43 research outputs found
Variations in mineralogical composition of dust present in the Greenland SIGMA-D ice core and EGRIP snow pit over the past 100 years
The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Thu. 5 Dec. / 2F Auditorium , National Institute of Polar Researc
Investigation of the ice nucleation properties of dust collected in northwest Greenland
第6回極域科学シンポジウム[OM] 極域気水圏11月16日(月) 統計数理研究所 セミナー室2(D304
Spatial distribution of cryoconite granules and microorganisms on Qaanaaq Glacier, Greenland
第6回極域科学シンポジウム分野横断セッション:[IB2] 地球環境変動の解析と地球生命システム学の構築11月19日(木) 統計数理研究所 セミナー室1(D305
Spatial variation of surface mass balance and seasonal variation of dust deposition at EGRIP, Greenland
The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Wed. 4 Dec. / Entrance Hall (1st floor) , National Institute of Polar Researc
Seasonal variations of snow chemistry at EGRIP, Greenland
The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Thu. 5 Dec. / 2F Auditorium , National Institute of Polar Researc
Location, morphology and size distribution of solid particles in an ice core retrieved from NEEM, Greenland
The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Thu. 5 Dec. / 2F Auditorium , National Institute of Polar Researc
Microbial composition changes in cryoconite formation process in Northwestern Greenland
第3回極域科学シンポジウム/特別セッション「これからの北極研究」11月28日(水) 国立極地研究所 2階大会議
Microstructural analysis of the NEEM ice core, Greenland by using electron backscatter diffraction (EBSD)
Mass loss of the Greenland ice sheet is accelerating, which is attributed to increased ice stream discharge and changes in surface mass balance including increased runoff. Ice stream discharge is caused by both ice deformation and basal sliding. For better projection of future mass loss, it is important to understand deformation mechanisms of polycrystalline ice in ice sheet. Deformation properties of polycrystalline material are related to its microstructure (e.g. crystal grain orientation and size). As recrystallization and recovery are occurring together in ice sheet, analysis of microstructure of ice is essential. Electron backscatter diffraction (EBSD) is a method for measuring crystal lattice orientation with high angular and spatial resolutions. Both c- and a-axes of ice can be measured. We analyzed Greenland NEEM ice core and the preliminary result shows that most subgrain boundaries (SGBs) observed by optical microscopy have lattice misorientations < 4°. This result is in accordance with analyses of Antarctic EDML ice core by X-ray diffractometry while it differs from threshold angle of SGB/GB estimated with a dislocation theory. The observation results from ice sheet ice could contribute to better estimations of strain rate by models based on microstructural processes