Physically based and spatially distributed, the model called CRHyME (Climatic Rainfall Hydrogeological Modeling Experiment) represents an extension of the classic models that simulate inflows-outflows at the basin scale. The main innovations introduced in 2021 are:
▪ direct interfacing with climate model outputs (e.g., precipitation and temperature data in NetCDF format);
▪ physical description of some hydrogeological instability phenomena strongly linked to precipitation, such as shallow landslides, debris flows, erosion of river basins, and solid transportation.
The CRHyME model is designed to be part of a hydrological modeling chain; its objective is to attempt both a reconstruction and a modeling of the effects of future climate evolution on the local territory, providing a physically based tool for analysis at the basin scale. The CRHyME model relies on the Python programing language and uses the PCRaster libraries. It takes inspiration from the PCR-GLOWB2 model implemented on a global scale to study the effects of climate change on the availability of water resources. The CRHyME model, however, was developed to work at a higher spatial resolution and enable the assessment of hydrogeological risks using available global databases for modeling spatial characteristics at the chosen scale of analysis.
Thanks to the versatility of the CRHyME model, different simulation time-steps can be set and extreme precipitation events reproduced. Using the information obtained from the local curves indicating rainfall possibilities to set the model so as to reproduce the river basin behavior in the event of critical rainfall makes CRHyME also suitable for assessments in the Civil Protection field.
The CRHyME model is still under development. Promising results have been obtained for the case studies of the Valtellina basin in the Alpine region (Lombardy, Italy) and of three Apennine basins (Emilia, Italy). CRHyME has been applied considering three different climate models from the EURO-CODEX program. The results showed a general increase in the intensity of the geo-hydrological cycle, in particular throughout the Alpine region, confirming the results of the studies conducted by the IPCC in relation to the state of the climate, documented in the Sixth Assessment Report (AR6).