Study of the impact of a new Drag Coefficient parameterization on the forecasting skill of an Ocean Model in the Aegean and Levantine Seas
Abstract
The aim of this work is to study the response of an ocean circulation model in the Eastern Mediterranean Sea, using a new drag coefficient formula based on observations at this area. Thirty twin simulation experiments of 5-days, using two different drag coefficient parameterizations were carried out by the Aegean-Levantine Eddy Resolving Model in a forecasting mode, covering all seasons and different wind field patterns for the year 2013. The new formula’s forcing is based on measurements over the Aegean Sea while the second one is currently used by the model. The results show that the sea surface circulation was enhanced using the new parameterization giving wind stress values greater about 30%. The forecasting skill of the model was tested by comparing the daily sea surface temperature averaged estimations using the two formulas, with satellite observation records. Significant differences were found between the two formula’s forecasts, both in space and in time, over the Aegean Sea and over the areas of the Levantine basin. Improved SST forecasts were found during spring over the Aegean Sea, while during autumn and winter, the differences were almost negligible. At summer, the bias was increased with undesired effects regarding SST forecasts, close to the coastal regions of the Eastern Mediterranean Sea that favor coastal upwelling.ÂReferences
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