A REGIONAL 8200 CAL. YR BP COOLING EVENT IN NORTHWEST EUROPE, INDUCEDBY FINAL STAGES OF THE LAURENTIDE ICE-SHEET DEGLACIATION

The most notable change in delta(18)O in Greenland ice cores during th e Holocene occurs at 8200 cal. yr BP. Here we present a new high-resol ution marine record from the northern North Sea, along with tree-ring data from Germany, which contain evidence of a pronounced temperature drop (>2 degrees C) contemporaneous with that of the Greenland ice-cor e records. The synchronous timing of the cooling event in the Greenlan d ice-cores, marine record and tree-ring data from northwest Europe re flects a regional influence on the North Atlantic ocean-atmospheric sy stem, suggesting a prominent role of the North Atlantic thermohaline c irculation. The operation of the North Atlantic ocean circulation is s ensitive to variation in the freshwater budget, implying that any chan ge in freshwater flux is capable of altering the North Atlantic. circu lation system. We hypothesise minor but long-term freshwater fluxes in the final stages of the deglaciation of the Laurentide ice-sheet as a forcing mechanism. (C) 1998 John Wiley & Sons, Ltd.