Building the resilience of coastal systems to extreme events: the case of the Metropolitan City of Venice and its lagoon

The significant increases in magnitude and frequency of climate related extreme events are placing considerable economic, logistical, and at times social strains upon coastal systems. Within the BRIDGE project, a scenario-informed multicriteria methodology was designed to integrate qualitative (i.e. local stakeholders’ preferences) and quantitative information (i.e. climate change projections) in a unique framework supporting the enhancement of coastal systems resilience to extreme events. Different group of local stakeholders (e.g. local authorities, civil protection agencies, SMEs, NGOs) were involved to identify critical functions (i.e. coastal systems and processes that are likely to be affected by extreme events) and propose risk management initiatives/measures that can be strategic to enhance overall system resilience under the future climate scenarios, and that they wish to consider for prioritization. Most representative scenarios describing main climatic threats (e.g. storm surges, floods, heatwaves, drought) that could affect coastal areas of interests were selected and represented based on projections of Regional Climate Models for medium term period (e.g. 2021–2050). Multicriteria Decision Analysis (MCDA) was finally used to compare the initiatives and to select the optimal ones across different scenarios, using the set of critical functions and local stakeholders’ perspectives as the basis for the ranking. The methodology was tested in the Metropolitan City of Venice to assess the resilience of proposed risk management projects against the impacts of climate change scenarios envisioned for the area.