The shallow shelf approximation as a 'sliding law' in a thermomechanically coupled ice sheet model

Autor: Bueler, Ed, Brown, Jed
Rok vydání: 2008
Předmět:
Zdroj: J. Geophys. Res. 114, F03008, 2009
Druh dokumentu: Working Paper
DOI: 10.1029/2008JF001179
Popis: The shallow shelf approximation is a better ``sliding law'' for ice sheet modeling than those sliding laws in which basal velocity is a function of driving stress. The shallow shelf approximation as formulated by \emph{Schoof} [2006a] is well-suited to this use. Our new thermomechanically coupled sliding scheme is based on a plasticity assumption about the strength of the saturated till underlying the ice sheet in which the till yield stress is given by a Mohr-Coulomb formula using a modeled pore water pressure. Using this scheme, our prognostic whole ice sheet model has convincing ice streams. Driving stress is balanced in part by membrane stresses, the model is computable at high spatial resolution in parallel, it is stable with respect to parameter changes, and it produces surface velocities seen in actual ice streams.
Comment: 12 pages of text; 4 tables; 27 figures; submitted to JGR Earth Surface
Databáze: arXiv