Ridging, strength, and stability in high‐resolution sea ice models
Loading...
Authors
Lipscomb, William H.
Hunke, Elizabeth C.
Maslowski, Wieslaw
Jakacki, Jaromir
Subjects
Advisors
Date of Issue
2007
Date
2007
Publisher
American Geophysical Union
Language
Abstract
In multicategory sea ice models the compressive strength of the ice pack is often
assumed to be a function of the potential energy of pressure ridges. This assumption,
combined with other standard features of ridging schemes, allows the ice strength to
change dramatically on short timescales. In high-resolution (~10 km) sea ice models with
a typical time step (~1 hour), abrupt strength changes can lead to large internal stress
gradients that destabilize the flow. The unstable flow is characterized by large oscillations
in ice concentration, thickness, strength, velocity, and strain rates. Straightforward,
physically motivated changes in the ridging scheme can reduce the likelihood of abrupt
strength changes and improve stability. In simple test problems with flow toward and
around topography, stability is significantly enhanced by eliminating the threshold fraction
G* in the ridging participation function. Use of an exponential participation function
increases the maximum stable time step at 10-km resolution from less than 30 min to
about 2 hours. Modifying the redistribution function to build thinner ridges modestly
improves stability and also gives better agreement between modeled and observed
thickness distributions. Allowing the ice strength to increase linearly with the mean ice
thickness improves stability but probably underestimates the maximum stresses.
Type
Article
Description
The article of record as published may be found at http://dx.doi.org/10.1029/2005JC003355
Series/Report No
Department
Oceanography
Organization
Naval Postgraduate School (U.S.)
Identifiers
NPS Report Number
Sponsors
Climate Change Prediction Program (CCPP) and the Scientific Discovery through Advanced Computing (SciDAC) program of the U.S. Department of Energy’s Office of Science
Shelf-Basin Interaction (SBI) program of the U.S. National Science Foundation
CCPP and through the International Arctic Research Center’s Arctic Ocean Model Intercomparison Project (AOMIP)
Arctic Region Supercomputing Center (ARSC) through the U.S. Department of Defense High Performance Computer Modernization Program (HPCMP)
Shelf-Basin Interaction (SBI) program of the U.S. National Science Foundation
CCPP and through the International Arctic Research Center’s Arctic Ocean Model Intercomparison Project (AOMIP)
Arctic Region Supercomputing Center (ARSC) through the U.S. Department of Defense High Performance Computer Modernization Program (HPCMP)
Funder
Format
18 P.
Citation
Lipscomb, W. H., E. C. Hunke, W. Maslowski, and J. Jakacki (2007), Ridging, strength, and stability in high-resolution sea
ice models, J. Geophys. Res., 112, C03S91.
Distribution Statement
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.