lunes, agosto 10, 2020

DEFENSA DE TFG: LAURA VÁZQUEZ ÁLVAREZ

Laura Vázquez Álvarez, alumna de Grado en Ciencias del Mar en la Universidad de Las Palmas de Gran Canaria, ha realizado la presentación y defensa de su Trabajo Final de Grado (TFG). El TFM, dirigido por la Dra J. Magdalena Santana-Casiano y el Dr. Melchor González-Dávila, se titula "Carbonate Chemistry variability in the East Coast of Gran Canaria island". 

Este trabajo se ha centrado en el análisis de datos oceanográficos obtenidos en la boya oceanográfica Morgan I, localizada en la Bahía de Gando desde el 26 de Marzo de 2020. Para el TFG se han analizado los dos primeros meses.

Estos datos se enmarcan dentro del proyecto CanOA, dentro del programa público-privado CanBIO del Gobierno de Canarias y la Fundación Loro Parque.

A continuación se puede leer un resumen del trabajo, en inglés.

Here it is shown the first-two-month data obtained from the oceanographic buoy MORGAN I, set in Gando Bay the 26th of March 2020. Physico-chemical and biological parameters were studied in order to know the variation of the carbonate system and possible acidification. It was seen the expected changes due to the arrival of the springtime: decreases in oxygen concentration and pH, and rises in temperature, salinity and seawater carbon dioxide fugacity, this last one mainly controlled by temperature oscillations. It was also seen a relationship between SST, SSS and moon phases caused by the variation of the tidal strength. A budget of CO2 flux was also made, concluding that Gando Bay acts as a sink of CO2 atm, with a rate of 15.5 tons per day for March-May. Anyway, this research is time-limited, so it has to be continued in order to know the whole year seasonal variation.




lunes, agosto 03, 2020

DEFENSA DE TFM: DAVID CURBELO HERNÁNDEZ

La pasada semana, el alumno del Máster Interuniversitario en Oceanografía, David Curbelo Hernández presentó y defendió el Trabajo Final de Máster (TFM) titulado "Temporary evolution of the carbon dioxide system parameters in time series" cuyos tutores fueron Melchor González-Dávila y J. Magdalena Santana-Casiano.

En resumen, este trabajo estudió la variabilidad estacional y espacial de fugacidad y flujos de CO2 en el Noreste Atlántico, entre las Islas Canarias y el Estrecho de Gibraltar, en una región de transición entre el afloramiento de la costa Noroeste Africana y las aguas oligotróficas del giro subtropical del Atlántico Norte. El monitoreo y recolección de datos fue llevado a cabo entre febrero de 2019 y febrero de 2020 por el barco de observación voluntaria (VOS) RENATE P.

Este trabajo es parte del proyecto CanOA, enmarcado en el programa de investigación CanBIO, co-financiado por la Fundación Loro Parque y el Gobierno de Canarias. 

Este trabajo de máster tamibén fue presentado previamente en el ISMS 2020, como comunicación oral en el evento SIQUIMAR.

El resumen del trabajo, en inglés, se pesenta a continuación:

Oceans are important CO2 sinks that buffer the increase in their atmospheric concentration derived from anthropogenic emissions, which has produced alterations, not only in the Earth's climate, but also in marine biogeochemistry. One of the largest and most important ocean sinks, and therefore one of the most susceptible to disturbances, is the North Atlantic, so the study of the CO2 system in this basin is essential to understand and know to confront the Global Change.

This work has focused on the study of the seasonal variability of the CO2 system and the air-sea CO2 exchange based on data collected by a voluntary observatory ship (VOS) in the Northeast Atlantic, in a region of interest between the Northwest African coastal upwelling and the oligotrophic waters of the North Atlantic subtropical gyre between the Canary Islands and the Strait of Gibraltar (~28-36ºN). The results show the seasonal and spatial variability of the air-sea CO2 fluxes in this region, mainly driven by variations in CO2 solubility in seawater controlled by temperature. The system behaves as a source in summer with maximum average CO2 fluxes around 2 mmol m-2d-1 in oceanic waters of the Canary archipelago (2.147 ± 0.262 and 1.992 ± 0.358 mmol m-2d-1 on the routes between Gran Canaria and Tenerife and between Tenerife and Lanzarote respectively); and as a strong sink in the cold months, with minimum average CO2 fluxes around -3 mmol m-2d-1 during winter throughout the study region. Moreover, the averages of fCO2 are in the range between ~420 µatm in summer and ~370 µatm in winter in all routes, observing some longitudinal variability in inter-island routes and in the Strait of Gibraltar associated with hydrographic differences; and an evident latitudinal variability along the African coast related to regional differences in the intensity of the coastal upwelling that explain the minimum values ​​of fCO2 and FCO2 determined in the region closest to Cape Ghir and in the Strait of Gibraltar, where the system has behaved as a CO2 sink in all seasons of the year. Finally, it was determined in this work an average CO2 flux of -4.78 ± 0.6 Tg year-1, which indicates that this area of ​​the Northeast Atlantic behaves as a net CO2 sink.