Spatial and temporal patterns of precipitation in Spain for the period 1880–1992

Abstract

Abstract 10.1002/(SICI)1097-0088(19981130)18:14<1557::AID-JOC328>3.3.CO;2-A The longest series of precipitation records in Spain are analysed using the principal component analysis (PCA) method. EOF analysis was used to spatially summarise the rainfall data and to enable clarification of the role of the dominant circulation regimes affecting the region. Three significant EOFs have been obtained in general, except for summer, when four EOFs are found. The first EOF is associated with Andalusia and the Spanish interior, the second and third EOFs with the Mediterranean and Cantabric coasts, alternatively, depending on the season. The analysis of the principal components series using a moving average and the Mann–Kendall test, shows significant long term decreases in precipitation for the Mediterranean and interior regions (at least in some seasons), and an increase in precipitation for the Northern coastal region. More of these changes can be related to variations in the large scale circulation features over Western Europe and North Atlantic. The results are also compared with GCM outputs. © 1998 Royal Meteorological Society