Impact of the ice strength formulation on the performance of a sea ice thickness distribution model in the Arctic. Issue 3 (16th March 2017)

• Record Type: Journal Article
• Authors: Ungermann, Mischa; Tremblay, L. Bruno; Martin, Torge; Losch, Martin
• Is Part Of: Journal of geophysical research. Volume 122:Issue 3(2017)
• Page Start: 2090
• Page End: 2107
• Publication Date: 2017-03-16
• Subjects: cost function -- coupled sea ice‐ocean model -- Arctic -- ice strength parameterization -- MITgcm -- Green's function approach; Oceanography -- Periodicals; 551.4605
• DOI: 10.1002/2016JC012128
• Languages: English
• ISSNs: 2169-9275

Abstract

Abstract: The impact of a subgrid‐scale ice thickness distribution (ITD) and two standard ice strength formulations on simulated Arctic sea ice climate is investigated. To this end, different model configurations with and without an ITD were tuned by minimizing the weighted mean error between the simulated and observed sea ice concentration, thickness, and drift speed with an semiautomatic parameter optimization routine. The standard ITD and ice strength parameterization lead to larger errors when compared to the simple single‐category model with an ice strength parameterization based on the mean ice thickness. Interestingly, the simpler ice strength formulation, which depends linearly on the mean ice thickness, also reduces the model‐observation error when using an ITD. For the ice strength parameterization that makes use of the ITD, the effective ice strength depends strongly on the number of thickness categories, so that introducing more categories can lead to overall thicker ice that is more easily deformed. Key Points: An ice thickness distribution (ITD) model can significantly improve the fit to satellite observations The simple ice strength parameterization of Hibler (1979 ) leads to smaller model errors than the one of Rothrock (1975 ) The ice strength following Rothrock (1975 ) strongly depends on the number of thickness categories