HR: 0800h
AN: C11B-0439    [Abstracts]
TI: Scaling properties of the Arctic sea ice Deformation from Buoy Dispersion Analysis
AU: Weiss, J
EM: weiss@lgge.obs.ujf-grenoble.fr
AF: LGGE-CNRS, 54 rue moliere, Saint Martin d'heres, 38402, France
AU: * Rampal, P
EM: prampal@lgge.obs.ujf-grenoble.fr
AF: LGGE-CNRS, 54 rue moliere, Saint Martin d'heres, 38402, France
AU: Marsan, D
EM: david.marsan@univ-savoie.fr
AF: LGIT, Universite de Savoie, Le Bourget du Lac, 73376, France
AU: Lindsay, R
EM: lindsay@apl.washington.edu
AF: Polar Science Center Applied physics laboratory, 1013 NE 40th Street, Seattle, WA 98105, United States
AU: Stern, H
EM: harry@apl.washington.edu
AF: Polar Science Center Applied physics laboratory, 1013 NE 40th Street, Seattle, WA 98105, United States
AB: A temporal and spatial scaling analysis of Arctic sea ice deformation is performed over time scales from 3 hours to 3 months and over spatial scales from 300 m to 300 km. The deformation is derived from the dispersion of pairs of drifting buoys, using the IABP (International Arctic Buoy Program) buoy data sets. This study characterizes the deformation of a very large solid plate -the Arctic sea ice cover- stressed by heterogeneous forcing terms like winds and ocean currents. It shows that the sea ice deformation rate depends on the scales of observation following specific space and time scaling laws. These scaling properties share similarities with those observed for turbulent fluids, especially for the ocean and the atmosphere. However, in our case, the time scaling exponent depends on the spatial scale, and the spatial exponent on the temporal scale, which implies a time/space coupling. An analysis of the exponent values shows that Arctic sea ice deformation is very heterogeneous and intermittent whatever the scales, i.e. it cannot be considered as viscous-like, even at very large time and/or spatial scales. Instead, it suggests a deformation accommodated by a multi-scale fracturing/faulting processes.
DE: 0750 Sea ice (4540)
DE: 0774 Dynamics
DE: 0798 Modeling
SC: Cryosphere [C]
MN: 2007 Fall Meeting