FN Archimer Export Format PT J TI Warming of surface waters in the mid-latitude North Atlantic during Heinrich events BT AF NAAFS, B. D. A. HEFTER, J. GRUTZNER, J. STEIN, R. AS 1:1;2:1;3:1;4:1; FF 1:;2:;3:;4:; C1 Department of Marine Geology and Paleontology, Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany. C2 INST A WEGENER, GERMANY IF 3.918 TC 55 UR https://archimer.ifremer.fr/doc/00262/37305/35717.pdf LA English DT Article CR IMAGES V LEG 1-MD114 IMAGES V LEG 4-MD114 BO Marion Dufresne AB During the six Heinrich events of the last 70 kyr, episodic calving from the circum-Atlantic ice sheets released large numbers of icebergs into the North Atlantic. These icebergs and associated meltwater flux are hypothesized to have led to a shutdown of Atlantic Meridional Overturning Circulation and severe cooling in large parts of the Northern Hemisphere. However, due to the limited availability of high-resolution records, the magnitude of sea surface temperature (SST) changes related to the impact of Heinrich events on the midlatitude North Atlantic is poorly constrained. Here we present a record of U-37(K)-based SSTs derived from sediments of Integrated Ocean Drilling Project Site U1313, located at the southern end of the ice-rafted debris (IRD) belt in the midlatitude North Atlantic (41 degrees N). We demonstrate that all six Heinrich events are associated with a rapid warming of surface waters by 2-4 degrees C in a few thousand years. The presence of IRD leaves no doubt about the simultaneous timing and correlation between rapid surface water warming and Heinrich events. We argue that this warming in the midlatitude North Atlantic is related to a northward expansion of the subtropical gyre during Heinrich events. As a wide range of studies demonstrated that in the central IRD belt Heinrich events are associated with low SSTs, these results thus identify an antiphased (seesaw) pattern in SSTs during Heinrich events between the midlatitude (warm) and northern North Atlantic (cold). This highlights the complex response of surface water characteristics in the North Atlantic to Heinrich events that is poorly reproduced by freshwater hosing experiments and challenges the widely accepted view that, within the IRD belt of the North Atlantic, Heinrich events coincide with periods of low SSTs. PY 2013 SO Paleoceanography SN 0883-8305 PU American Geophysical Union VL 28 IS 1 UT 000317838200014 BP 153 EP 163 DI 10.1029/2012PA002354 ID 37305 ER EF