CURRENT-METER OBSERVATIONS IN THE ARGENTINE CONTINENTAL-SHELF

The first moored current measurements carried out on the Argentine Con tinental Shelf are presented. In order to explore the mean value and t he main temporal scales of the velocity field, current meter data were collected in a cross-shelf section near 43 degrees S between Septembe r 1991 and August 1992. The records indicate that the mean flow is par allel to the local topography and that its intensity increases towards the shelf-break. The mean flow values seem to be related to the inter action of tidal currents with sea-surface height in the inner shelf an d cross-shelf variations in the mass field in the middle shelf. The hi gh frequency component (periods of less than 30 h) accounts for more t han 80% of the observed kinetic energy. Close to the coast the semidiu rnal component is dominant (possibly due to a resonance process), whil e in the middle shelf the inertial and diurnal components become equal ly important. The very low frequency component (periods longer than 10 days) increases its energy seaward, which suggests that it might be f orced by ocean circulation. The relation between currents in the band 0.5-0.1 cycles per day and the wind measured on the coast is not clear . Copyright (C) 1996 Elsevier Science Ltd