FN Archimer Export Format PT J TI Dansgaard-Oeschger cycles: Interactions between ocean and sea ice intrinsic to the Nordic seas BT AF DOKKEN, Trond M. NISANCIOGLU, Kerim H. LI, Camille BATTISTI, David S. KISSEL, Catherine AS 1:1,2;2:1,2,3;3:2,4;4:2,5;5:6; FF 1:;2:;3:;4:;5:; C1 UNI Res AS, Bergen, Norway. Bjerknes Ctr Climate Res, Bergen, Norway. Univ Bergen, Dept Earth Sci, N-5007 Bergen, Norway. Univ Bergen, Inst Geophys, N-5007 Bergen, Norway. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. UVSQ, CNRS, CEA, Lab Sci Climat & Envionnement, Gif Sur Yvette, France. C2 UNI RES BERGEN, NORWAY BCCR, NORWAY UNIV BERGEN, NORWAY UNIV BERGEN, NORWAY UNIV WASHINGTON, USA UNIV VERSAILLES, FRANCE IF 3.918 TC 142 UR https://archimer.ifremer.fr/doc/00264/37490/35779.pdf LA English DT Article CR IMAGES V LEG 1-MD114 IMAGES V LEG 4-MD114 BO Marion Dufresne DE ;D-O cycles;Nordic seas;marine sediment core;Greenland ice core;abrupt changes;sea ice AB Dansgaard-Oeschger (D-O) cycles are the most dramatic, frequent, and wide-reaching abrupt climate changes in the geologic record. On Greenland, D-O cycles are characterized by an abrupt warming of 105 degrees C from a cold stadial to a warm interstadial phase, followed by gradual cooling before a rapid return to stadial conditions. The mechanisms responsible for these millennial cycles are not fully understood but are widely thought to involve abrupt changes in Atlantic Meridional Overturning Circulation due to freshwater perturbations. Here we present a new, high-resolution multiproxy marine sediment core monitoring changes in the warm Atlantic inflow to the Nordic seas as well as in local sea ice cover and influx of ice-rafted debris. In contrast to previous studies, the freshwater input is found to be coincident with warm interstadials on Greenland and has a Fennoscandian rather than Laurentide source. Furthermore, the data suggest a different thermohaline structure for the Nordic seas during cold stadials in which relatively warm Atlantic water circulates beneath a fresh surface layer and the presence of sea ice is inferred from benthic oxygen isotopes. This implies a delicate balance between the warm subsurface Atlantic water and fresh surface layer, with the possibility of abrupt changes in sea ice cover, and suggests a novel mechanism for the abrupt D-O events observed in Greenland ice cores. PY 2013 PD SEP SO Paleoceanography SN 0883-8305 PU Amer Geophysical Union VL 28 IS 3 UT 000325628700010 BP 491 EP 502 DI 10.1002/palo.20042 ID 37490 ER EF