Current structure off the North Spanish coast observed by HF radar

The objective of the European Radar Ocean Sensing (EuroROSE) project is to develop a radar based ocean monitoring system in support of safe navigation in port approach areas and otherwise densely operated sea areas. Radar measured data are assimilated into a fine gridded numerical model with the aim of predicting, for a few hours, currents and waves. A demonstration of this system was carried out off the North Spanish coast from October to November 2000. The area selected covers the approach to the harbour of Gijon. Two HF radars WERA (Wellen Radar) of the University of Hamburg were deployed. WERA, operated at 27.65 MHz, measures surface currents within an area of about 40 by 40 km with a spatial resolution of about 1 km and with a temporal sampling of 20 min. The Spanish measurement network consists of different types of wave bouys. Currents have not been recorded in the area under consideration. For the first time, the maps of surface current, acquired during the EuroROSE Gijon experiment, show the high spatial and temporal variability off the North Spanish coast. This paper presents first experimental results with emphasis on the dynamics of the coastal current. Depending on the wind situation, up to two coastal jets with a chain of eddies in between has been observed.