THE IMPACT OF THE NORTH-ATLANTIC OCEAN ON THE YOUNGER-DRYAS CLIMATE IN NORTHWESTERN AND CENTRAL-EUROPE

The main results of multiproxy climate reconstructions for the Younger Dryas and experiments carried out with an atmospheric general circula tion model are discussed. Quantitative temperature inferences for nort hwestern and central Europe show that winter conditions were remarkabl y extreme, with values of 20-30 degrees C below that of today. Annual temperature ranges with a continental signature (30-34 degrees C) were reconstructed for the entire study area. Compared with today, the gre atest cooling was experienced in the seaboard area. The comparison of the climate reconstructions and simulation experiments indicates that sea-ice in the North Atlantic Ocean played a decisive role in the clim ate of the study area by cooling the surface air temperatures and by c ontrolling the position of the storm track. Surface air circulation wa s westerly even during Younger Dryas winters. A slight northward shift of the mean Atlantic sea-ice margin during winter may explain the pro posed subdivision of the Younger Drays into a phase of maximum cold an d humidity succeeded by a less cold and relatively dry phase. (C) 1998 John Wiley & Sons, Ltd.