| Summary: | 55 pages, 4 tables, 15 figures The eastern boundary of the North Atlantic subtropical gyre extends from the northern tip of the Iberian Peninsula at 43°N to south of Senegal at about 10°N, approximately the range of displacement of the Trade wind band (Fig. 23.1). It is one of the four major eastern boundary upwelling systems of the world ocean, and thus an area of intensive fisheries activity. The meridional shift of the Trade wind system causes seasonal upwelling in the extremes of the band, while in the central region upwelling is relatively continuous all year round (Wooster et al., 1976). Superimposed on the seasonal variation, short-term variability in wind direction and intensity may induce or suppress upwelling, affecting the dynamics of the ecosystem. At long-term scale, decadal fluctuations in fisheries landings - particularly north of 20°N- have been related to environmental changes due to the North Atlantic Oscillation (NAO) (Borges et al., 2003). In the southern part of the region, the influence of the El Niño Southern Oscillation (ENSO) may be also responsible of some of the recorded inter-annual variability in fisheries landings (Roy and Reason, 2001) This work was partially supported by the Spanish Plan Nacional de I+D (Projects COCA and MESOPELAGIC), the French IRD IDYLE project, the Portuguese Science Foundation (Projects SURVIVAL and PO-SPACC, and the programme PELAGICOS) and by the European Union (Projects “The Control of Phytoplankton Dominance”, “European Canaries-Coastal Transition Zone”, OMEX II, MORENA, CANIGO and OASIS). This is a contribution to the GLOBECSPACC program. EDB was partially funded by Mexican Conacyt Catedra Patrimonial EX-010009A No
|
|---|