2024-03-29T01:57:24Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/296592022-11-17T02:08:08Zhdl_2115_20056hdl_2115_147Simulation of large-scale ice-sheet surges: The ISMIP HEINO experiments1000090374644Greve, RalfTakahama, RyojiCalov, Reinhardopen access国立極地研究所. 本文データは国立極地研究所の許諾に基づきCiNiiから複製したものである.ice sheetHeinrich eventinstabilitysurgemodel intercomparison452.96The three-dimensional, dynamic/thermodynamic ice-sheet model SICOPOLIS (SImulation COde for POLythermal Ice Sheets) is applied to the ISMIP HEINO (Ice Sheet Model Intercomparison Project-Heinrich Event INtercOmparison) set-up. ISMIP HEINO has been designed to study large-scale ice-sheet instabilities, similar to those of the Laurentide ice sheet which are likely the cause of Heinrich events, on a simplified geometry which consists of a flat square with 4000 km side length. This square contains an area which resembles Hudson Bay and Hudson Strait, on which rapid sediment sliding can occur. The ice sheet is built up over 200 ka by assuming a temporally constant glacial climate. For the standard set-up of ISMIP HEINO, we obtain an oscillatory behaviour of the ice sheet with a main period of approx. 7.5 ka. One cycle consists of a gradual growth phase, followed by a massive surge through "Hudson Bay" and "Hudson Strait" owing to rapid sediment sliding on a molten bed. The occurrence of internal oscillations is robust against moderate variations of the surface boundary conditions and the strength of the sediment sliding. These findings support the idea of a free oscillatory mechanism as the main cause for large-scale ice-sheet surges.National Institute of Polar Research2006-11engjournal articleVoRhttp://hdl.handle.net/2115/29659http://ci.nii.ac.jp/naid/1100053280051100053280051344-3437Polar meteorology and glaciology20115https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/29659/1/PMG20-1.pdfapplication/pdf1.17 MB2006-11