Rapid and rhythmic ice sheet fluctuations in western Scandinavia 15-40 Kya?a review

Abstract

The onshore record of Middle to Late Weichselian sediments and glacial history in Norway indicates a succession of four major ice advances alternating with rapid, considerable ice recessions and interstadial conditions. During all the glacial advances the ice sheet expanded from onshore/inland positions to the shelf areas. The basis for visualizing these variations in glaciation curves constructed along nine transects from inland to shelf, and for interpretation of the palaeoclimatic history, is the regional Quaternary stratigraphy, more than 300 datings, fossil content and some palaeomagnetic data. The methods applied in recent years for AMS radiocarbon dating of glacial sediments with low organic carbon content have given promising results with respect to accuracy and precision, and the results of such datings were an important tool for our reconstructions and for timing of the ice oscillations. The rapid and rhythmic ice fluctuations, as reconstructed in our new model, have been fairly synchronous in most parts of Norway. Ice advances commenced and culminated at 40, 30‐28, 24‐21 and 18‐15 (14C) Kya. We describe three intervening interstadials from inland sites: Hattfjelldal I, Hattfjelldal II and Trofors. Our stratigraphical record also includes many indications of high, pre‐Holocene, relative sea levels, suggesting a considerable glacioisostatic depression of western Scandinavia during the interstadials. In our glaciation model we suggest that, in addition to precipitation, the mountainous fjord and valley topography, glacial isostasy and relative sea level changes were probably more important for the size of the glacial fluctuations than were air temperature changes.

Pink marine sediments reveal rapid ice melt and Arctic meltwater discharge during Dansgaard–Oeschger warmings

“…New data from Norway [43][44][45] , Sweden and Finland 46,47 indicate that the Scandinavian ice sheet during MIS 3 was more dynamic than previously recognized. The evidence is lacking in temporal ARTICLE resolution, but two rapid advances beyond the coastline of Norway seem well-documented 39,40,43 .…”

“…The evidence is lacking in temporal ARTICLE resolution, but two rapid advances beyond the coastline of Norway seem well-documented 39,40,43 . The first advance is correlated with Greenland interstadial 10 and dated to B41 kyr BP on the GICC05 timescale.…”

Ice‐rafting patterns on the western Svalbard slope 74–0 ka: interplay between ice‐sheet activity, climate and ocean circulation

“…Also, studies of the activity of the Fennoscandian Ice Sheet (Olsen et al . , ; Rørvik et al . ; Mangerud et al .…”

14C‐dated fluctuations of the western flank of the Scandinavian Ice Sheet 45–25 kyr BP compared with Bølling–Younger Dryas fluctuations and Dansgaard–Oeschger events in Greenland

“…In the present study area, the deglaciation proceeded at least some 60 km inland (Larsen & Ward 1992). Samples yielding Ålesund Interstadial ages are found in several places in central south Norway and Sweden (Olsen et al 2002; Ukkonen et al 2007) and accordingly a restricted ice sheet has been proposed (Arnold et al 2002; Olsen et al 2002; Vorren & Mangerud 2008). However, some of the ages were obtained by 14 C dating of bulk sediment samples with extremely low C content, and could therefore be inaccurate.…”