Simulation of the Antarctic ice sheet with a three-dimensional polythermal ice-sheet model, in support of the EPICA project. II. Nested high-resolution treatment of Dronning Maud Land, Antarctica.A. A. SAVVIN, R. GREVE, R. CALOV, B. MÜGGE and K. HUTTER AbstractThe modern dynamic and thermodynamic state of the entire Antarctic ice sheet is computed as the result of a 242200 year paleoclimatic simulation with the 3-d polythermal ice-sheet model SICOPOLIS. The simulation is driven by a climate history derived from the Vostok ice core and the SPECMAP sea-level record. In a 872 x 436 km region in western Dronning Maud Land (DML), where a deep ice core is planned within the frame of the European Project for Ice Coring in Antarctica (EPICA), new high-resolution bedrock and ice-thickness data are implemented and a locally refined numerical grid is applied, which goes beyond the predecessor of this study (Calov et al., Ann. Glaciol., 27, 201-206, 1998). The computed fields of basal temperature, age and shear deformation together with the measured accumulation rates give valuable information for the selection of a suitable drillsite in accordance with the objective to obtain a high-resolution climate record for the last glacial cycle. Based on these results, a possible drillsite at 73°59'S, 00°00'E is discussed, for which the computed depth profiles of temperature, age, velocity and shear deformation are presented. The geographic origin of the ice column at this position extends 1320 km upstream and therefore does not leave the DML region. Annals of Glaciology, 30, 69-75 (2000). |
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