Numerical reconstructions of LGM climate across the Eurasian Arctic

Although limits of the Eurasian Ice Sheet at the Last Glacial Maximum (LGM) are known relatively well from geological evidence, the palaeoclimate coex istent with this ice sheet has yet to be identified confidently. A simple i ce-sheet model has been used to determine LGM climate conditions by finding the ice-sheet mass-balance configuration that permits model results to mat ch with geological data relating to the extent of LGM ice cover. These cond itions are compared with Atmospheric General Circulation Model (AGCM) calcu lations of the climate at the LGM, which reveal the meteorological conditio ns associated with the ice-sheet mass-balance. The western margin of Scandi navia is characterised by a maritime climate, influenced by the nearby warm , seasonally sea-ice free, ocean conditions. However, further east, the war ming effect of the North Atlantic diminishes and an extreme polar desert cl imate dominates across the Kara Sea similar to East Antarctica today. The L GM climate that we establish is in contrast to many previous reconstruction s involving snow-laden warm westerly winds originating from the North Atlan tic affecting the entire Eurasian Arctic. Severely cold conditions across t he Eurasian Arctic are compatible with a stable circulation cell over the K ara Sea that isolates the region climatically, and/or cold dry westerly win ds from the Fennoscandian Ice Sheet that flow across the rest of the Eurasi an Arctic. (C) 2001 Elsevier Science Ltd. All rights reserved.