Early and climatic warning systems for coastal systems. A seamless approach for coastal risk reduction under climate change

Coastal systems are experiencing increasing pressures and degradation due to climatic and anthropic factors, projected to escalate under future scenarios. Such an increase will require more natural and economic resources to maintain coastal zones the way we know them, leading to competing and often incompatible uses for scant fresh water, sand volumes or coastal accommodation space. Without proactive measures, current coastal protection strategies will face exacerbating vulnerabilities, resulting in unsustainable risk levels and compromised ecosystem integrity. Addressing these issues requires innovative, resilient solutions that harness the growing wealth of metocean data and integrate our understanding of the complex interactions between hydrodynamic, morphological, and ecological processes.

The paper introduces a seamless sustainability-focused framework for coastal protection that combines short term predictions (daily scales) for proactive risk mitigation with long term projections (decadal scales) to guide adaptive management strategies before critical tipping points are reached.  The approach emphasizes coordinated interventions across scales and sectors, prioritizing Nature-based-Solutions (NbS), to enhance resilience, while promoting compatibility between protection measures. The proposed “no-regret” solutions are designed and maintained by robust predictions and projections, complemented by practical insights from pilot restorations projects in key coastal ecosystems: seagrass beds, wetlands and vegetated dunes. This unified NbS strategy, implemented across different time scales and coastal seas in Europe, will prove the value of leveraging metocean knowledge to increase coastal resilience under changing climates, controlling the impact, maintenance and extension of NbS.

Aligned with the goals of the UN Decade of Ocean Science for Sustainable Development (2021-2030), the proposed approach contributes to the Ocean Decade's mission of delivering transformative ocean knowledge for sustainable action. By fostering a science-driven framework that integrates early warnings and long-term climatic projections, the system aims to ensure sustainable coastal protection based on healthy, functioning ecosystems that provide essential services in a changing climate. Key services include reduced flooding and erosion risks, improved coastal water quality, enhanced biological productivity, and increased coastal blue carbon sequestration.

The paper presents findings from pilot cases conducted along EU coasts as part of the EU Green Deal REST-COAST project. The results of these restorations showcase the benefits of combining metocean simulations with observational data, leading to more sustainable and lower-carbon footprint interventions. Furthermore, the approach offers scalability and potential application in other regions beyond Europe, particularly in coastal areas that are highly vulnerable to climate impacts. By effectively managing the implementation, maintenance, and extension of NbS, this framework demonstrates how metocean knowledge can be used to enhance coastal resilience globally. From here it offers a shared pathway for a more sustainable and adaptive future for coastal communities.