| Popis: |
Oceanographic observations have shown the existence of a large anticyclonic gyre in the western Alboran Sea. Satellite imagery demonstrates the persistence of the Alboran Gyre and suggests that the direction of inflow through the Strait of Gibraltar plays an important role in determining the size and location of the gyre. Satellite data also reveals more time varying, smaller scale circulation patterns in the eastern Alboran Sea. The reduced gravity model of Hurlburt and Thompson (1980, J. Phys. Oceanogr. 10: 1611-1651) has been adapted to the semi-enclosed basin of the Alboran Sea. The model domain is a rectangle 600 km east-west by 160 km north-south. The Strait of Gibraltar is modeled by a port in the western boundary and the eastern boundary is entirely open. When the model is forced by a northeastward inflow through the port in the western boundary, it evolves to a steady state which exhibits a meandering eastward current. The first meander of this current forms the northern boundary of a strong anticyclonic gyre in the western part of the basin. The dimensions and location of the model gyre are consistent with the persistent gyre observed to dominate the western Alboran Sea. A weaker cyclonic circulation in the eastern Alboran is also predicted by the model. This model solution closely resembles the observational data of Lanoix (1974, NATO Tech. Report 66, Brussels). The solution was obtained without including bottom topography, coastline features, or winds which have been suggested as important factors in determining the size and location of the Alboran Gyre. A preliminary investigation using the model indicates the importance of inflow angle, inflow vorticity, and the location of the Strait of Gibraltar. This model does not account for the variability observed in the circulation of the eastern Alboran Sea. |
