Bayesian Network Analysis for Shoreline Dynamics, Coastal Water Quality, and Their Related Risks in the Venice Littoral Zone, Italy

Abstract

The coastal environment is vulnerable to natural hazards and human-induced stressors. The assessment and management of coastal risks have become a challenging task, due to many environmental and socio-economic risk factors together with the complex interactions that might arise through natural and human-induced pressures. This work evaluates the combined effect of climate-related stressors on low-lying coastal areas by applying a multi-risk scenario analysis through a Bayesian Network (BN) approach for the Venice coast. Based on the available open-source and remote sensing data for detecting shoreline changes, the developed BN model was trained and validated with oceanographic variables for the 2015–2019 timeframe, allowing us to understand the dynamics of local-scale shoreline erosion and related water quality parameters. Three “what-if” scenarios were carried out to analyze the relationships between oceanographic boundary conditions, shoreline evolution, and water quality parameters. The results demonstrate that changes in sea surface height and significant wave height may significantly increase the probability of high-erosion and high-accretion states. Moreover, by altering the wave direction, the water quality variables show significant changes in the higher-risk class. The outcome of this study allowed us to identify current and future coastal risk scenarios, supporting local authorities in developing adaptation plans.

Coastal Adaptation Pathways and Tipping Points for Typical Mediterranean Beaches Under Future Scenarios

“…A sequential adaptation with a multirisk assessment [26] enables a flexible set of interventions to enhance coastal resilience, avoid TPs and, in the approach here proposed, demonstrating the shared benefits of nature-based solutions (NbS) or living shorelines. The developed dynamic adaptation plans [27] consider climate and management evolution, proposing a set of actionable interventions and estimating their contribution to risk reduction in terms of key and robust physical parameters, simpler to project than ecologic or socioeconomic ones.…”

Coastal Adaptation Pathways and Tipping Points for Typical Mediterranean Beaches under Future Scenarios

“…Such consensus and the convergence of stakeholder criteria are based on an explicit assessment of synergies and tradeoffs for the proposed coastal interventions, including estimations of costs, impacts and carbon footprint. Based on the proposed dynamic adaptation plans and risk assessments [28][29][30], the actionable interventions can be assessed and ranked according to risk reduction, estimated as a function of key physical parameters that integrate the complex social-ecological dynamics of the coastal system.…”