Influence of the NAO on the northwestern Mediterranean wave climate

This study examines teleconnections between the North Atlantic Oscillation (NAO) and the wave climate of the northwestern Mediterranean Sea (NWN,1), defined by the monthly mean significant wave height (SWH and the 95(th) percentile significant wave height (95(th) percentile SWH), in the period ranging from 1958 to 2001. The data analyzed comes from the multidecadul hindcast over Europe carried out during the HIPOCAS project. In order to avoid fictitious cross-correlations, data were prewhitened by fitting a p-order autoregressive model. To split the temporal and spatial variability. an EOF encoding technique was applied to residuals before searching for teleconnections. We found the northwestern Mediterranean wave climate to be influenced by the North Atlantic Oscillation (NAO) with an instantaneous response. When the NAO is in its positive phase, positive anomalies in the SWH and the 95(th) percentile SWH appear in the area between the Balearic Islands, the Gulf of Lions and the Catalonian coast.