27 documents found, page 1 of 3
High-resolution observations of the ocean upper layer south of Cape St. Vincent...
Rautenbach, Sarah A.; Mendes da Silva de Sousa, Carlos A; Carapuço, Mafalda; Relvas, PauloThis article presents an Eulerian physical and biogeochemical dataset from the Iberian Margin Cape St. Vincent Ocean observatory (IbMa-CSV), a facility of the European Multidisciplinary Seafloor and water column Observatory European Research Infrastructure Consortium (EMSO-ERIC), located 10 nautical miles south of Cape St. Vincent (Portugal), the southwest tip of the Iberian Peninsula and western limit of the n...
Upwelling processes variability and water circulation along the northern margin...
de Oliveira Júnior, Luciano; Relvas, Paulo; Garel, ErwanThe present study investigates the contributions of upwelling mechanisms (coastal upwelling from boundary divergence and Ekman pumping from spatially variable wind) at the northern margin of the Gulf of Cadiz (NMGoC) based on high-resolution wind. The effects of the spatiotemporal upwelling mechanisms variability are then explored using current observations along with sea surface temperature and sea level anoma...
High-resolution observations of the ocean upper layer south of Cape St. Vincent...
Rautenbach, Sarah A.; Mendes da Silva de Sousa, Carlos A; Carapuço, Mafalda; Relvas, PauloThis article presents an Eulerian physical and biogeochemical dataset from the Iberian Margin Cape St. Vincent Ocean observatory (IbMa-CSV), a facility of the European Multidisciplinary Seafloor and water column Observatory European Research Infrastructure Consortium (EMSO-ERIC), located 10 nautical miles south of Cape St. Vincent (Portugal), the southwest tip of the Iberian Peninsula and western limit of the n...
Monitoring invasive macroalgae in southern Portugal: drivers and citizen scienc...
Jiménez, Javier; Simes, Dina; Abecasis, Ana Rita Costa; Relvas, Paulo; Garel, Erwan; Martins, Paula Ventura; Santos, RuiUnder certain environmental and oceanographic conditions, macroalgae can overgrow and accumulate in massive quantities on beaches, causing serious ecological and economic impacts. To address this problem, a citizen science monitoring platform was created to determine the spatial and temporal distribution of macroalgae accumulations along the beaches of Algarve in southern Portugal, with the aim to assess the ex...
Piece‐wise constant cluster modelling of dynamics of upwelling patterns
Nascimento, Susana; Martins, Alexandre; Relvas, Paulo; Luis, Joaquim; Mirkin, BorisA comprehensive approach is presented to analyse season's coastal upwelling represented by weekly sea surface temperature (SST) image grids. Our three-stage data recovery clustering method assumes that the season's upwelling can be divided into shorter periods of stability, ranges, each to be represented by a constant core and variable shell parts. Corresponding clustering algorithms parameters are automaticall...
The signature of NAO and EA climate patterns on the vertical structure of the c...
Georg, Tina; Neves, Maria; Relvas, PauloThe current study aims to analyse the vertical structure of the ocean during upwelling events using in situ and modelled data. Additionally, the influence of climate patterns, namely the North Atlantic Oscillation (NAO) and the East Atlantic (EA) pattern, on the vertical structure and their impact on the upwelling activity are assessed for a period of 25 years (1993-2017). The study focuses on the central part ...
Novel cluster modeling for the spatiotemporal analysis of coastal upwelling
Nascimento, Susana; Martins, Alexandre; Relvas, Paulo; Luis, Joaquim; Mirkin, BorisThis work proposes a spatiotemporal clustering approach for the analysis of coastal upwelling from Sea Surface Temperature (SST) grid maps derived from satellite images. The algorithm, Core-Shell clustering, models the upwelling as an evolving cluster whose core points are constant during a certain time window while the shell points move through an in-and-out binary sequence. The least squares minimization of c...
Kinematics of surface currents at the northern margin of the Gulf of Cádiz
De Oliveira Júnior, Luciano; Relvas, Paulo; Garel, ErwanThe subtidal surface water circulation at the northern margin of the Gulf of Cadiz, at the southern extremity of the Iberian upwelling system, is described based on validated hourly high-frequency radar measurements from 2016 to 2020. Statistical analyses (mean, standard deviation, eccentricity and empirical orthogonal functions) are applied to the dataset, which is completed with ADCP time series from multiple...
Variability patterns and phenology of harmful phytoplankton blooms off southern...
Lima, M.J.; Relvas, Paulo; Barbosa, AnaHarmful algal blooms (HABs) negatively impact coastal ecosystems, fisheries, and human health, and their prediction has become imperative for effective coastal management. This study aimed to evaluate spatialtemporal variability patterns and phenology for key toxigenic phytoplankton species off southern Portugal, during a 6-year period, and identify region-specific environmental drivers and predictors. Total ab...
The structure of incipient coastal counter currents in South Portugal as indica...
De Oliveira Júnior, Luciano; Garel, Erwan; Relvas, PauloThe alongshore subtidal water circulation along the South Portugal inner shelf is characterized by the temporal alternation of equatorward (i.e., broadly eastward) flows related to coastal upwelling processes and poleward (i.e., broadly westward) Coastal Counter Currents (CCCs). The objective of this study is to get insights about the main drivers of CCCs based on kinematic parameters describing the structure o...