The European sand belt in eastern Europe -and comparison of Late Glacial dune orientation with GCM simulation results JAAPJAN ZEEBERG BOl EUEAS Zeeberg, J. J. 1998 (June): The European sand belt in eastern Europe -and comparison of Late Glacial dune orientation with GCM simulation results.A compilation is presented of the continuation of the European sand belt, east of Poland. Dune fields encompass most of the aeolian formations in eastern Europe. Supposed sand provenance, dune orientation, and the few available datings suggest initial aeolian activity during cold stages of the Upper-Pleni (= full)glacial and Late Glacial, similar to northwest and central Europe. Dune fomiation was primarily supply controlled. Comparison of dune orientation with Late Glacial surface wind directions simulated by various GCMs permits reconstruction of dune activation with the positioning of (winter) westerlies over glacial deposits during the Oldest Dryas. Final widespread aeolian activity occurred during the Younger Dryas. As compared to the smaller fields toward the centre of deglaciation, aeolian sand deposits of the intermediate and periglacial zone benefited from distinctly longer intervals of accumulation. In the zone of deglaciation, aeolian activity was restricted to relatively isolated basins..laupJun Zeeherg, Dt;Dar.trnent of Eur/h and Environtnenral Sciences (MIC 186), Unitwrsity qf Illinois ar Chicczgo.

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Glacier retreat on north Novaya Zemlya for the past century was documented by registering glacier terminus positions from expedition and topographic maps and remotely sensed images. Recession of tidewater calving glaciers on north Novaya Zemlya in the first half of the twentieth century was relatively rapid (>300 m yr-1), consistent with post-‘Little Ice Age’ warming documented by a 122-year instrumental record from Malye Karmakuly. The glaciers completed 75 to 100% of the net twentieth-century retreat by 1952. Between 1964 and 1993 half of the studied glaciers were stable; the remainder retreated modest distances of <2.5 km. This stability coincides with decreasing average temperatures, especially during the winter, which is counter to model prediction. There is a statistically significant covariance of unfiltered winter and summer temperatures from Novaya Zemlya and a smoothed 88-year record of SSTs in the southern Barents Sea (r>0.75). Elevated SST in the Barents Sea appear to reflect increased advection of warm North Atlantic water associated with a positive North Atlantic Oscillation index (NAO). Winter temperatures are periodically correlated with the NAO (r = 0.75 to 0.9) reflecting repeated penetration of Atlantic cyclones into the Arctic. During the twentieth century, an overall positive glacier mass balance trend at Novaya Zemlya is associated with a positive phase of the NAO, elevated southern Barents Sea SST, and a concomitant increase of winter precipitation. Strong NAOs enhance winter precipitation and (3&ndash;5 yr delayed) summer temperatures on Novaya Zemlya and have a variable effect on Novaya Zemlya glaciers.

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Quaternary glacial stratigraphy and relative sea-level changes reveal at least four expansions of the Kara Sea ice sheet over the Severnaya Zemlya Archipelago at 791N in the Russian Arctic, as indicated from tills interbedded with marine sediments, exposed in stratigraphic superposition, and from raised-beach sequences that occur at altitudes up to 140 m a.s.l. Chronologic control is provided by AMS 14 C, electron-spin resonance, green-stimulated luminescence, and aspartic-acid geochronology. Major glaciations followed by deglaciation and marine inundation occurred during MIS 10-9, MIS 8-7, MIS 6-5e and MIS 5d-3. The MIS 6-5e event, associated with the high marine limit, implies ice-sheet thickness of 42000 m only 200 km from the deep Arctic Ocean, consistent with published evidence of ice grounding at $1000 m water depth in the central Arctic Ocean. Till fabrics and glacial tectonics record repeated expansions of local ice caps exclusively, suggesting wet-based ice cap advance followed by cold-based regional ice-sheet expansion. Local ice caps over highland sites along the perimeter of the shallow Kara Sea, including the Byrranga Mountains, appear to have repeatedly fostered initiation of a large Kara Sea ice sheet, with exception of the Last Glacial Maximum (MIS 2), when Kara Sea ice did not impact Severnaya Zemlya and barely graced northernmost Taymyr Peninsula. r