High spatial and temporal resolution precipitation over Mediterranean basin for Digital Twin Earth Hydrology and 4dMED projects

The Mediterranean basin is a complex environment characterized by both exceptional biodiversity and intense human presence. This environment is already highly influenced by the anthropogenic activities, but their importance is expected to rise up due to the forecasted increase of population (from 480 million people to 520-570 million by 2030) and ongoing climate change. These conditions will trigger an increase of human pressures, including urbanization, industrialization, the expansion of intensive agriculture activities (i.e., irrigation) and aquaculture, thus threatening the natural resources availability, and specifically the water availability. Droughts, floods and landslides events are already stepping up in this environment, making it urgent to develop models systems capable to predict the extreme complex and widespread climate variations of this area.

ESA recognized the crucial role of this region by funding the Digital Twin Earth (DTE) Hydrology Evolution and the 4dMED projects, specifically dedicated to reconstruct the Mediterranean terrestrial water cycle at 1km spatial and 1 day temporal resolution and to develop a prototype of Digital Twin for the entire Mediterranean basin, which can be used for the prediction of hydrological extremes, the management of the water resource cycle and the simulation of the changes that the system may undergo. To reach those objectives, the latest developments of Earth Observation (EO) data as those derived from the ESA-Copernicus missions will be exploited together with in situ observations, hydrological and hydraulic models, artificial intelligence tools and advanced digital platform functionalities.

Among the hydrologic variables datasets generated within these projects, precipitation holds a major role due to its influence on the natural hazards occurrence. Here, we show the procedure adopted to generate the high spatial and temporal resolution precipitation product over the Mediterranean region by downscaling and merging different satellite and in-situ precipitation products. The obtained dataset is evaluated against high resolution observed data in several region of the Mediterranean basin, in order to assess its performance with respect to others EO derived precipitation datasets.