Stationarity of monthly rainfall series since the middle of the XIXth century. Application to the case of Peninsular Spain

Based on analysis techniques including homogeneity tests and anomalies and trend analysis, a methodology was developed and applied to nine long monthly rainfall series of Peninsular Spain (1859-1997). On the basis of a previous spatial regionalization, these series are considered to be representative for this area. After studying the main features of their temporal evolution on a regional scale, results have been compared to those procured by other studies within the AMHY/FRIEND project of UNESCO for other Mediterranean regions. The conclusions show that there is no significant trend in the series. On the contrary, a common dry period for the whole of Spain between 1935 and 1955 that coincides with a negative anomaly affecting the Western Mediterranean has been found.