Simulation of fast-flow features of the Fennoscandian ice sheet during the Last Glacial Maximum

• Published in: Annals of Glaciology
• Main Authors: Forsström, Pirjo-Leena, Sallasmaa, Olli, Greve, Ralf, Zwinger, Thomas
• Format: Article in Journal/Newspaper
• Language: English
• Published: International Glaciological Society
• Subjects: Fennoscandian ice sheet; Scandinavian ice sheet; Last Glacial Maximum; Fast flow; Ice stream; 452; Greenland; Kara Sea; Taymyr; Annals of Glaciology; Fennoscandia; Fennoscandian; GRIP; Ice Sheet; Taymyr Peninsula
• Online Access: http://hdl.handle.net/2115/34574; https://doi.org/10.3189/172756403781815500

In order to reconstruct the palaeoglaciation in Fennoscandia and northern Asia during the late-Weichselian ice-age phase, simulations with the dynamic and thermodynamic ice-sheet model SICOPOLIS are carried out. Our focus is on the Last Glacial Maximum (LGM) around 20 kyr BP. Climate forcing is based on mean annual surface temperature and precipitation derived from present data and Palaeoclimatic Modelling Intercomparison Project (PMIP) UKMO21 results for the LGM. These distributions are interpolated via a glacial index defined by the Greenland Icecore Project (GRIP) δ18 O record. The extent of the Scandinavian and the Barents ice sheets is reproduced in good agreement with the Quaternary Environments of the Eurasian North (QUEEN) reconstruction, but the Kara Sea and Taymyr Peninsula areas are excessively glaciated. The fast-flow regions derived from the simulations, which are generally connected to regions with a temperate base and temperate ice above, are compared to hypothesized palaeoice-stream locations, especially in the Norwegian Channel and the Baltic area. In the Norwegian Channel, temperate basal conditions with temperate ice above prevail and favour fast flow. In the Baltic area, ice-sheet advance is generally accompanied by slow ice velocities (<200 m a-1). Some temporary fast-flow features occur due to transitional temperate-base conditions, and higher velocities arise in retreat phases.