Spatial analysis of the wind field on the western coast of Galicia (NW Spain) from in situ measurements

Abstract

We used wind data measured at six meteorological stations to study their spatial representativity on atmosphere–ocean interactions along the western shelf of Galicia and inside the Ría of Vigo. The correlation as a function of distance and complex empirical orthogonal functions of the wind field were computed, allowing us to divide the region into three sub-domains: the open ocean, the shelf and the Ría of Vigo. Afterwards, wind gradients among stations were computed to determine specific spatial wind features: results showed an expected wind channelling effect inside the Ría of Vigo, but also a zonal onshore negative frictional gradient on the shelf that generates Ekman pumping during upwelling favourable winds. Finally, the Ekman transport estimated from meteorological stations was compared with measured transport from two moorings located inside the Ría of Vigo and on the shelf, and we determined that the meteorological station most representative of the wind field in the shelf is the one installed in a moored buoy on the shelf.