Sensitivity of a global sea ice model to the treatment of ice thermodynamics and dynamics

• Main Authors: Fichefet, Thierry, Morales Maqueda, M.A.
• Other Authors: UCL - SST/ELI/ELIC - Earth & Climate
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 1997
• Subjects: dynamics; global model; sea ice; sensitivity; thermodynamics; CISM : CECI; 1443; Antarctic; Arctic; The Antarctic; Antarc*; Sea ice
• Online Access: http://hdl.handle.net/2078.1/129428

The sensitivity of a global thermodynamic-dynamic sea ice model coupled to a one-dimensional upper ocean model to degradations of the model physics is investigated. A single set of parameter values is employed to simultaneously simulate the Arctic and Antarctic ice regimes. A control run carried out with the model demonstrates that it does reasonably well in simulating the seasonal waxing and waning of both ice packs. The sensitivity study focuses on physical processes pertaining to (1) the vertical growth and decay of sea ice, (2) the lateral growth and decay of sea ice, and (3) the sea ice dynamics. A total of nine sensitivity experiments have been performed. It appears that the thermal inertia of the snow-ice system is negligible in the Antarctic but not in the Arctic. It is also found that the inclusion of a prognostic snow layer and of a scheme of snow ice formation is important for sea ice modeling in the Southern Hemisphere. Furthermore, results suggest that the thermodynamic effect of the subgrid-scale snow and ice thickness distributions, the existence of open water areas within the ice cover, and the ice motion play a crucial role in determining the seasonal behavior of both ice packs.