Multi-risk assessment within the context of climate change in mountain regions

Mountain regions are facing multiple impacts due to climate change and anthropogenic activities. While shifts in precipitation and temperature are affecting the available water, current water demand for economic activities still rely on large quantity of water making mountain regions particularly susceptible to water scarcity. This conditions call for innovative methodologies able to represent complex dynamics of human-natural systems to understand and adapt to future climate change impacts. For these reasons, a literature review considered five innovative modelling approaches (Bayesian networks, agent-based models, system dynamic models, event and fault trees, and hybrid models), exploring their advantages and limitations and providing a roadmap for methodological and technical implementation of multi-risk assessments. Among these methodologies, system dynamics modelling (SDM) was chosen and applied to explore multiple interactions and feedback loops associated to hydrological processes and human demands in the Noce river catchment in the Province of Trento (Italy). Firstly, this study explored the vulnerability of a major reservoir in the Noce catchment considering the current situation and future climate change effects influencing the water stored and flow diverted to reservoir hydropower turbines and the amount of water remaining for other activities. By doing so, the aim was to test and demonstrate a probabilistic SDM assessment expanding the information coming from a hydrological model for quick and effective considerations on reservoir future conditions. Secondly, the SDM model was extended to different parts of the overall Noce catchment characterizing the hydropower water demand from other reservoirs, the agriculture demand for apples production and domestic water demand. By doing so, the aim was to compare the available water in future climate change scenarios with the water demand, resulting in vulnerable future conditions and multiple impacts on the selected sectors. Finally, such assessment aimed to identify critical states coming from a systemic perspective of water availability and water demand for each sub-catchment. The study discussed possible adaptation measures aimed to inform decision makers in order to prepare to future conditions of tackle climate-related water scarcity.