Spatial and temporal study of rainfall trends in a Mediterranean landscape (Region of Valencia, SE, Spain)

Abstract

We analysed temporal and spatial trends in rainfall volume and concentration from 96 pluviometric stations in the Region of Valencia (E. Spain) from 1961 to 1990. The main results of analysis are the following: 1) We find a decrease in annual rainfall in 43% of the stations studied. Variability in rainfall volume remains unchanged or increase (52% and 38% of the stations respectively). 2) Monthly rainfall concentration shows no temporal trend in 41% of the stations and a gradual increase in 39% of the stations. Similar figures are obtained for variability in rainfall concentration. 3) In areas with low average rainfall (semiarid climate), annual rainfall volume increases or remain unchanged, whereas, in are as with high average precipitation (dry to subhumid climate) a negative trend dominate. 4) We discuss results in relation to predictions from GCM studies and to the origin of the rainfall events.