HR: 10:40h
AN: C12B-02    [Abstracts]
TI: Observations of Surface Roughness at Several Scales in Jakobshavn Isbrae Drainage Basin, Greenland
AU: * Mayer, H
EM: mayerh@mechanik.tu-darmstadt.de
AF: Institut f. Mechanik, Technische Universitaet Darmstadt, Darmstadt, 64289 Germany
AU: Herzfeld, U C
EM: herzfeld@iceberg.colorado.edu
AF: CIRES, University of Colorado Boulder, Boulder, CO 80309-0449 United States
AB: The ice surface in the region of Jakobshavn Isbrae and its drainage basin exhibits a fascinating wealth and complexity of surface forms, which are the manifestation of glaciologic and environmental morphogenetic processes operating at different scales. The fast-moving Jakobshavns Isbrae stands out in any satellite image by its heavily crevassed surface, with surface provinces that extend kilometers to tens of kilometers and crevasses of 10-100 meters, whereas the ice surface in the surrounding slow-moving ice is characterized by much smaller features such as sastrugi, melt ponds, wind- and ablation ridges and smooth snow, which are equally important in understanding the complexity of a changing environment. The observation of such complexity necessitates different scale-dependent observation methods including field, aerial and satellite data and a definition of surface roughness that allows to capture the spatial complexity of the interface between snow/ice and atmosphere. Analysis methods range from structural geology and continuum mechanics to geostatistical surface characterization and classification. Application to Jakobshavns Isbrae is of particular interest as the ice-stream system has long been considered the prototype of a time-independent system but has lately exhibited dramatic changes.
DE: 3299 General or miscellaneous
DE: 1863 Snow and ice (1827)
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting