FN Archimer Export Format
PT J
TI A highly unstable Holocene climate in the subpolar North Atlantic: evidence from diatoms
BT 
AF ANDERSEN, C
   KOC, N
   MOROS, M
AS 1:1,2;2:1;3:3;
FF 1:;2:;3:;
C1 Norwegian Polar Res Inst, N-9296 Tromso, Norway.
   Univ Bergen, Dept Earth Sci, N-5007 Bergen, Norway.
   Bjerknes Ctr Climate Res, N-5007 Bergen, Norway.
C2 NORWEGIAN POLAR RES INST, NORWAY
   UNIV BERGEN, NORWAY
   BCCR, NORWAY
IF 3.323
TC 116
UR https://archimer.ifremer.fr/doc/00229/34003/32348.pdf
LA English
DT Article
CR IMAGES 1-MD101
BO Marion Dufresne
AB A composite record (LO09-14) of three sediment cores from the subpolar North Atlantic (Reykjanes Ridge) was investigated in order to assess surface ocean variability during the last 11 kyr. The core site is today partly under the influence of the Irminger Current (IC), a branch of the North Atlantic Drift continuing northwestward around Iceland. However, it is also proximal to the Sub-Arctic Front (SAF) that may cause extra dynamic hydrographic conditions. We used statistical methods applied to the fossil assemblages of diatoms to reconstruct quantitative sea surface temperatures (SSTs). Our investigations give evidence for different regional signatures of Holocene surface oceanographic changes in the North Atlantic. Core LO09-14 reveal relatively low and highly variable SSTs during the early Holocene, indicating a weak IC and increased advection of subpolar water over the site. A mid-Holocene thermal optimum with a strong IC occurs from 7.5 to 5 kyr and is followed by cooler and more stable late Holocene surface conditions. Several intervals throughout the Holocene are dominated by the diatom species Rhizosolenia borealis, which we suggest indicates proximity to a strongly defined convergence front, most likely the SAF. Several coolings, reflecting southeastward advection of cold and ice-bearing waters, occur at 10.4, 9.8, 8.3, 7.9, 6.4, 4.7, 4.3 and 2.8 kyr. The cooling events recorded in the LO09-14 SSTs correlate well with both other surface records from the area and the NADW reductions observed at ODP Site 980 indicating a surface-deepwater linkage through the Holocene.
PY 2004
PD NOV
SO Quaternary Science Reviews
SN 0277-3791
PU Pergamon-elsevier Science Ltd
VL 23
IS 20-22
UT 000224648200009
BP 2155
EP 2166
DI 10.1016/j.quascirev.2004.08.004
ID 34003
ER

EF