There are no sequential and integrated approaches that include the steps needed to perform an adequate management and planning of the coastal zones to mitigate coastal erosion problems and climate change effects. Important numerical model packs are available for users, but often looking deeply to the physical processes, demanding big computational efforts and focusing on specific problems. Thus, it is important to provide adequate tools to the decision-makers, which can be easily interpreted by populations, promoting discussions of optimal intervention scenarios in medium to long-term horizons. COMASO (coastal management software) intends to fill this gap, presenting a group of tools that can be applied in standalone mode, or in a sequential order. The first tool should map the coastal erosion vulnerability and risk, also including the climate change effects, defining a hierarchy of priorities where coastal defense interventions should be performed, or limiting/constraining some land uses or activities. In the locations identified as priorities, a more detailed analysis should consider the application of shoreline and cross-shore evolution models (second tool), allowing discussing intervention scenarios, in medium to long-term horizons. After the defined scenarios, the design of the intervention should be discussed, both in case of being a hard coastal structure or an artificial nourishment (third type of tools). Finally, a cost-benefit assessment tool should optimize the decisions, forecasting costs and benefits for each different scenario, through definition of economic values to the interventions and to the land/services/ecosystems, weighting all the environmental, cultural, social and historical aspects. It is considered that COMASO tools can help giving answers to the major problems of the coastal planning and management entities, integrating transversal knowledge in risk assessment, physical processes, engineering and economic evaluations. The integrated coastal zone management needs these tools to ensure sustainable coastal zones, mitigating erosion and climate change effects.

Worldwide, artificial nourishments are being considered as one of the main coastal erosion mitigation measures. However, this solution is not permanent, since the natural removal of sediments that occurs after the sand deposition leads to the need of re-nourishment projects; thus, its performance and longevity dependent on several design parameters (placement site and extension alongshore, frequency, and volume, etc.) In this work, a methodological approach for cost–benefit assessment is applied to analyze the performance of artificial nourishments from a physical and economical point of view, by analyzing the effectiveness of different scenarios. The study was developed considering two study areas: a hypothetical situation (generic study area) and a real coastal stretch (Barra-Vagueira, located in the Portuguese west coast). The findings show the complexity in defining the best nourishment option, being dependent on the wave climate, site specific conditions, and main goal of the intervention. The proposed cost–benefit approach allows one to obtain and compare the physical and economic performance of artificial nourishments to mitigate coastal erosion, aiding the decision-making processes related to coastal planning and management.

Coastal dunes, formed and shaped by aeolian sediment transport, play a crucial role in ecosystem services and act as natural flood and coastal erosion defenses. This paper delves into theoretical equations and numerical models predicting sediment transport. Numerical models like cellular automata, XBeach-DUNA, the coastal dune model, and others are analyzed for their ability to simulate dune morphology, erosion processes, and vegetation impacts accurately. Evaluated are field observation and measurement techniques, such as sand traps, impact sensors, and optical sensors, for their precision in quantifying aeolian dynamics. Further examined is the effectiveness of vegetation and fencing in dune stabilization, noting species-specific responses and the influence of fence design on sediment accumulation. These tools offer insights into optimizing aeolian sediment management for coastal protection. By conducting a systematic review and connecting theoretical, empirical, and modeling findings, this study highlights the complex challenge of measuring and managing aeolian sediment transport and proposes integrated strategies for enhancing coastal dune resilience against the backdrop of climate change and erosion. This study’s objectives to bridge gaps in current understanding are met, highlighting the need for a multidisciplinary approach to coastal dune management and conservation, especially combining wind- and wave-driven processes.

This work aims to provide a more complete characterization of coastal erosion mitigation and climate change adaptation measures by presenting a participatory approach that integrates medium- to long-term perspectives, considering simultaneously social, environmental, economic and engineering dimensions to help decision makers implement sustainable climate change adaptation (CCA) strategies. The work lists, explains and characterizes existing climate change mitigation and adaptation measures as well as their costs and positive and negative social, environmental and economic impacts, in three distinct databases. These databases are discussed, complemented and validated in participatory moments with local stakeholders of the Ovar Municipality, Portugal, which represents the case study to support the proposed methodology. Although Ovar is a pilot case, the integrated framework for resilient CCA has a global application with respect to methodologies and concepts. The proposed approach is useful to help coastal management entities to engage in more efficient, effective and beneficial planned action to mitigate coastal erosion and adapt to future climate change effects. The open-source databases and the participatory approach facilitate decision makers and coastal communities to navigate the complexity of solutions and build consensus around collective actions for coastal areas.