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Percorrer CIMA por Objetivos de Desenvolvimento Sustentável (ODS) "11:Cidades e Comunidades Sustentáveis"
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- Best beaches of the world: a critique of web-based ratingPublication . Oliveira, Elaine Baroni de; Newton, Alice; Botero, Camilo M.This study analyzes the content of internet ratings of beaches to identify the indicators used. The methodology used an exploratory internet survey using the term ‘best beaches’ in five languages. For each site, the ranking method used was extracted and the indicators considered were listed, where applicable. Of the 70 websites analyzed, 47 ranked the beaches (67%) but less than 50% used indicators. The remaining were based on the opinion of the editorial board, personal experience, and users’ perceptions. The most used indicator was the color of water, followed by the color of the sand. These results show that the majority of ‘best beaches’ lists are based on subjective criteria. They are an overview of places that appeal to the person that wrote the page and are not scientifically or analytically based. Even when indicators are considered, these are mostly a reflection of the idea of an idealized beach, crystal blue waters with white or gold sand. The actual quality of the beach, including water quality, carrying capacity, and eco system balance, is not addressed. Although visual attractiveness is a key element for the public, these rankings should incorporate a wider range of indicators to fully assess the quality of a beach.
- Can global datasets be used to predict storm-induced coastal erosion?Publication . Fanti, Valeria; Ferreira, Óscar; Loureiro, CarlosThe scarcity of high-resolution in situ data hampers effective storm impact assessment and the development of early warning systems for coastal bar riers worldwide. This study introduces a novel methodology utilising a SWAN XBeach modelling chain, leveraging global hydrodynamic (WAVERYS and GTSM) and topo-bathymetric (TanDEM-X and ETOPO2022) datasets to perform first-order, globally applicable storm impact assessments for barrier coasts. The approach is validated with high-resolution data from Duck, North Carolina, using pre- and post-storm topographic LiDAR, recorded wave conditions and water levels. The results indicate that global datasets can reasonably reproduce barrier ero sion patterns, despite underestimation of total water levels and dune morphology due to the coarse resolution and inaccuracies in the GTSM and TanDEM-X data. The simulations effectively capture dune retreat and erosion trends, aligning with measured data, but inconsistencies are observed in morphological changes for the upper beach face. These discrepancies are likely due to differences in intertidal elevation and beach face steepness between the LiDAR data and global models at Duck. Additionally, the approach does not account for short-scale (~100 m) longshore variability, which can contribute to deviations in modelled results. This study demonstrates the potential of global datasets for storm impact mod elling, providing a first-order assessment with relevant information about storm induced erosion, which can be particularly useful in areas lacking high resolution data. However, it also highlights the need for further validation across diverse sites to enhance reliability and address methodological constraints.
- Challenges in assessing longshore transport along the gulf of cadiz coast: insights from analysis of different wave data sourcesPublication . Santos, Jacqueline; Costas, Susana; Taborda, Rui; Garzon, Juan L.; Drago, TeresaEstimating coastal sediment budgets presents significant challenges due to the complex nature of coastline configurations and the often-bimodal wave regime. This study investigates longshore sediment transport (LST) along the Gulf of Cadiz by analyzing estimates obtained from various wave data sources and employing various approaches. The sensitivity of transport calculations to different wave data sources and approaches is evaluated, and the impact of easterly waves, or “Levante,” is examined for the different approaches. The nearshore wave regime was simulated using the SWAN model, with offshore conditions from ERA5 hindcast and the Faro buoy. Results were validated using observational data and LST was estimated using a deep water approximation of the CERC formula, extracting the net transport and the two components of the sediment transport: west-east and east-west. The results emphasize the critical importance of selecting appropriate forcing for applied models to simulate the nearshore wave regime and estimate sediment transport.
- Comprehensive approaches to climate adaptation and coastal management: insights from the Brazilian coast and a Southeast Asian PortPublication . Santos, Paulo Rosa; V. C. Taveira Pinto, Francisco; Carrasco, Rita; Bento, Ana Margarida; Ferradosa, Tiago João FazeresUrban coastal areas are highly vulnerable to climate change due to their proximity to the sea and dense infrastructure, making resilience-building essential as threats such as sea-level rise, pollution, and intensified storms worsen. Environmental and climate planning are crucial for adapting these regions to potential climate-related disasters. The research presented in this issue provides practical evaluations of planning and monitoring in coastal regions, offering valuable insights for enhancing local management. Environmental planning combines data from the natural environment with socio-economic information to preserve the integrity of both natural and human-made elements. In this issue, the work of Bonilha et al. (2024) presents a geoenvironmental zoning of the municipality of Rio Grande, which establishes guidelines for sustainable land use by balancing the physical characteristics of the environment with socio-economic needs. This zoning not only provides historical, environmental, and legislative knowledge, but also evaluates the land’s usability in light of changes in landscape structure and function (Bonilha et al., 2024). An essential part of climate planning is monitoring how coastal environments change over time, which informs the development of climate-resilient strategies. In this issue, Neto et al. (2024) conducted a seasonal monitoring study of physical and chemical water variables in the estuary of the Goiana and Megaó rivers, a protected area for artisanal fisheries. The authors identified seasonal variations in temperature, salinity, and transparency between the dry and rainy seasons, revealing that the estuary is experiencing hypoxia, which threatens local biodiversity. The area’s status as a conservation unit for artisanal fishing is particularly important due to the economic reliance of local communities on biodiversity (Neto et al., 2024). Also, building on insights gained from monitoring data, the study by Coelho et al. (2024) provides a comprehensive understanding of how changes in tide nodal modulation affect tidal constituents and regimes worldwide. These results are crucial for precisely quantifying the impacts of climate change on tidal patterns (Coelho et al., 2024).
- Contrasting short-term shoreline behaviour after the construction of sinusoidal groynes in NE BrazilPublication . Vasconcelos, Yan; Paula, Davis de; Ferreira, Óscar; Leisner, MelvinCoastal structures, such as groynes and breakwaters, disrupt coastal processes and often promote sediment accumulation updrift and erosion downdrift. However, complex or different groyne designs, such as curved groynes can lead to different behaviours that are still poorly understood. This study investigated the short-term morphological changes caused by the construction of three sinusoidal groynes as a coastal restoration/defence measure at Icaraí Beach, Northeast Brazil. The methodology consisted of monthly field surveys using GNSS-RTK, UAS and high resolution CBERS-4A satellite imagery before, during and after completion of the defence structure. The results were compared with available wave data to provide a comprehensive understanding of the coastal behaviour. The curved shape of the groyne resulted in erosion and accumulation cells that were different (and in some cases opposite) to traditional structures. Beach formation and progradation was observed along a sheltered section of approximately 130 m of shoreline located downdrift, while severe erosion was recorded further downdrift, culminating in the partial loss of a property. The study highlights the challenges facing coastal protection measures and emphasises the need for sustainable solutions to mitigate future risks and prevent coastal degradation.
- Controls on blowout evolution in southern Portugal: A 49-year analysisPublication . Talavera, Lara; Costas, Susana; Ferreira, ÓscarBlowouts are wind-formed depressions that help maintain the sediment budget and enhance biodiversity in coastal dunes. However, the drivers controlling their evolution and the temporal scales associated to their genesis, development and decay phases remain unclear. To address this, the morphometric characteristics of a series of blowouts on the Ancao ˜ Peninsula (South Portugal) were digitized using imagery from 1972 to 2021, and used to analyse changes in the number of blowouts, total area, morphometric characteristics (width, length, orientation), and elongation rate over time. These data were compared with metocean time series and human activities, allowing the identification of blowout phases, drivers, and associated temporal scales. This work revealed that the blowout genesis phase primarily arised from the impact of physical external factors (e.g., nonstorm low-to-moderate winds blowing out sand from dune scarp irregularities formerly created by extreme wave events), creating incisions across the foredune crest, and lasted 1 or 2 years. The blowout development phase, still ongoing, was characterized mainly by blowout expansion and rotation of large blowouts from North northeast (NNE) to the East-northeast (ENE) controlled by external physical forces at specific times (e.g., low to-moderate winds) and blowout internal factors (e.g., size and orientation). Complete blowout decay phases were not observed, except the complete artificial sealing of some blowouts due to fencing, which lasted 4 years. These findings suggest that a complete and natural blowout genesis-development-decay cycle could likely take more than five decades, with complex and spatiotemporally variable ecogeomorphic feedbacks driving their evolution. The only phase reversal documented was the reactivation of the artificially sealed blowouts, due to storm impacts. Allowing the dune and blowouts to evolve naturally appears to be the current best approach for the dune management at the studied area.
- A critical analysis of the marina environmental risk assessment method applied to PortugalPublication . Neves, Maria C.; Cravo, Alexandra; Jacob, José; Correia, CátiaThe MERA (Marina Environmental Risk Assessment) procedure was applied for the first time along the coast of Portugal to classify the risk of 26 marinas on water quality. A risk ranking Atlas was produced to provide managers or decision-makers with spatial information that can help achieve sustainable development goals. The results indicate that the eight marinas in the south coast of the country (Algarve) face the highest risk, primarily due to pressures from navigation activities. However, the ranking generated along the Algarve using indicators of trophic status (TRIX and Eff. Coeff.) based on chemical analysis of in-situ water samples do not align with MERA. The MERA methodology, as it stands, presents significant limitations. Specifically, it does not account for water chemical parameters, sediment contamination, or temporal variability, all of which are crucial for accurate assessments. To enhance the robustness of MERA, this study suggests incorporating additional parameters and metrics that encompass broader environmental indicators.
- Decoding storm response in geologically controlled coastal barriers using XBeachPublication . Kümmerer, Vincent; Loureiro, Carlos; Ferreira, ÓscarStorm-induced morphological changes in coastal barriers are primar ily driven by hydrodynamic forcing. However, in rock-fronted coasts the pres ence of geological features can modulate storm impacts, but the extent to which these non-dynamic variables influence barrier morphological response to storms is still poorly understood. This study explores the influence of intertidal rock plat forms on storm-driven morphological changes. Using the process-based XBeach model, dune erosion during an energetic winter storm was simulated across dif ferent schematic cross-shore profiles, incorporating variable intertidal rock plat form configurations. The schematic profiles are based on existing barrier pro files in the Outer Hebrides, NW Scotland. Calibration of the model involved adjusting friction coefficients of exposed bedrock surfaces to improve the abil ity to reproduce observed nearshore wave heights and morphological changes in pre- and post-storm profiles. The results show that higher intertidal rock plat forms (above mean sea level) are associated with reduced dune erosion, while lower rock platforms are associated with more extensive dune erosion. This high lights the complex interaction between geological control and storm impacts, with implications for improved understanding of coastal resilience and storm-driven morphosedimentary dynamics in rock-fronted barrier systems.
- Digital twin modelling for a renewable energy community: a case study of the culatra island’s smart gridPublication . Ogunsola, Idris Olalekan; Santos, Joni; Monteiro, Jânio; Pacheco, AndréThis study develops and tests a Digital Twin (DT) of the Culatra Island’s distribution grid to enable the evaluation of demand side management strategies, in the scope of Renewable Energy Communities. Built in MATLAB/Simulink and structured across five functional layers, the DT integrates real-world data from five photovoltaic (PV) production units, monitored and fixed electrical loads, and realistic network parameters derived from the island’s infrastructure. Three steady-state test scenarios were simulated to assess voltage stability, and power flow under: 1) baseline grid operation without PV generation, 2) distributed PV integration under normal load conditions, and 3) high-demand operation near generationload equilibrium. Results show that PV integration improves voltage regulation and reduces losses through localized energy injection and bidirectional power flow. However, under peak load conditions, the system exhibits significant undervoltage, revealing the need for advanced control strategies and infrastructure reinforcement. Overall, the DT proves to be an effective analytical and decision-support tool for optimising distributed energy systems. This work provides a replicable application-oriented framework for data-driven planning in emerging Renewable Energy Communities and supports Culatra Island’s transition toward full energy self-sufficiency. Unlike prior studies that report generalized benefits of PV integration, this work explicitly identifies voltage instability thresholds under high-demand conditions in a real REC configuration, providing actionable insight into when passive operation becomes insufficient.
- Empowering maritime spatial planning and marine conservation efforts through digital engagement: the role of online platformsPublication . Gutierrez, Débora; Calado, Helena; Toor, Femke van; Moreira, Mariana; Paramio, Maria Luz; Martins, Francisco; Santos, Natali; Melo, Neuza; Newton, AliceThis study addresses the performance of digital platforms in enhancing ocean governance by improving communication and collaboration among stakeholders. It analyses several platforms based on their collaborative initiatives, digital tools, and ability to function as networks of knowledge. The findings show that these platforms bridge gaps between regional, national, and non-governmental organisations, promoting informed decision making. Their online presence enhances transparency and engagement, especially postCOVID-19. This study highlights the need for hybrid platforms combining informative and interactive elements to better serve both experts and the public. From this analysis, some recommendations are drawn to provide rules and design for the cooperation and co-design of a platform to foster better communication, collaboration, and sustainable ocean management practices.
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