Climatologia della precipitazione sull’Europa e il Mediterraneo da osservazioni e modelli climatici (1979-2016)

Precipitation is one of the elements of the hydrological cycle that influences the environment and life on Earth. It is closely linked to the dynamics of the Earth's ecosystems, which have their inherent variability but are also strongly influenced by human activity, and therefore it is a variable that is difficult to estimate. The European continent and the Mediterranean Basin are a rich and heterogeneous ecosystem and represent one of the planet's climate hotspots, i.e. one of the area most sensitive to climate change. The objective of this work the study of the climatology and variability of precipitation over Europe and the Mediterranean from high-resolution observations from ground stations, satellites and climate models for a period ranging between 1979 and 2016. In addition to the rain gauge precipitation measurements provided by the E-OBS, the data from the Multi-Source Weighted Ensemble Precipitation product (MSWEP), that is a merging of precipitation estimates from reanalysis, rain gauges, and microwave and infrared satellite sensors, and data from climate modeling output from the EURO-CORDEX project. Thus, comparisons were made among the three products and for each one, the precipitation index time series at annual and monthly scales were calculated using the ClimPACT2 software. Then, the climatology of the indices was calculated, and, through a cluster analysis, the large area analyzed was divided into sub-areas. This subdivision was useful to enable the computation of the monthly rainfall trend for each cluster and thus detect the presence of a seasonal rain cycle depending on the geographical sub-area, latitude, longitude, and orography. Furthermore, the presence of any annual trend in the indices was evaluated using the Mann-Kendall Trend Test. The results of the significant trends were then localized within the clusters and compared with the trend of the average annual anomalies.