Aller au contenu. | Aller à la navigation

Laboratoire d’Etudes en Géophysique et Océanographie Spatiales

Outils personnels

This is SunRain Plone Theme


Vous êtes ici : Accueil / Equipes de Recherche / SYSCO2 / _Abstracts / raimund_2011


Par dynbio — Dernière modification 28/11/2011 14:32

Sources of short-lived bromocarbons in the Iberian upwelling system


S. Raimund, B. Quack, Y. Bozec, M. Vernet, V. Rossi, V. Garçon, Y. Morel, and P. Morin

Biogeosciences, 8, 1551-1564, doi:10.5194/bg-8-1551-2011


Seawater concentrations of the four brominated trace gases, dibromomethane (CH2Br2), bromodichloromethane (CHBrCl2), dibromochloromethane (CHBr2Cl) and bromoform (CHBr3) were measured at different depths of the water column in the Iberian upwelling off Portugal during summer 2007. Statistical analysis of the data set revealed three distinct clusters, caused by different sea surface temperature. Bromocarbon concentrations were elevated in recently upwelled and aged upwelled waters (mean values of 30 pmol l−1 for CHBr3), while concentrations in the open ocean were significantly lower (7.4 pmol l−1 for CHBr3). Comparison with other productive marine areas revealed that the Iberian upwelling had higher halocarbon concentrations than the Mauritanian upwelling. However, the concentrations off the Iberian Peninsula were still much lower than those of coastal macroalgal-influenced waters or those of Polar regions dominated by cold water adapted diatoms. Correlations with biological variables and marker pigments indicated that phytoplankton was a source of bromocarbon in the open ocean. By contrast, in upwelled water masses along the coast, halocarbons showed weaker correlations to marker pigments but were significantly influenced by the tidal frequency. Our results indicate a strong intertidal coastal source of bromocarbon and transport by surface currents of these enriched waters towards the upwelling region.


-> Retour à la liste des publications

Actions sur le document