Recent improvements in mesoscale characterization of the western Mediterranean Sea: synergy between satellite altimetry and other observational approaches

Abstract

SUMMARY: Satellite altimetry is a key component of the global observing system and plays a major role in the study of the mesoscale processes that drive most of the ocean circulation variability at middle and high latitudes. However, satellite altimetry alone provides only surface information at a limited spatio-temporal resolution. To address these limitations and to better describe the mesoscale three-dimensional variability, it is necessary to complement altimetry data with additional remote and in situ measurements. This study provides an update of the recent advances in the study of the mesoscale variability using a combination of altimetry and other independent observations, with an emphasis on the results obtained for the western Mediterranean Sea. The circulation in this area is complex because of the presence of multiple interacting scales, including basin-scale, sub-basin-scale and mesoscale structures. Thus, characterizing these processes requires highresolution observations and multi-sensor approaches. Accordingly, multi-platform experiments and analyses have been designed and undertaken in the different sub-basins of the western Mediterranean Sea. These studies have demonstrated the advantages of synergetic approaches that use a combination of observation techniques and are able to resolve different spatiotemporal scales with the aim of better understanding mesoscale dynamics.Keywords: satellite altimetry, mesoscale variability, instruments and techniques, Mediterranean Sea. RESUMEN: AvAnces recientes en lA cArActerizAción de lA mesoescAlA en lA cuencA mediterráneA occidentAl: sinergiAs entre AltimetríA y otros sistemAs de observAción. -La altimetría satelitaria es una componente clave del sistema de observación global y juega un papel importante en el estudio de los procesos de mesoescala que impulsan la mayor parte de la variabilidad de la circulación oceánica en las latitudes medias y altas. Sin embargo, la altimetría por satélite sólo proporciona información superficial y con una resolución espacio-temporal limitada. Para hacer frente a estas limitaciones, es necesario complementar los datos de altimetría con otras medidas. Este estudio proporciona una actualización de los avances recientes en el estudio de la variabilidad de mesoescala utilizando una combinación de observaciones altimétricas con otros datos independientes en el Mediterráneo Occidental. La circulación en esta zona es compleja debido a la presencia de múltiples escalas interactuando entre ellas: cuenca, sub-cuenca y estructuras de mesoescala. Por tanto, la caracterización de estos procesos requiere de alta resolución en las observaciones y de enfoques multi-sensoriales. En este trabajo, presentamos una revisión de diversos experimentos multi-plataforma que se han diseñado y llevado a cabo en los diferentes sub-cuencas del Mediterráneo occidental durante los últimos años. Estos estudios han demostrado las ventajas de los enfoques sinérgicos y métodos innovadores que utilizan una combinación de técnicas de observación, y que son ca...

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