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[1] The Svalbard archipelago is located in the high Arctic (76°-80°N) within the northernmost reach of the West Spitsbergen Current, which is the continuation of the North Atlantic Current. In this specific setting close to the Polar Front, even small variations in the current system are expected to give large and distinct signals in paleoceanographic parameters. Thus the Svalbard area is ideal for monitoring the past history of the inflow of Atlantic water to the Arctic Ocean. We have studied sediment core NP94-51 taken outside the mouth of the Hinlopen Strait on the northern Svalbard shelf. The paleoceanographic development of the last deglaciation and the Holocene has been reconstructed using benthic and planktonic foraminifera, oxygen isotopes, and ice-rafted detritus. The results show that the first strong subsurface inflow of Atlantic water to the Arctic Ocean after the Last Glacial Maximum commenced at 12.6 14 C kyr B.P. (circa 15,000 calendar (cal) years B.P.) during the Bølling-Allerød interstadial. During the Younger Dryas, polar conditions prevailed at the surface with extensive sea ice cover, and the inflow of Atlantic-derived water was generally diminished. The inflow of more saline, but still cold Atlantic water was relatively strong during the early Holocene and caused intensified seasonal biological productivity. The Atlantic water inflow declined gradually during the mid-Holocene. Between 4500 and 1100 cal years B.P. the inflow was very weak, and the bottom waters over the northern Svalbard margin were cold and of lower salinity. During the last $1000 years, climatic conditions improved such that the subsurface inflow of Atlantic-derived water increased. However, the surface waters were still cold.

Abstract. A combined record of three cores spanning the last 18 kyr from the northern North Sea is investigated for content of benthic and planktonic foraminifera and stable oxygen isotopes. The paleoenvironmental development through this time period shows an early deglaciation (18-14.4 ka) and the Younger Dryas (12.7-11.5 ka)characterized by arctic/ polar conditions and increased ice rafting in the Norwegian Channel. During the Bolling-Allerod period, warm sea surface temperature (9øC) conditions similar to present conditions are inferred, while bottom waters stayed cold (0-1 øC) with normal salinity. The Bolling-Allerod period is interrupted twice at 13.9-13.6 ka (Older Dryas) and at 13.0-12.8 ka (InterAllerod Cooling Period) by reductions in sea surface temperatures and increased sea ice cover. The beginning of the Holocene period is marked by increases in surface and bottom water temperature. Superimposed on the broad climatic changes through the Holocene, a series of short-lived oscillations in the ocean circulation are recorded. The amplitude of these Holocene events appears larger in the early Holocene (prior to 8 ka) than compared with the remaining part of the Holocene. This amplification can possibly be attributed to a general increased freshwater budget in the North Atlantic at this time during the final stages of the deglaciation of the Laurentide and Scandinavian ice sheets.

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