Origin and Characteristics of the Algerian Current

摘要

Satellite and ship data collected May 1-22, 1986, show that the Algerian Currentoriginates in the Almeria-Oran Front and remains within 30 km of the Algerian coast for over 300 km, between Oran and Algiers. The differences between the water masses of the current and the resident regional waters are clearly observed in the chlorophyll concentrations and optical characteristics, thus permitting the resulting patterns to be used as tracers of the circulation. During this field period, the Algerian Current begins as an extension of the Almeria-Oran Front, which is found at the western periphery of the Eastern Alboran Gyre. This major oceanographic salinity front (Delta S > 1/km) delineates the boundary of the Algerian Current, which has average surface velocities of 40 cm/s and maximum speeds reaching 80 cm/s. The current, which has a volume transport between 0.4 and 0.5 Sv, is confined to the upper 150 m and is in geostrophic balance. A sequence of coastal zone color scanner (CZCS) and advanced very high resolution radiometer (AVHRR) satellite imagery showing the rapidly evolving surface circulation features is augmented with in situ ship data of current and water mass characteristics. Rapid undulations and frontal movements of the current were observed during the study period; however, the flow remained unbroken between 1 deg and 3 deg E. Keywords: Phytoplankton; Chemical oceanography; Ocean currents. Reprints. (edc)