Surface currents off the west coast of Ireland studied from satellite images

Publisher Website
Google Scholar
Abstract
The surface current in the spring of 1984 off the west coast of Ireland has been mapped from NOAA-8 thermal infrared images. The “feature-tracking method” has been used to derive flow vectors from advective sea surface temperature feature displacements and elapsed time. This feature-tracking method has a great advantage which gives a synoptic and spatial view of the velocity distribution over in situ measurements. Sequential images obtained on orbits 5596, 5610 and 5627 during the period 25-27 April 1984 have been used and geometrically corrected. With the 24 hours and 48 hours differences, the measurement accuracy achieved in the speed of sea features was ±1 8cm/s. The surface current pattern agrees with the main current pattern obtained by ships and drift bottles. A cyclonic eddy centred at 57° 04′ N 10° 59′ W has been studied. A very pronounced feature recognized is the sea surface front between mixed coastal water and stratified Atlantic water along the whole west coast of Ireland. The front is characterized by cyclonic and anticyclonic eddies which have time scales of the order of 1 day to 7 days and length scales of the order of 30 km.