[3] Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA
[4] Marine Res Inst, Reykjavik, Iceland
[5] Univ Bergen, Inst Geophys, Bergen, Norway
[6] Bjerknes Ctr Climate Res, Bergen, Norway
[7] Univ Akureyri, Sch Business & Sci, Akureyri, Iceland
[8] Uni Res Climate, Bergen, Norway
基金
美国国家科学基金会;
关键词
SEA-ICE; BASIN; SHELF;
D O I
10.1002/2016JC012106
中图分类号
P7 [海洋学];
学科分类号
0707 ;
摘要
Liquid freshwater transports of the shelfbreak East Greenland Current (EGC) and the separated EGC are determined from mooring records from the Kogur section north of Denmark Strait between August 2011 and July 2012. The 11 month mean freshwater transport (FWT), relative to a salinity of 34.8, was 65 +/- 11 mSv to the south. Approximately 70% of this was associated with the shelfbreak EGC and the remaining 30% with the separated EGC. Very large southward FWT ranging from 160 mSv to 120 mSv was observed from September to mid-October 2011 and was foremost due to anomalously low upper-layer salinities. The FWT may, however, be underestimated by approximately 5 mSv due to sampling biases in the upper ocean. The FWT on the Greenland shelf was estimated using additional inshore moorings deployed from 2012 to 2014. While the annual mean ranged from nearly zero during the first year to 18 mSv to the south during the second year, synoptically the FWT on the shelf can be significant. Furthermore, an anomalous event in autumn 2011 caused the shelfbreak EGC to reverse, leading to a large reduction in FWT. This reversed circulation was due to the passage of a large, 100 km wide anticyclone originating upstream from the shelfbreak. The late summer FWT of -131 mSv is 150% larger than earlier estimates based on sections in the late-1990s and early-2000s. This increase is likely the result of enhanced freshwater flux from the Arctic Ocean to the Nordic Seas during the early 2010s.
引用
收藏
页码:93 / 109
页数:17
相关论文
共 37 条
[1]   THE ROLE OF SEA ICE AND OTHER FRESH-WATER IN THE ARCTIC CIRCULATION [J].
AAGAARD, K ;
CARMACK, EC .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 1989, 94 (C10) :14485-14498
[2]   Recent large increases in freshwater fluxes from Greenland into the North Atlantic [J].
Bamber, Jonathan ;
van den Broeke, Michiel ;
Ettema, Janneke ;
Lenaerts, Jan ;
Rignot, Eric .
GEOPHYSICAL RESEARCH LETTERS, 2012, 39
[3]  
Cavalieri D.J., 1996, SEA ICE CONCENTRATIO
[4]   Liquid freshwater transport estimates from the East Greenland Current based on continuous measurements north of Denmark Strait [J].
de Steur, L. ;
Pickart, R. S. ;
Macrander, A. ;
Vage, K. ;
Harden, B. ;
Jonsson, S. ;
Osterhus, S. ;
Valdimarsson, H. .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 2017, 122 (01) :93-109
[5]   Recent changes in the freshwater composition east of Greenland [J].
de Steur, L. ;
Pickart, R. S. ;
Torres, D. J. ;
Valdimarsson, H. .
GEOPHYSICAL RESEARCH LETTERS, 2015, 42 (07) :2326-2332
[6]   Hydrographic changes in the Lincoln Sea in the Arctic Ocean with focus on an upper ocean freshwater anomaly between 2007 and 2010 [J].
de Steur, L. ;
Steele, M. ;
Hansen, E. ;
Morison, J. ;
Polyakov, I. ;
Olsen, S. M. ;
Melling, H. ;
McLaughlin, F. A. ;
Kwok, R. ;
Smethie, W. M., Jr. ;
Schlosser, P. .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 2013, 118 (09) :4699-4715
[7]   Freshwater fluxes in the East Greenland Current: A decade of observations [J].
de Steur, L. ;
Hansen, E. ;
Gerdes, R. ;
Karcher, M. ;
Fahrbach, E. ;
Holfort, J. .
GEOPHYSICAL RESEARCH LETTERS, 2009, 36
[8]   Current estimates of freshwater flux through Arctic and subarctic seas [J].
Dickson, Robert ;
Rudels, Bert ;
Dye, Stephen ;
Karcher, Michael ;
Meincke, Jens ;
Yashayaev, Igor .
PROGRESS IN OCEANOGRAPHY, 2007, 73 (3-4) :210-230
[9]   THE GREAT SALINITY ANOMALY IN THE NORTHERN NORTH-ATLANTIC 1968-1982 [J].
DICKSON, RR ;
MEINCKE, J ;
MALMBERG, SA ;
LEE, AJ .
PROGRESS IN OCEANOGRAPHY, 1988, 20 (02) :103-151
[10]   The freshwater composition of the Fram Strait outflow derived from a decade of tracer measurements [J].
Dodd, Paul A. ;
Rabe, Benjamin ;
Hansen, Edmond ;
Falck, Eva ;
Mackensen, Andreas ;
Rohling, Eelco ;
Stedmon, Colin ;
Kristiansen, Svein .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 2012, 117