SPATIAL AND TEMPORAL PATTERNS OF ANNUAL PRECIPITATION VARIABILITY OVER THE IBERIAN PENINSULA

In this study we have examined the spatial and temporal variability of the annual precipitation observations over the Iberian Peninsula (IP) for 47 years and 51 stations. Empirical orthogonal functions (EGFs) w ere obtained in order to characterise the variability. Four regional p recipitation regimes have been identified and the corresponding princi pal components (PCs) were subjected to spectral analysis in order to o btain the structure of the temporal variations. The relationship betwe en the precipitation and circulation patterns is also investigated. Th e four leading PCs of annual precipitation are associated with the fol lowing patterns: East Atlantic (EA); North Atlantic Oscillation (NAG); Southern Oscillation Index (SOI); Scandinavia (SCAND). The spectra of the precipitation PCs show statistically significant oscillations coh erent with those found in the time series of the teleconnection indice s. A reconstruction of the time series as a function of the PCs is pro vided in order to obtain a characterisation of precipitation climatolo gy over the IP. (C) 1998 Royal Meteorological Society.