The sensitivity of a high-resolution pan-Arctic coupled ice-ocean model to atmospheric forcing data
Abstract
Dramatic changes in the Arctic sea ice cover over the past few decades have motivated researches to develop improved tools to advance understanding of the forces driving sea ice and climate variability. One of the optimal tools to study such changes is a numerical model. However, modeling of the Arctic ice-ocean system is challenging, in part because the small baroclinic Rossby radius of deformation O(10km), small scale of sea ice deformations and the need for realistic atmospheric forcing data impose critical constraints on numerical models and their skill. A fine horizontal resolution is needed in the model components and in prescribed forcing to simulate mass, heat and other property fluxes modifying the ocean and cryosphere to resemble the nature. To study some of the mechanisms forcing the Arctic system, a high resolution (eddy-permitting) regional coupled ice-ocean model was developed at the Naval Postgraduate School. The model is forced with reanalyzed atmospheric data and it is used to simulate both ocean and sea ice dynamics and thermodynamics over the past decades. Here we concentrate on analyses and intercomparison of model performance forced with different atmospheric data, including the Common Ocean-ice Reference Experiments (CORE), ERA-15 and ERA-40. Our analyses focus on the decade of ice and ocean results in the 1980s and emphasize differences especially with regard to the Arctic sea ice pack in response to varying atmospheric fields. The main goal of this effort is to address the question of what is the sensitivity of an ice-ocean model to varying atmospheric forcing. The results show a delicate system of interactions and feedbacks in the Arctic. Differences between experiments are substantial, especially in the ice thickness distribution but also in other parameters. A quantitative assessment of the sensitivity of high-resolution ice-ocean model to atmospheric forcing fields is attempted.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFM.C33B0634O
- Keywords:
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- 0545 COMPUTATIONAL GEOPHYSICS / Modeling;
- 0750 CRYOSPHERE / Sea ice;
- 1621 GLOBAL CHANGE / Cryospheric change;
- 4207 OCEANOGRAPHY: GENERAL / Arctic and Antarctic oceanography