Résumé
This study aims at defining a method for selecting an optimal interpolated climatic dataset in the context of an integrated modelling of the Ebro (85 000 km(2), Spain) hydro-system. Two different sets of temperature and precipitation were chosen according to data availability criteria, and each set was interpolated on an 8 x 8 km grid covering the basin, with and without a monthly or annual altitudinal gradient applied by geographical area (Pyrenees, Cantabrian and Iberian ranges) over 1000 m a.m.s.l. Seven basins (464 to 2975 km(2)) representing different flow regimes of the Ebro catchment were chosen to evaluate the performance of 24 different climatic datasets for modelling water resources. We used a conceptual model (GR4j) at a daily time step to test the sensitivity of hydrological modelling to the different sets of precipitation and temperature. A global score was attributed to each dataset according to the different hydrological modelling criteria in order to discriminate the best-performing dataset.