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Relative sea-level (RSL) data provide constraints on land uplift associated with former ice loading and can be used to differentiate between contrasting ice unloading scenarios. Isolation basin, coastal lowland and geomorphological evidence is employed to reconstruct RSL changes in northwest (NW) Iceland, which may have experienced contrasting uplift patterns. Under local (NW) uplift, highest RSL would be expected in central Vestfirðir, whereas highest RSL would be closest to the main ice-loading centre under regional (central Iceland) uplift. Four new RSL records are presented based on 16 sea-level index points and 4 limiting ages from sites principally focussed along a transect away from central Iceland. The new RSL records highlight spatial variability of Holocene RSL changes and provide constraints on deglaciation. There is an increase in marine limit elevation with proximity to the proposed principal ice loading centre in central Iceland. Highest recorded marine limit shorelines are found in Hrútafjörður-Heggstaðanes (southeast), the lowest in Hlöðuvík and Rekavík bak Látrum (north), and at an intermediate elevation in Reykjanes-Laugardalur (central Vestfirðir). Evidence from Breiðavik-Látrar records early rapid deglaciation in Breiðafjörður or a complex interplay of multiple uplift centres. RSL fell rapidly following deglaciation in several locations as a result of the quick response of the Icelandic lithosphere to unloading. The RSL data along the transect show an uplift pattern consistent with extensive regional glaciation emanating from central Iceland, which could have implications for ice sheet configuration and patterns of deglaciation, glacio-isostatic adjustment modelling and the volume of meltwater input into the North Atlantic. [ABSTRACT FROM AUTHOR]

Foraminiferal assemblages and the sedimentology of two cores (POR20 and POR21) from eastern Disko Bugt, west Greenland, are used to identify environmental changes in the area over the past c. 2200 years. Changes in the sediment flux supplied to the core sites from Jakobshavn Isbrae are used to assess the relative position of the calving margin. An Atlantic water influence as strong as, or slightly stronger than, present prevailed at c. 2200?cal. yr BP. A trend of increasing Atlantic water influence then culminated in peak warm and saline hydrographic conditions c. 1664–474?cal. yr BP encompassing the ‘Medieval Warm Period’. This period was marked by a retreat of the calving front of Jakobshavn Isbrae and was followed by a marked cooling in hydrographic conditions relating to an increase in the influence of the East Greenland Current in the West Greenland Current corresponding to the climatic episode the ‘Little Ice Age’. A rise in sedimentation rate over this period relates to the well-documented advance of Jakobshavn Isbrae. The record from Disko Bugt shows good agreement with the temperature record from the Greenland ice cores and other climatic and oceanographic reconstructions in the region. [ABSTRACT FROM AUTHOR]

The relatively fresh and cold East Greenland Current (EGC) connects the Arctic with the subpolar North Atlantic Ocean. Its strength and influence on the freshwater balance in the North Atlantic affects both the Subpolar Gyre dynamics and deep convection in the Labrador Sea. Enhanced freshwater and sea-ice expansion in the subpolar North Atlantic is suggested to modify the northward heat transport within the North Atlantic Current. High-resolution palaeoceanographic reconstructions, based on planktic and benthic foraminifera assemblage data, from the central East Greenland shelf (Foster Bugt) reveal distinct centennial to millennial-scale oceanographic variability that relates to climatic changes during the mid to late Holocene (the last c. 6.3 ka BP). Our data highlight intervals of cooling and freshening of the polar surface EGC waters that accompany warming in the subsurface Atlantic waters, which are a combination of chilled Atlantic Intermediate Water (AIW) from the Arctic Ocean and of the Return Atlantic Current (RAC) from the West Spitsbergen Current (WSC). Mid Holocene thermal optimum conditions prevailed until c. 4.5 ka BP. A thin/absent surface Polar Water layer, low drift/sea-ice occurrence and strong contribution of recirculating warm Atlantic waters at the subsurface, suggest a relatively weak EGC during this period. Subsequently, between 1.4 and 4.5 ka BP, the water column became well stratified as the surface Polar Water layer thickened and cooled, indicating a strong EGC. This EGC strengthening parallelled enhanced subsurface chilled AIW contribution from the Arctic Ocean after c. 4.5 ka BP, which culminated from 1.4 to 2.3 ka BP. This coincides with warming identified in earlier work of the North Atlantic Current, the Irminger Current, and the West Greenland Current. We link the enhanced contribution of chilled Atlantic Water during this period to the time of the ‘Roman Warm Period’. The observed warming offshore East Greenland, centred at c. 1.8 ka BP, likely occurred in response to changes in the interactions of i) a weakened Subpolar Gyre; ii) increased northward heat advection in the North Atlantic Current, and iii) a predominant positive North Atlantic and Arctic Oscillation mode, prevailing during the time of the Roman Warm Period. [ABSTRACT FROM AUTHOR]