FN Archimer Export Format PT J TI Centennial-scale variability of the British Ice Sheet: Implications for climate forcing and Atlantic meridional overturning circulation during the last deglaciation BT AF KNUTZ, Paul C. ZAHN, Rainer HALL, Ian R. AS 1:1;2:2,3;3:4; FF 1:;2:;3:; C1 Univ Copenhagen, Inst Geol, Copenhagen, Denmark. Univ Autonoma Barcelona, Inst Ciencia & Tecnol Ambientals, E-08193 Bellaterra, Spain. Inst Catalan Rec & Estudis Avancats, E-08193 Bellaterra, Spain. Cardiff Univ, Sch Earth Ocean & Planetary Sci, Cardiff CF710 3YE, Wales. C2 UNIV COPENHAGEN, DENMARK UNIV AUTONOMA BARCELONA, SPAIN INST CATALAN REC & ESTUDIS AVANCATS, SPAIN UNIV CARDIFF, UK IF 3.391 TC 64 UR https://archimer.ifremer.fr/doc/00233/34437/32940.pdf LA English DT Article CR IMAGES 1-MD101 MD 122 / WEPAMA BO Marion Dufresne DE ;ice sheet variability;rapid climate change;North Atlantic overturning circulation AB Evidence from paleoclimatic archives suggests that Earth's climate experienced rapid temperature changes associated with pronounced interhemispheric asymmetry during the last glacial period. Explanations for these climate excursions have converged on nonlinear interactions between ice sheets and the ocean's thermohaline circulation, but the driving mechanism remains to be identified. Here we use multidecadal marine records of faunal, oxygen isotope, and sediment proxies from the northeast Atlantic proximal to the western margins of the last glacial British Ice Sheet (BIS) to document the coupling between ice sheet dynamics, ocean circulation, and insolation changes. The core data reveal successions of short-lived (80-100 years), high-amplitude ice-rafted debris (IRD) events that were initiated up to 2000 years before the deposition of detrital carbonate during Heinrich events (HE) 1 and 2. Progressive disintegration of the BIS 19-16 kyr before present (B.P.) occurred in response to abrupt ocean-climate warmings that impinged on the northeast Atlantic during the early deglaciation. Peak IRD deposition recurs at 180-220 year intervals plausibly involving repeated breakup of glacial tidewater margins and fringing marine ice shelves. The early deglaciation culminated in a major meltwater pulse at similar to 16.3 kyr B. P. followed by another discharge associated with HE1 some 300 years after. We conclude that temperature changes related to external forcing and marine heat transport caused a rapid response of the BIS and possibly other margins of the Eurasian Ice Sheet. Massive but short-lived meltwater surges influenced the Atlantic meridional overturning circulation thereby contributing to North Atlantic climate variability and bipolar climatic asymmetry. PY 2007 PD FEB SO Paleoceanography SN 0883-8305 PU Amer Geophysical Union VL 22 IS 1/PA1207 UT 000244376600001 BP 1 EP 14 DI 10.1029/2006PA001298 ID 34437 ER EF