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This paper presents a summary of the evidence for climatic changes during the last glacial-interglacial transition (14-9 ka BP) in land areas adjacent to the North Atlantic. It is a synthesis of the results of the 12 regional summaries compiled by contributors to the North Atlantic Seaboard Programme of IGCP-253 that are published separately in this issue of journal of Quaternary Science. Eighteen palaeotemperature curves are compared and arranged in three transects, one from southern Europe to Spitsbergen, a second from Ireland to Poland, and the third from southern New England to the Labrador-Baffin Shelf area. Ten maps are presented that summarise the synoptic climatic conditions of the region in 500-year time periods. The purpose of the exercise is to examine the extent to which any emerging patterns support the Ruddiman and Mclntyre model of large-scale shifts in the position of the oceanic Polar Front during the last glacial-interglacial transition. Some broad agreement emerges, although the influence of oceanic changes is diminished in areas that lay in close proximity to the Laurentide and Fennoscandian ice sheets. Attention i s drawn to limitations in the compilations and to the potential for improved models in the future. Journal of Quaternary Science UNE

On the Îles de la Madeleine, a rock platform as much as 20 m asl, locally with clam borings, is correlated to the regional interglacial surface at 2–8 m; its anomalous height may be a consequence of salt tectonics. Overlying lagoonal and paludal organic beds, one with Th/U ages of 89–101 ka, record the Sangamonian climatic optimum (substage 5e), which culminated in forest more thermophilous than that of the Holocene optimum. Overlying littoral gravel and sand, considered analogous to sediments in present-day tombolos, and organic beds with less temperate pollen types were deposited during the marine transgressive climax of substage 5e and thus indicate that sea level remained high after the thermal optimum, as in Holocene time. Cold-based Early Wisconsinan ice, probably centred on the Magdalen Shelf, tectonized bedrock and interglacial beds and deposited till upon them. Periglacial features indicate a subsequent long cold period. An organic bed dating from 11.3 to 10.6 ka records a warm interval followed by cooling. Buried peat, a submerged fossil sea cliff, and barrier beaches record a marine transgression during the late Holocene.

Lake sediment cores from two lakes yielded pollen profiles which reflect vegetational and climatic changes since deglaciation. Radiocarbon dates from specific levels outline the chronology. Correlation of pollen zones between the two profiles indicate the degree of error in the anomalously old dates from one of the sites. Total absolute pollen frequencies are used to aid in interpretation.Following deglaciation a tundra environment prevailed until about 12 000 radiocarbon years B.P. This was followed by a transition zone in which Betula and Populus were abundant. About 12 000 years B.P. Picea increased markedly and remained a dominant part of the vegetation until 9500 years B.P. when Pinus and Quercus became prominent. Tsuga and various hardwood genera predominated after 6500 years B.P. An increase in Picea and decline in Tsuga and some hardwood genera produced the forests which prevailed when the area was settled.