|Thesis abstract: |
Climate change is considered as one of the major forces that will affect water availability in the future. Identifying possible response strategies is a complex task because future projections are deeply uncertain and hydro-climatic conditions are expected to evolve gradually in the next decades. Current water management practices may not be robust enough to cope with the climate change impacts on water supply, flood control, agriculture, energy and ecosystems. Methods and tools to assist water resource planners and decision makers are thus required. In this thesis we assess how current and novel, adaptive approaches to water resource management can be used to cope with uncertain and nonstationary hydro-climatic conditions. We discuss the two mainstream approaches to assess climate change impact and to design adaptation strategies, i.e., the scenario-based approach and the vulnerability-based approach. We explore more in depth the vulnerability-based approach, which, in our opinion, is the most promising way to tackle the problems related to the sustainability of the water uses. To this end, we use modelling and optimization tools to explore vulnerabilities and adaptive capacities of water systems and to produce knowledge that is relevant in the decision making context. In particular, we integrate the simulation models usually employed to estimate the impacts of climate change on water resources by considering water-value models, decision models, and multi-objective optimization techniques which allow to describe the complex interactions between social, economic, and environmental aspects. The main contributions of the thesis can be summarized in the following points: i) we exploit simulation and optimization techniques to re-frame the institutional setting where reservoirs are operated, demonstrating that a shift toward a more cooperative and flexible setting can increase the overall efficiency of water resource management and can improve the resilience to unforeseen events, ii) we propose an impact assessment procedure to assess the ability of water resource management practices to compensate future water stresses as projected by climate models, iii) we present tools to assess the inherent adaptation capacity of water system to hydro-climatic changes which, on the one hand, allow to gain a deeper knowledge of the water system characteristics, and, on the other hand, can drive the identification of the most promising adaptation measures to further enhance the adaptation potential of water systems; iv) we address the topic of trend detection in environmental time series combining novel and traditional tools in order to simultaneously tackle the issue of seasonality and interannual variability, which usually characterize natural processes; v) we use stochastic recursive control and model predictive control to test if adaptive management is a viable adaptation measure to climate change. Models and optimization techniques are tested on real-world case studies to discuss their potential and limitations.