Wind variability in a coastal area (Alfacs Bay, Ebro River delta)

Abstract. Wind spatial heterogeneity in a coastal area (Alfacs Bay, northwestern Mediterranean Sea) is described using a set of observations and modelling results. Observations in three meteorological stations (during 2012–2013) along the coastline reveal that wind from the N–NW (strongest winds in the region) appears to be affected by the local orography promoting high wind variability on relatively short spatial scales (of the order of few kilometres). On the other hand, sea breezes in late spring and summer also show noticeable differences in both spatial distribution and duration. The importance of wind models' spatial resolution is also assessed, revealing that high resolution (= 3 km) substantially improves the results in comparison to coarse resolution (9 km). The highest-resolution model tested (400 m) also presents noticeable improvements during some events, showing spatial variability not revealed by coarser models. All these models are used to describe and understand the spatial variability of the typical wind events in the region. The results presented in this contribution should be considered on hydrodynamic, ecological and risk management investigations in coastal areas with complex orography.