Interannual winter temperature variability in the north of the Iberian Peninsula

This work analyses the interannual variability of winter temperature in the north of the Iberian Peninsula, This area exhibits a different behaviour t o the rest of the Iberian Peninsula, according to the loading factors of th e leading empirical orthogonal function of Iberian winter temperature and p recipitation. The regional time series is defined by means of principal com ponents analysis (PCA) as a data reduction tool. The only significant eigen value can be related to synoptic causes. It is linked, for signals with a p eriod lower than 10 yr, to the East Atlantic teleconnection pattern. It doe s not show any significant correlation to the North Atlanic Oscillation (NA O) or Arctic Oscillation (AO), which are the major factors controlling temp erature over European or Iberian areas. This result agrees with previously published works and can be explained on the basis of enthalpy transport den sity vectors and geopotential anomaly over the area. Eddy terms do not play a significant role in this relationship. The link of the interannual varia bility of temperature in the area with the Atlantic sea surface temperature (SST) is also analysed, but SSTs do not show any significant predictive sk ill, and the statistically significant relationship does not seem to be cau sal.