WATERMED project contributes to the international efforts in analyzing efficiency in water use, in particular for the Mediterranean Basin countries. The general aim of this project is to develop a comprehensive method for the study of the water use and the resistance to the drought of the natural and irrigated vegetation in the Mediterranean Basin, by means of a combined historical remote sensing database, vegetation models and field measurements. The project has provided regional maps of critical parameters at regional scale, such as land surface temperature, emissivity, and NDVI. A multi-temporal analysis using the PATHFINDER AVHRR land data has been carried out into the frame of this project to map and monitor changes in the biophysical characteristics of land cover over the last 20 years. On the other hand, REANALYSIS data, which is a result of a joint project NCEP/NCAR, have been incorporated to provide mean monthly climate data over the study area.