Southern Ocean sea-ice simulations forced with operationally derived atmospheric analyses data

• Main Author: Stössel, A.
• Format: Report
• Language: English
• Published: Max-Planck-Institut für Meteorologie 1991
• Subjects: Southern Ocean; Sea ice
• Online Access: http://hdl.handle.net/21.11116/0000-0000-E5B3-3; http://hdl.handle.net/21.11116/0000-0000-E5B5-1

As a supplement to an earlier paper on a coupled sea—ice — oceanic mixed-layer [SI — OML] model for the Southern Ocean (Stössel et al.‚ 1990), the atmospheric forcing in this investigation is changed from monthly (climatological) data to daily (instantaneous) values. These data are derived from global analyses from the European Center for Medium Range Weather Forecasts (ECMWF). With these computations applied as surface forcing, results similar to the earlier ones are achieved. Adjustments of the SI-model parameters and/or the coefficients of the bulk formulas can be avoided when the forcing is raised to its originally assigned level, using an appropriate Prandtl—layer parameterization. With this extension, the model results are well comparable with observations based on operationally produced ice charts. A further rise of the atmospheric forcing to the geostrophic level by means of coupling a one—dimensional atmospheric boundary—layer [ABL] model to the SI — OML model, reduces the dependency of the results on the (climatologically) prescribed boundary conditions of the operational numerical weather- prediction [NWP] model. The simulations with this extension, however, appear to be reasonable only when the surface wind pattern is applied, the roughness length over ice and water is increased, and the stability of the ABL over ice is generally reduced.