Modelización del acoplamiento entre el Giro Subtropical del Atlántico Norte y el afloramiento costero africano

Memoria de tesis doctoral presentada por Irene Laiz Alonso para obtener el título de Doctora en Física Funfamental y Aplicada por la Universidad de Las Palmas de Gran Canaria (ULPGC), realizada bajo la dirección del Dr. Josep Lluis Plegrí Llopart del Institut de Ciències del Mar (ICM-CSIC) y el Dr. Pablo Sangrà InciarteEste trabajo de tesis se ha realizado dentro de las líneas de investigación del Grupo de Oceanografía Física del Departamento de Física de la Universidad de Las Palmas de Gran Canaria. Uno de los focos de interés de dicho grupo ha sido, tradicionalmente, el estudio de la recirculación del ramal oriental de la Corriente de Canarias y su vinculación al afloramiento costero del noroeste africano. Así, este trabajo surgió de la necesidad de demostrar físicamente la hipótesis de acoplamiento entre ambos sistemas. El análisis de la circulación en el océano costero y su influencia sobre la circulación del océano interior se ha llevado a cabo mediante el desarrollo de un modelo de circulación oceánica sencillo y la modificación de sus condiciones de contorno en el borde oriental. El uso de la teoría cuasigeostrófica para definir las ecuaciones del modelo ha supuesto la ventaja de poder traducir en términos de vorticidad los procesos físicos que dan lugar a las nuevas condiciones de contorno. [...]Peer Reviewe

Erasmus experience between the University of Cadiz (Spain) and the University of Algarve (Portugal)

A mobility program was carried out during the last two years between the Universities of Cadiz (Spain) and Algarve (Portugal) under the EU funded Erasmus+ Mobility for Teaching. The objective of the mobility was twofold: on one hand, it included the strengthening of the existing scientific cooperation between the University of Cadiz (home institution) and the University of Algarve (host institution) in the field of the Gulf of Cadiz Physical Oceanography; on the other hand, it pretended to improve the teaching quality, focusing on both the lecturers and the students. Both institutions have long ties of cooperation that have recently been intensified under the umbrella of the International Campus of Marine Excellence (CeiMar). Specific objectives oriented towards the lecturers included the exchange of teaching experiences among them as well as the comparison of teaching strategies and methodologies between the host and home institutions at the Master level in order to evaluate and enhance the best teaching practices with the aim of improving the students learning process. Specific objectives oriented towards the students included: (1) to provide local students that cannot afford studying a Master degree abroad with a foreign teacher in the discipline that will offer them different added expectations; (2) to teach students different subjects from those taught at the host institution, thus benefitting from new scientific knowledge and experiences. It must be pointed out that the subject taught by the home institution lecturer represents a competence lacking at the host institution, hence complementing the program of the discipline and providing an added value to the Master degree. Informal questionnaires carried out among students by the host institution revealed that they evaluated having a foreign teacher as a very positive experience. In terms of research, collaboration among both institutions is of great importance because they are both located within the same geographic region and hence, they share common interests. The mobility promoted finishing on-going collaborative publications as well as sharing new research experiences, data and knowledge, hence leading to an improvement of the Physical Oceanography state-of-the-art in the Gulf of Cadiz. In fact, two scientific papers on the Gulf of Cadiz circulation system and two on the storm climate along the Gulf of Cadiz and its relation with coastal hazards have been recently published as a direct result of the mobility program.info:eu-repo/semantics/publishedVersio

Development of tutorials to promote self-directed programming learning: application to postgraduate studies

Most students graduated in Marine Science or other related disciplines (e.g. Geology, Biology, Chemistry) lack the basic background knowledge in scientific programming and modelling (e.g. Matlab, Fortran, Python), necessary in numerical disciplines such as Physical or Coastal Oceanography. Hence, when they enroll for postgraduate studies in Oceanography they are not able to properly follow the lessons related to the above disciplines and generally become discouraged. Trying to meet the needs of those students during the lessons would result in not accomplishing the course’s program, given the fact that MSc programs have concentrated material and are extremely demanding for the students. For this reason, a collaborative effort has been made among various lecturers to develop tutorials in order to promote self-directed learning among the MSc students with the aim of alleviating those deficiencies. These tutorials were applied in two different courses and consisted in: i) a quick-start Matlab guide for NetCDF meteorological and oceanographic data handling and plotting, and ii) the use of a front-end platform for visualising, analysing and evaluating results from the state-of-the-art morphodynamic model XBEACH-G. The above methods helped the students to understand the potential of programming and numerical modelling, as well as, the importance of applying such approaches both in consulting and research-based carriers. Overall, this methodology resulted in a higher level of satisfaction among students because it offered an active, flexible and self reliant learning method that was adapted to each person’s learning pace and difficulties. Finally, the tutorials proved to be an inclusive teaching strategy able to address the needs of students with different backgrounds, learning styles, and abilities, hence providing a more efficient learning environment, in which all students could reach their potential at their own pace and feel equally valued at the end of the course

Microbenthic Net Metabolism Along Intertidal Gradients (Cadiz Bay, SW Spain): Spatio-Temporal Patterns and Environmental Factors

Microphytobenthos (MPB), the photosynthetic primary producing component of microbenthos, shows variable patterns in its biomass distribution along the intertidal gradient as a result of the interactions of factors such as light, tides, temperature, and grazing pressure. These patterns have been studied more extensively in northern European estuaries than southern European coastal systems. Even less information is available regarding temporal changes in MPB primary production rates in these systems. For this reason, we followed the seasonal changes in net production in light and dark respiration rates (determined by oxygen microelectrodes) and MPB biomass (estimated by sediment chlorophyll a) along the intertidal gradient of the inner Cadiz Bay during a year. Sediment cores were collected along two transects (five sampling stations per transect) with distinct sediment granulometry: one muddy [Puerto Real (PR)] and one muddy-sandy transect [San Fernando (SF)]. Our results show that MPB biomass and net production increased seawards reaching their maxima in winter. In contrast to what is observed in northern European systems, the higher solar irradiance and temperatures occurring in summer in southern Spain likely inhibit MPB production. In Cadiz Bay, spatial patterns of MPB biomass and net production depended on season and location due to the environmental heterogeneity observed. Environmental variables, analyzed by principal component analysis (PCA), were used to explain the variability of MPB metabolism by multiple regression. Selected principal component (PC) axes explained 60% of the net production in light and 41% of the dark respiration rates variability in PR, while they only accounted for 25% of the same rates in SF. The differences observed between transects and the variability in the environmental variables explaining them highlight the importance of considering the spatial heterogeneity of our system to estimate the contribution of MPB to the inner Cadiz Bay productivity. In our case, this contribution is significant accounting for up to 49% of the total benthic production of the inner Cadiz Bay intertidal sediments, confirming previous global estimates

An enhanced recruitment of blue whiting in the Porcupine bank (NE Atlantic) during 2020 in response to favourable environmental conditions

A Spanish bottom trawl research survey was conducted between 2001 and 2020 in the Porcupine Bank to retrieve recruitment data. The survey was routinely carried out in September with the objective of assessing the fisheries in the area. The 2020 data showed the largest abundance of age-0 blue whiting (Micromesistius poutassou), with almost twice as much than in the highest previous record (2004). Thus, this study focused on determining the environmental drivers that could explain that anomalously high abundance through their impact on the blue whiting eggs and larvae survival. For this purpose, satellite SST and chlorophyll were analyzed during the spawning season (March-April), along with reanalysis wind, salinity, and ocean currents data. Our results showed particularly low wind conditions during March and April 2020, which triggered the onset of a stable Taylor Column circulation above the Porcupine Bank, helping not only the accumulation of phytoplankton biomass, which promoted secondary productivity, but also larval retention. This was corroborated by a quantile regression fit applied on the blue whiting recruitment data (September), which showed significant positive (negative) correlations with the chlorophyll concentration (wind mixing index) during the spawning season

Looking for environmental drivers of blue whiting recruitment in the Porcupine Bank (NE Atlantic)

Although temporal and spatial match and mismatch of sh larvae with their potential prey organisms is considered the main factor regulating the year-class strength in marine sh populations, di erent environmental forcings also in uence the survival rate of larvae and therefore recruitment. In 2020, the highest abundance of year-class recruits (total lenght < 20 cm) of Micromesistius poutassou was observed in the record of the Spanish Bottom Trawl Survey on the Porcupine Bank (September) from 2001-2020. Various environmental parameters, namely chlorophyll concentration, surface salinity, temperature, ocean currents, and wind data were used to study their potential impact on the blue whiting eggs and larvae survival. Our results showed that in 2020, during the blue whiting-spawning season (March-April), the calm wind situation along with weaker ocean currents above the Porcupine Bank helped to accumulate phytoplankton biomass, thus promoting secondary productivity. The optimal salinity concentration, as well as surface temperature during this time, helped the buoyancy of eggs and larvae to the food-rich surface, thus improving the larval condition and enhanced the survival rate, which in turn resulted in the largest recruitment since 200

Environmental forcing on blue whiting year-class strength in the Porcupine bank (NE Atlantic)

The highest abundance of age-0 blue whiting Micromesistius poutassou in the Porcupine Bank since 2001 was observed in 2020. Various environmental parameters, namely chlorophyll concentration, surface salinity, temperature, ocean currents, and wind data were used to study their potential impact on the blue whiting eggs and larvae survival. Our results showed that in 2020, during the blue whiting-spawning season (March-April), the calm wind situation along with weaker ocean currents above the Porcupine Bank helped to accumulate phytoplankton biomass, thus promoting secondary productivity. The optimal salinity concentration, as well as surface temperature during this time, helped the buoyancy of eggs and larvae to the food-rich surface, thus improving the larval condition and enhanced the survival rate, which in turn resulted in the highest year-class recruitment since 2001

Prácticas de Mecánica de Fluidos

Prácticas de laboratorio propuestas para la asignatura de Mecánica de Fluidos en el Grado en Arquitectura Naval e Ingeniería Marítima

Assessing the trophic ecology of the invasive Atlantic Blue Crab Callinectes sapidus in the coastal waters of the Gulf of Cadiz

Callinectes sapidus, the invasive blue crab from the west of the Atlantic Ocean, has extended its distribution along the Atlantic coast around the Gulf of Cadiz and increased massively since 2016. Food web studies are useful for understanding changes in ecosystems caused by exotic species. Stable isotope analysis (δ13C and δ15N) were used to assess the potential carbon sources and its trophic relationships among different ecosystems (estuaries and saltmarshes), sexes (male and females) and seasons (summer vs. autumn). Significant differences were found in the δ13C of blue crabs from the estuaries and salt-marshes (-21.2 ±2.6 vs -14.2 ±0.9, respectively). These differences may be explained by an increase in the 13C of the blue crabs from the salt-marshes, probably due to the enrichment of this isotope in the primary producers such as the salt marsh plants [1] and its preys inhabiting this ecosystem. Meanwhile, the more depleted 13C values in the estuary crabs seem to reflect a carbon source from mollusks and fish derived from decomposing detritus. Among the ecosystems analyzed, δ15N was only significantly enriched in the crabs of the Guadalquivir estuary and was higher in males than females. Also, seasonal differences were found in this estuary in both sexes, by a decrease in the 15N values between summer and autumn. Those differences, can be explained by the fact that the Guadalquivir estuary suffers nitrogen hyper-nitrification due to intensive agriculture and is more noticeable in the upper part of the estuary, to which the males are more associated due to their life cycle. Previous studies reported, the diet of C. sapidus seems to be opportunistic, dependent on the food availability in different habitats [2], with a divergence in sexes induced by different spatial distributions. Future studies analyzing the stomach content and trophic behavior should be conducted to clarify our results

Desarrollo de tutoriales para promover el auto-aprendizaje entre estudiantes de postgrado

Gran parte de los graduados en Ciencias del Mar o disciplinas similares carecen de una formación básica en programación científica y modelización numérica. Como consecuencia, cuando acceden a ciertos estudios de postgrado, encuentran grandes dificultades para seguir los contenidos de muchas asignaturas. Otra consecuencia directa de esta falta de formación es que, el profesor se ve obligado a reducir el programa de la asignatura. Varios profesores han llevado a cabo un esfuerzo cooperativo para promover el auto-aprendizaje de los alumnos. Se desarrollaron tutoriales centrados en dos asignaturas del Máster de Oceanografía que consistieron en: (i) una guía para la lectura, tratamiento y representación gráfica de datos oceanográficos y meteorológicos con Matlab y (ii) una aplicación interactiva para visualizar, evaluar y analizarlos resultados del modelo morfodinámico XBEACH-G. En general, esta metodología incrementó el nivel de satisfacción de los estudiantes con las asignaturas implicadas, ya que les proporcionó un método de aprendizaje activo, flexible y autónomo. Además, este aumento en la motivación les permitió entender el gran potencial de la programación científica y los modelos numéricos y su relevancia tanto para la investigación académica como para el sector empresarial. El uso de los tutoriales demostró ser una estrategia de educación inclusiva capaz de atender las necesidades de estudiantes con diferentes grados de formación, aptitud y capacidad de aprendizaje, generando por lo tanto un ambiente de aprendizaje más eficiente en el que todos los estudiantes, protagonistas del proceso de enseñanza-aprendizaje, pudieron desarrollar su máximo potencial de manera progresiva a su propio ritmo. Por último, el trabajo cooperativo entre el profesorado, que se ha convertido a día de hoy en una nota distintiva del sistema educativo actual, permitió el intercambio de ideas y materiales. En un futuro, se espera continuar con esta filosofía y desarrollar nuevas estrategias bajo el enfoque constructivista