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Lithofacies and benthic foraminiferal analyses of two sediment cores (BS1191-K13B and K14) from Nansen Fjord, eastern Greenland, show evidence of changing oceanographic and sea-ice conditions from AD 730 to the present. Radiocarbon dates on foraminifera provide century-scale resolution of events, but the frequency of events between dated levels can be estimated with a resolution of approximately 4 to 9 years per centimetre of core. Unstratified glacial-marine diamicton with a calcareous foraminiferal fauna gives way to interstratified diamicton and mud with a predominantly agglutinated foraminifera. The diamictons represent periods of seasonally open water with strong continuous iceberg rafting. Mud layers were deposited during intervals of prolonged sea-ice cover. The evidence suggests that the climate in the region of Nansen Fjord was warmer and more stable than today during a 'Medieval Warm Period' between c. AD 730 to 1100. Variable climatic conditions with frequent intervals of severe cold characterize a 'Little Ice Age' type interval from c. AD 1630 to 1900. An earlier cold interval culminated c. AD 1370. The record is similar to the 1000-yr-long Icelandic sea-ice record and, to a lesser extent, to the central Greenland Crete ice-core record.

Core B997-328PC is from the landward side of a 100-m-deep basin in Reykjarfjö rdur, a small fjord on the north coast of the northwest peninsula of Iceland. This is an area that can be severely affected by incursions of polar sea-ice but has not suffered marked land erosion during the Settlement period. The core is 422 cm in length and consists principally of finegrained muds with in situ molluscs. Eleven AMS 14 C dates on molluscs indicate a constant sediment accumulation rate of ca. 1 cm 10 yr Ϫ1 for the last 4280 ± 50 yr BP. We measured and derived a variety of proxies for indications of changes in the nearshore environment. These included physical properties and grain size, mass accumulation rates, micropalaeontology (pollen and Foraminifera). Multivariate analysis and constrained clustering were used to define major changes in the proxies. In several parameters the major change in the fjord environment occurred close to 1000 14 C yr ago, thus approximately coincident with the onset of the Settlement of Iceland. Other changes are noted at around 1600 and 3400 14 C yr ago; Betula pollen disappears from the record ca. 1500 yr BP and there are peaks in marine productivity occurring ca. 2 and 3.4 ka. A major decline in carbonate accumulation and a sharp increase in the cold water benthic foraminifer Elphidium excavatum forma clavata 400 yr ago represents the local marine signature of the Little Ice Age. None of the changes in our data can be explained adequately by a simple call to land-use practices and an increase in land to sea transport, but both the pollen and foraminiferal records indicate a decrease and even loss of 'warm' elements in both flora and fauna over the past 4 kyr.

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