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- Effects of sea level rise on salinity and tidal flooding patterns in the Guadiana EstuaryPublication . Mills, Lara; Janeiro, João; Martins, FlávioSea level rise is a worldwide concern as a high percentage of the population accommodates coastal areas. The focus of this study is the impact of sea level rise in the Guadiana Estuary, an estuary in the Iberian Peninsula formed at the interface of the Guadiana River and the Gulf of Cadiz. Estuaries will be impacted by sea level rise as these transitional environments host highly diverse and complex marine ecosystems. The major consequences of sea level rise are the intrusion of salt from the sea into fresh water and an increase in flooding area. As the physical, chemical, and biological components of estuaries are sensitive to changes in salinity, the purpose of this study is to further evaluate salt intrusion in the Guadiana Estuary caused by sea level rise. Hydrodynamics of the Guadiana Estuary were simulated in a two-dimensional numerical model with the MOHID water modeling system. A previously developed hydrodynamic model was implemented to further examine changes in salinity distribution in the estuary in response to sea level rise. Varying tidal amplitudes, freshwater discharge from the Guadiana River and bathymetries of the estuary were incorporated in the model to fully evaluate the impacts of sea level rise on salinity distribution and flooding areas of the estuary. Results show an overall increase in salinity and land inundation in the estuary in response to sea level rise.
- Improving the response to operational pollution in the South Iberian coast A Super-Ensemble backtracking approachPublication . Janeiro, João; Sepp Neves, Antonio Augusto; Martins, Flávio; Campuzano, FranciscoAlthough for the general public marine oil pollution happens when an oil tanker sinks in the ocean or an accident occurs in an oil platform, most of the oil entering the world ocean does it along less obvious paths. This research work focus on operational spills. It provides a first indication of the uncertainty associated to backtracking simulations using solutions from several operational models available on the internet for the South Iberia region. The suitability of using a Super-Ensemble approach as a way of minimizing the uncertainty was also investigated. The methodology was validated using drifting buoys available for the region. Results show the advantages of using the Super-Ensemble while pointing out for the importance of the atmospheric forcing in this region due to its characteristic mesoscale activity. The absence of more trajectories sparse in time and geographic coverage was a limitation found.
- The impact of Sea level rise in the guadiana estuaryPublication . Mills, Lara; Janeiro, João; Sepp Neves, Antonio Augusto; Martins, FlávioUnderstanding the impact of sea level rise on coastal areas is crucial as a large percentage of the population live on the coast. This study uses computational tools to examine how two major consequences of sea level rise: salt intrusion and an increase in water volume affect the hydrodynamics and flooding areas of a major estuary in the Iberian Peninsula. A 2D numerical model created with the software MOHID was used to simulate the Guadiana Estuary in different scenarios of sea level rise combined with different freshwater flow rates considering varying tidal amplitudes. An increase in salinity was found in response to an increase in mean sea level in both high and low freshwater flow rates at all areas around the estuary. An increase in flooding areas around the estuary was also positively correlated with an increase in mean sea level. (C) 2020 The Authors. Published by Elsevier B.V.
- MEC: A Mesoscale events classifier for oceanographic imageryPublication . Pieri, Gabriele; Janeiro, João; Martins, Flávio; Papini, Oscar; Reggiannini, MarcoThe observation of the sea through remote sensing technologies plays a fundamentalan role in understanding the state of health of marine fauna species and their behaviour. Mesoscale phenomena, such as upwelling, countercurrents, and filaments, are essential processes to be analysed because their occurrence involves, among other things, variations in the density of nutrients, which, in turn, influence the biological parameters of the habitat. Indeed, there is a connection between the biogeochemical and physical processes that occur within a biological system and the variations observed in its faunal populations. This paper concerns the proposal of an automatic classification system, namely the Mesoscale Events Classifier, dedicated to the recognition of marine mesoscale events. The proposed system is devoted to the study of these phenomena through the analysis of sea surface temperature images captured by satellite missions, such as EUMETSAT’s Metop and NASA’s Earth Observing System programmes. The classification of these images is obtained through (i) a preprocessing stage with the goal to provide a simultaneous representation of the spatial and temporal properties of the data and enhance the salient features of the sought phenomena, (ii) the extraction of temporal and spatial characteristics from the data and, finally, (iii) the application of a set of rules to discriminate between different observed scenarios. The results presented in this work were obtained by applying the proposed approach to images acquired in the southwestern region of the Iberian peninsula.
- SMS-Coastal, a new Python tool to manage MOHID-based coastal operational modelsPublication . Mendonça, Fernando; Martins, Flávio; Janeiro, JoãoThis paper presents the Simulation Management System for Operational Coastal Hydrodynamic Models, or SMS-Coastal, and its novel methodology designed to automate forecast simulations of coastal models. Its working principle features a generic framework that can be easily configured for other applications, and it was implemented with the Python programming language. The system consists of three main components: the Forcing Processor, Simulation Manager, and Data Converter, which perform operations such as the management of forecast runs and the download and conversion of external forcing data. The SMS-Coastal was tested on two model realisations using the MOHID System: SOMA, a model of the Algarve coast in Portugal, and BASIC, a model of the Cartagena Bay in Colombia. The tool proved to be generic enough to handle the different aspects of the models, being able to manage both forecast cycles.
- Baseline climatology of the Canary Current Upwelling System and evolution of sea surface temperaturePublication . Mills, Lara; Janeiro, João; Martins, F.Global climate change has induced a rise in sea surface temperature (SST), although this increase is not uniform across the world. Significant variations exist between coastal and offshore waters, particularly in regions affected by upwelling processes. This study focuses on the Canary Current Upwelling System (CCUS), stretching from Northwest Iberia to Northwest Africa. High-resolution remotely sensed SST data (0.05°) from the ODYSSEA Level 4 Sea Surface Temperature Reprocessed dataset were validated with in situ measurements and employed to establish a regional climatological baseline for 1982–2012. Subsequent years were compared to this baseline to construct SST anomaly maps, revealing SST changes since 2012. The study area was further divided into sub-regions for comparative analysis. Results indicate that SST consistently increased at a higher rate offshore compared to the adjacent nearshore regions. A reference dataset spanning 1951–1981 was used to gauge SST variability between the two baselines. SST exhibited a 0.59 °C increase from 1951–1981 to 1982–2012, with a slowing of SST trends beyond the 1982–2012 baseline. This research offers valuable insights into the climatological dynamics of the CCUS. These findings enhance our understanding of this critical coastal system’s climatology, laying the groundwork for future investigations into evolving climate patterns in coastal regions.
- Development of an operational tool for oil spill forecast: application to oil exposed regionsPublication . Janeiro, João Miguel Leitão; Martins, Flávio; Relvas, PauloThe objective of the following thesis is to present a modelling methodology, based on the MOHID system, which allows the development of coastal operational models by taking advantage of already implemented regional operational models using a downscaling approach. This increase in resolution allows studying the influence of coastal scale processes in the dynamics of oil spills, while contributing to more accurate forecasts. The methodology was used to forecast the evolution of oil spills in two distinct areas both prone to oil pollution events: Southwest Portuguese Coast and the Tuscany Archipelago (Italy). In both regions an operational model was developed and validated to a good level, using several types of oceanographic data available in European and global databases. The method was tested during the Costa Concordia accident, where operational forecasts aided the Italian authorities during the fuel removal operations. Also considered in this work are the interaction between waves/currents/wind in the dynamics of oil spills at sea, the identification of mesoscale circulation patterns and their influence on the risk to accidents as well as the integration of these numeric methods with early detection and monitoring systems.
- Pathways and hot spots of floating and submerged microplastics in Atlantic Iberian marine waters: a modelling approachPublication . Rosas, Eloah; Martins, Flávio; Tosic, Marko; Janeiro, João; Mendonça, Fernando; Mills, LaraPlastic pollution has been observed in many marine environments surrounding the Iberian Peninsula, from the surface water to deeper waters, yet studies on their pathways and accumulation areas are still limited. In this study, a global ocean reanalysis model was combined with a particle-tracking Lagrangian model to provide insights into the pathways and accumulation patterns of microplastics originating in southern Portuguese coastal waters (SW Iberian). The study investigates microplastics floating on the surface as well as submerged at different water depths. Model results suggest that the North Atlantic Gyre is the main pathway for microplastics in surface and subsurface waters, transporting the microplastics southwards and eastwards towards the Mediterranean Sea and the Canary Islands. Currents flowing out of the Mediterranean Sea act as the main pathway for microplastics in deep waters, transporting the microplastics along western Iberia. An average residence time of twenty days in the coastal waters suggests that microplastics do not accumulate close to their sources due to their relatively fast transport to adjacent ocean areas. Notably, a significant proportion of microplastics leave the model domain at all depths, implying that SW Iberia may act as a source of microplastics for the adjacent areas, including the Mediterranean Sea, Morocco, the Canary Islands, Western Iberia, and the Bay of Biscay.
- Marine litter on the coast of the Algarve: Main sources and distribution using a modeling approachPublication . Rosas, Eloah; Martins, Flávio; Janeiro, JoãoThe accumulation of floating marine litter poses a serious threat to the global environment and the economy all over the world, particularly of coastal municipalities that rely on tourism and recreational activities. Data of marine litter is thus crucial, but is usually limited, and can be complemented with modelling results. In this study, the operational modelling system of Algarve (SOMA) was combined with a Lagrangian particle-tracking model and blended with scarce litter monitoring data, to provide first insights into the distribution and accumulation of floating marine litter on the Algarve coast. Different meteo-oceanographic conditions, sources regions and wind drift behaviors were considered. Field data and model results show a considerable concentration of marine litter along the beaches and coastal regions. The model also suggests that oceanographic conditions and wind drift have a great influence on the transport and accumulation rate of the floating marine litter on the coast, with the highest rates of accumulation during the winter and the counter current period, concentrated mostly on the south-western coast of the Algarve.
- Integrating technologies for oil spill response in the SW Iberian coastPublication . Janeiro, João; Sepp Neves, Antonio Augusto; Martins, Flávio; Relvas, PauloAn operational oil spill modelling system developed for the SW Iberia Coast is used to investigate the relative importance of the different components and technologies integrating an oil spill monitoring and response structure. A backtrack of a CleanSeaNet oil detection in the region is used to demonstrate the concept. Taking advantage of regional operational products available, the system provides the necessary resolution to go from regional to coastal scales using a downscalling approach, while a multi-grid methodology allows the based oil spill model to span across model domains taking full advantage of the increasing resolution between the model grids. An extensive validation procedure using a multiplicity of sensors, with good spatial and temporal coverage, strengthens the operational system ability to accurately solve coastal scale processes. The model is validated using available trajectories from satellite-tracked drifters. Finally, a methodology is proposed to identifying potential origins for the CleanSeaNet oil detection, by combining model backtrack results with ship trajectories supplied by AIS was developed, including the error estimations found in the backtrack validation. (C) 2017 Elsevier B.V. All rights reserved.