English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/25683
Compartir / Impacto:
Add this article to your Mendeley library MendeleyBASE
 |  Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL

Surface mixing and biological activity in the four Eastern Boundary Upwelling Systems

AutorRossi, Vincent ; López, Cristóbal ; Hernández-García, Emilio ; Sudre, Joel; Garçon, Véronique; Morel, Yves
Fecha de publicación27-ago-2009
EditorEuropean Geosciences Union
CitaciónNonlinear Processes in Geophysics 16(4): 557-568 (2009)
ResumenEastern Boundary Upwelling Systems (EBUS) are characterized by a high productivity of plankton associated with large commercial fisheries, thus playing key biological and socio-economical roles. Since they are populated by several physical oceanic structures such as filaments and eddies, which interact with the biological processes, it is a major challenge to study this sub- and mesoscale activity in connection with the chlorophyll distribution. The aim of this work is to make a comparative study of these four upwelling systems focussing on their surface stirring, using the Finite Size Lyapunov Exponents (FSLEs), and their biological activity, based on satellite data. First, the spatial distribution of horizontal mixing is analysed from time averages and from probability density functions of FSLEs, which allow us to divide each areas in two different subsystems. Then we studied the temporal variability of surface stirring focussing on the annual and seasonal cycle. We also proposed a ranking of the four EBUS based on the averaged mixing intensity. When investigating the links with chlorophyll concentration, the previous subsystems reveal distinct biological signatures. There is a global negative correlation between surface horizontal mixing and chlorophyll standing stocks over the four areas. To try to better understand this inverse relationship, we consider the vertical dimension by looking at the Ekman-transport and vertical velocities. We suggest the possibility of a changing response of the phytoplankton to sub/mesoscale turbulence, from a negative effect in the very productive coastal areas to a positive one in the open ocean. This study provides new insights for the understanding of the variable biological productivity in the ocean, which results from both dynamics of the marine ecosystem and of the 3-D turbulent medium.
Descripción12 pages, 4 figures.-- Published by Copernicus Publications on behalf of the European Geosciences Union and the American Geophysical Union.
Versión del editorhttp://dx.doi.org/10.5194/npg-16-557-2009
Aparece en las colecciones: (IFISC) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
NPGupwellings.pdf1,32 MBAdobe PDFVista previa
Mostrar el registro completo

NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.