Abstract: Observational gridded products are commonly used to evaluate the performance of regional climate models. To this aim, gridded dataset should be comparable with the output of these models and, thus, should represent grid-cell area-averaged values and, whenever possible, should use the same simulation domains of the models in order to avoid re-gridding or re-projection. In this study we present an update of the Spain02 gridded observational dataset for daily precipitation and mean temperature building on the grids defined for the Euro-CORDEX initiative.
In order to assess and intercompare different interpolation approaches, we analyzed 1) two standard methodologies (ordinary kriging and thin plate splines), 2) three horizontal resolutions: 0.11º , 0.22º and 0.44º (matching the rotated Euro-CORDEX and ENSEMBLES grids), 3) two different approaches to guarantee either area-averaged or point representativity of the resulting grid values and 4) including/excluding orography as a co-variable in the interpolation procedure. Besides of introducing the new set of gridded datasets, in this work we also present some preliminary results on the sensitivity of temperature and precipitation (both mean and extreme regimes) to all these factors.
