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Trabajo presentado en la EGO conference on autonomous ocean gliders and their applications, celebrada en Southampton (Reino Unido), del 26 al 29 de septiembre de 2016

Algerian eddies are the strongest and largest propagating mesoscale structures in the Western Mediterranean Sea. They have a large influence on the mean circulation, water masses and biological processes. Over 20 years of satellite altimeter data have been analyzed to characterize the propagation of these eddies using automatic detection methods and cross-correlation analysis. We found that, on average, Algerian eddy trajectories form two subbasin scale anticlockwise gyres that coincide with the two Algerian gyres which were described in the literature as the barotropic circulation in the area. This result suggests that altimetry sea surface observations can provide information on subsurface currents and their variability through the study of the propagation of deep mesoscale eddies in semienclosed seas. The analysis of eddy sea level anomalies along the mean pathways reveals three preferred areas of formation. Eddies are usually formed at a specific time of the year in these areas, with a strong interannual variability over the last 20 years., This work was supported by LaCaixa fundation through the MedClic project. The SLA data were generated by DUACS and distributed by AVISO (ftp://ftp.aviso.oceanobs.com).

Trabajo presentado en la Ocean Sciences Meeting, celebrada en Nueva Orleans, Estados Unidos, del 21 al 26 de febrero de 2016

Trabajo presentado en el 4th GODAE OceanView, celebrado en Lisboa, Portugal, del 31 de agosto al 4 de septiembre de septiembre de 2015

Trabajo presentado en el 4th GODAE OceanView, celebrado en Lisboa, Portugal, del 31 de agosto al 4 de septiembre de septiembre de 2015

Trabajo presentado en el International Liège Colloquium on Ocean Dynamics, celebrado en Liege, Bélgica, del 23 al 27 de mayo de 2015

Mesoscale eddies are relatively small structures that dominate the ocean variability and have large impact on large scale circulation, heat fluxes and biological processes.In the western Mediterranean Sea, a high number of eddies has been observed and studied in the past with in-situ observations. Yet, a systematic characterization of these eddies is still lacking due to the small scales involved in these processes in this region where the Rossby deformation radius that characterizes the horizontal scales of the eddies is small (10-15 km). The objective of this thesis is to perform a characterization of mesoscale eddies in the western Mediterranean. For this purpose, we propose to develop tools to study the fine scales of the basin. First, we develop an eddy resolving simulation of the region for the last 20 years. This simulation shows that existing altimetry maps underestimate the mesoscale signal. Therefore, we attempt to improve existing satellite altimetry products to better resolve mesoscale eddies. We show that this improvement is possible but at the cost of the homogeneity of the fields; the resolution can only be improved at times and locations where altimetric observations are densely distributed. In a second part, we apply three different eddy detection and tracking methods to extract eddy characteristics from the outputs of the high-resolution simulation, a coarser simulation and altimetry maps. The results allow the determination of some characteristics of the detected eddies. The size of the eddies can greatly vary but is around 25-30 km. About 30 eddies are detected per day in the region with a very heterogeneous spatial distribution. Unlike other areas of the open ocean, they are mainly advected by currents of the region. Eddies can be separated according to their lifespan. Long-lived eddies are larger in amplitude and scale and have a seasonal cycle with a peak in late summer, while short-lived eddies are smaller and more present in winter. The penetration depth of detected eddies has also a large variance but the mean depth is around 300 meters. Anticyclones extend deeper in the water column and have a more conic shape than cyclones.

Trabajo presentado en el 4th GODAE OceanView, celebrado en Lisboa, Portugal, del 31 de agosto al 4 de septiembre de septiembre de 2015

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena, Austria, del 12 al 17 de abril de 2015

Trabajo presentado en el Workshop Global and Regional Sea Level Variability and Change, celebrado en Palma de Mallorca (España), del 10 al 12 de junio de 2015

Trabajo presentado en el International Liège Colloquium on Ocean Dynamics, celebrado en Liege, Bélgica, del 23 al 27 de mayo de 2015

Trabajo presentado en el 8th Coastal Altimetry Workshop, celebrado los días 23 y 24 de octubre de 2014 en Lake Constance (Alemania), This study has been carried out as part of the MyOcean2 project (EU N° FP7-SPA. 2011.1.5-01-Grant Agreement 283367) project

Trabajo presentado en el 20 years of progress in Radar Altimetry, celebrado en Venecia, Italia, del 24 al 29 de septiembre de 2012

Trabajo presentado en ForoTec2011, III Foro Tecnológico de las Islas Baleares, celebrado el 24 y 25 de noviembre de 2011 en Palma de Mallorca (España), y organizado por la Dirección General de Universidades, Investigación y Transferencia del Conocimiento del Govern de las Illes Balears, la Universitat de les Illes Balears y el Instituto de Innovación Empresarial de les Illes Balears

Oceanic mesoscale and submesoscale play a key role in modulating large-scale circulation, heat fluxes transfer and primary production enhancement. Nevertheless, the high spatial and temporal variability associated with mesoscale motions makes them difficult to study with sparse in-situ observations. Alternative options rely on developing methodologies based on the combination of multi-sensor platforms in conjunction with numerical simulations., In this context, we present here the results of a 2D surface currents mapping, merging altimetry and SST data in the Balearic Sea (NW Mediterranean Sea). In a first step, the large (_100 km) scale signals are removed by subtracting the gridded Sea Level Anomaly maps (AVISO) to improve along track data. In a second step, the residuals are submitted to an objective analysis scheme with correlation scales adjusted to smaller (sub)mesoscale dynamics. A method including bathymetric constraint has been tested to provide a pseudo-dynamical boundary condition and to increase reliability in the coastal region. SST data information from satellite sensors are also integrated in the covariance function to gain resolution. A numerical model (ROMS) implemented in our study area has been used to test the sensibility of the developed methods. The results of these methods were then compared to independent data such as drifters launched in the area, several campaigns with in-situ data and glider information, revealing an improvement in the resolution of actual small scales features., Our approach allows us to characterize the main mesoscale features present in the Western Mediterranean Sea. Moreover, the combination with the numerical model permits to better understand the physical processes related to small-scale features.

Póster presentado al 5º Coastal Altimetry Workshop, celebrado en San Diego, USA, en octubre de 2011.

New monitoring technologies are being progressively implemented in coastal ocean observatories. As an example, gliders allow high resolution sampling, showing the existence of new features, such as submesoscale eddies with intense vertical motions that significantly affect upper ocean biogeochemical exchanges, an issue of worldwide relevance in a climate change context. SOCIB, is one of such systems, a new facility of facilities (covering from the coast to the open sea, and including among others a nearshore beach monitoring facility, HF radar, gliders and AUV’s, moorings, satellite, drifters and ARGO profilers, modelling), a scientific and technological infrastructure which is providing free, open, quality controlled and timely streams of oceanographic and coastal data and also modelling services. SOCIB takes profit of the strategic position of the Balearic Island at the Atlantic/Mediterranean transition area, one of the ‘hot spots’ of biodiversity in the world’s oceans. As an example of on-going SOCIB operations, since January 2011 sustained glider operations are in place in the Ibiza and Mallorca channels. The data centre is the core of SOCIB. The data management system created for gliders is an example of the new informatics capabilities for real time definition of mission planning, including adaptive sampling and real time monitoring using a Web tool that allows quick visualization and download. This type of new infrastructures, combined with new technologies and careful scientific analysis will allow new ways of international cooperation leading to major science breakthroughs in the very near future and new ways of science based coastal and ocean management.