[en] In the framework of the Canaries‐Iberian marine ecosystem Exchanges (CAIBEX) experiment, an interdisciplinary high‐resolution survey was conducted in the NW African region of Cape Ghir (30°38′N) during August 2009. The anatomy of a major filament is investigated on scales down to the submesoscale using in situ and remotely sensed data. The filament may be viewed as a system composed of three intimately connected structures: a small, shallow, and cold filament embedded within a larger, deeper, and cool filament and an intrathermocline anticyclonic eddy (ITE). The cold filament, which stretches 110 km offshore, is a shallow feature 60 m deep and 25 km wide, identified by minimal surface temperatures and rich in chlorophyll a. This structure comprises two asymmetrical submesoscale (∼18 km) fronts with jets flowing in opposite directions. The cold filament is embedded near the equatorward boundary of a much broader region of approximately 120 km width and 150 m depth that forms the cool filament and stretches at least 200 km offshore. This cool region, partly resulting from the influence of cold filament, is limited by two asymmetrical mesoscale (∼50 km) frontal boundaries. At the ITE, located north of the cold filament, we observe evidence of downwelling as indicated by a relatively high concentration of particles extending from the surface to more than 200 m depth. We hypothesize that this ITE may act as a sink of carbon and thus the filament system may serve dual roles of offshore carbon export and carbon sink.
Disciplines :
Earth sciences & physical geography
Author, co-author :
Sangrà, Pablo; Universidad de Las Palmas de Gran Canaria
Troupin, Charles ; Sistema d’observació i predicció costaner de les Illes Balears (SOCIB) > Data Center Facility
Barreiro-González, Beatriz
Barton, Eric Desmond; Instituto de Investigaciones Marinas (CSIC)
Orbi, Abdellatif
Arístegui, Javier; Universidad de Las Palmas de Gran Canaria
Language :
English
Title :
The Cape Ghir filament system in August 2009 (NW Africa)
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