https://accedacris.ulpgc.es/jspui/handle/10553/58251 Elementos cuyos archivos sólo son accesibles desde la ULPGC Fri, 03 Apr 2026 10:16:50 GMT 2026-04-03T10:16:50Z https://accedacris.ulpgc.es/jspui/handle/10553/143625 Título: Tidal and diurnal wind-driven current variability around Gran Canaria Autores/as: Piñol Espla, Paula Resumen: Gran Canaria is an island with a steep and narrow platform in the eastern Atlantic Ocean. Current meter records from 1986 to 1998 were analysed using both harmonic least squares and response methods. Our results confirm that semidiurnal currents are primarily governed by the astronomical tide and exhibit strong spatial variability. The largest tidal currents were observed on the southeastern and western shelf regions, where the velocities oscillate in-phase with the sea level with amplitudes exceeding 40 cm s⁻¹, while the northern and southwestern sectors showed significantly weaker tidal flows oscillating near 90º out-of-phase with respect the sea level. Diurnal wind forcing, particularly from sea breezes, also contributes to current variability, but its influence is spatially heterogeneous. Breeze-induced driven variability appears significant only in sectors where the insular shelf is broad. However, a substantial portion of the variance in the diurnal band is not coherent with either tidal or wind forcing. This suggests the presence of near-inertial oscillations originating in the open ocean. Furthermore, the response method proved to be an effective tool for analysing tidal currents, allowing for the use of short-duration records. It offers a robust alternative to traditional harmonic methods and expands the possibilities for characterizing tides in regions with limited data. The findings also underscore the potential of tidal currents as a source of renewable marine energy, owing to their high predictability and stability, which makes them particularly suitable for small, isolated systems such as oceanic islands. Wed, 01 Jan 2025 00:00:00 GMT https://accedacris.ulpgc.es/jspui/handle/10553/143625 2025-01-01T00:00:00Z https://accedacris.ulpgc.es/jspui/handle/10553/143621 Título: Linking salinity and precipitation through moisture transport: a study for the North Atlantic Autores/as: Rosquete Estévez, Aleida Resumen: Sea surface salinity (SSS) is a key indicator of the ocean–atmosphere freshwater balance and plays a central role in global moisture transport. This study investigates how extreme SSS anomalies in the subtropical North Atlantic (NATL) source region influence atmospheric moisture pathways and precipitation in surrounding continental and island sink regions. Monthly SSS data (1985–2014) from the EN4.2.2 dataset were combined with high-resolution Lagrangian moisture tracking via FLEXPART-WRF simulations. Extreme salinity events (±1σ, ≥2 consecutive months) were identified and linked to composite anomalies of evaporation, vertically integrated vapor transport (IVT), mean sea-level pressure, geopotential height, and vertical velocity. Our results show that high-salinity episodes, driven by prolonged evaporation and anticyclonic regimes, enhance westward moisture export to the Caribbean and Central America. Conversely, low-salinity events coincide with cyclonic anomalies that redirect moisture toward southwestern Europe, notably the Iberian Peninsula and Madeira. Precipitation responses in island regions were more heterogeneous, reflecting their proximity to the source. A significant lagged correlation with the ONI index suggests ENSO’s influence on NATL salinity variability. These findings demonstrate that SSS anomalies can serve as diagnostic signals—and potential predictors—of regional hydrological changes, offering new insights for medium-range precipitation forecasting. Wed, 01 Jan 2025 00:00:00 GMT https://accedacris.ulpgc.es/jspui/handle/10553/143621 2025-01-01T00:00:00Z https://accedacris.ulpgc.es/jspui/handle/10553/141541 Título: Environmental controls on the phytoplankton community structure in the Equatorial Atlantic Ocean Autores/as: Socorro Alonso, Adriana Del Pino Resumen: This study analyzes how environmental conditions structure the distribution of phytoplankton in the Equatorial Atlantic, a region marked by strong seasonality in primary production, influenced by wind variability and the position of the Intertropical Convergence Zone (ITCZ). Based on data collected during the M181 expedition in 2022, two distinct phytoplankton habitats were identified along a zonal transect through statistical analyses and oceanographic variables. Habitat 1, located in the eastern sector, was characterized by a high abundance of diatoms of the genus Hemiaulus, presumably associated with nitrogen-fixing symbionts, in waters with lower salinity, shallower nutriclines, and stronger stratification. These conditions suggest a favorable environment for diatom diazotroph associations in the absence of nitrate. In contrast, Habitat 2, in the western sector, exhibited oligotrophic, with dominance of the cyanobacterium Trichodesmium, favored by phosphate availability and possibly enhanced iron input via wet deposition. Other groups such as Synechococcus and Prochlorococcus were also present, especially Synechococcus, which dominated in several stations. The comparison of techniques such as flow cytometry, optical imaging (PlanktoScope), and pigment analysis (CHEMTAX) helped validate these community patterns. Although the RDA statistical model explained only 21 % of the variation in community structure, potential ecological relationships were identified, such as an association between Synechococcus and silicate, which may reflect a physiological function not yet fully understood. Overall, the results highlight the importance of spatial variability in the analysis of marine biological processes and emphasize the value of integrated methodological approaches to understand the interaction between phytoplankton functional groups and their physicochemical environment in understudied oceanic regions Wed, 01 Jan 2025 00:00:00 GMT https://accedacris.ulpgc.es/jspui/handle/10553/141541 2025-01-01T00:00:00Z https://accedacris.ulpgc.es/jspui/handle/10553/141544 Título: Construyendo co-gobernanza en el sector pesquero de las Islas Canarias, España Autores/as: López Valenzuela, German Carlos Arturo Resumen: Establecer espacios de co-gobernanza en el sector pesquero de las Islas Canarias, un territorio geográficamente aislado y vulnerable a externalidades, es una oportunidad de contribuir a la solución de retos como la degradación ambiental y pérdida de biodiversidad; la seguridad y soberanía alimentaria; y el desarrollo socioeconómico. Los resultados del análisis comparativo de los estudios realizados en Gran Canaria y Tenerife indican que la concordancia entre expertos a la hora de reconocer las dificultades de la pesquería artesanal es mayor que entre los participantes de diferentes perfiles sociológicos. Asimismo, y de mayor importancia, se identificó que los participantes coincidieron en los problemas más desafiantes a pesar de no tener acceso a los problemas señalados por la literatura científica. El estudio concluye que existe la posibilidad de implementar un marco de trabajo de co- gobernanza en la gestión de las pesquerías artesanales de las islas del archipiélago, en tanto se den las condiciones facilitadoras y los acuerdos institucionales apropiados.; Establishing co-governance spaces in the fishing sector of the Canary Islands, a geographically isolated territory vulnerable to externalities, is an opportunity to contribute to the solution of challenges such as environmental degradation and biodiversity loss; food security and sovereignty; and socioeconomic development. The results of the comparative analysis of the studies conducted in Gran Canaria and Tenerife indicate that there is greater agreement among experts in recognizing the difficulties of artisanal fisheries than among stakeholders with different sociological profiles. Furthermore, and more importantly, it was found that stakeholders agreed on the most challenging problems despite not having access to the issues highlighted in the scientific literature. The study concludes that there is a possibility of implementing a co-governance framework in the management of artisanal fisheries on the small-scale fisheries of the archipelago, provided the enabling conditions and appropriate institutional arrangements are in place Wed, 01 Jan 2025 00:00:00 GMT https://accedacris.ulpgc.es/jspui/handle/10553/141544 2025-01-01T00:00:00Z