Current measurements over the upper slope off the west coast of Portugal, 1994-1995

Abstract

In an attempt to study the characteristics of the slope current off the Iberian Peninsula, as part of its contribution to the EU funded project SEFOS (Shelf Edge Fisheries and Oceanography Study), the Institute Hidrografico, Lisbon, Portugal, has been carrying out current measurements in the upper 600 m of the water column over the upper continental slope off the west coast of Portugal. At latitude 390 45' N, a clear northward slope current was observable in the upper 300-400 mover 910 m bottom depth, from October 1994 to January 1995, and again in April 1995. The mean monthly signal was baroclinic, with maximum values close to 11 cm s·' around 200 m in October. and 100 m in December 1994. The northward (residual) current reached 35 cm s·, in December 1994. 16 km offshore, over 2300 m bottom depth, the current showed larger cross-slope fluc tuations than over 910 m, except in April 1995, when the current was clearly polarized along the slope at both moorings, with maximum velocity between 100 m and 150 m. This suggests that the core of the current is usually close to (or inshore of) the 900 m isobath, with occasional meanders, as might have happened in April 1995