Winter upwelling recurrence along the Galician western coast

• Main Authors: Gómez-Gesteira, Moncho, Castro, Maite de, Álvarez, I., Crespo, A. J. C., Cabanas, José Manuel, Prego, R.
• Format: Conference Object
• Language: English
• Published: 2007
• Subjects: North Atlantic
• Online Access: http://hdl.handle.net/10261/330228

Symposium GLOBEC–IMBER España, Valencia, 28-30 marzo 2007 Upwelling events driving ENACW (Eastern North Atlantic Coastal Water) into the Galican western coast rias had been considered typical spring-summer processes, according to the research developed in this area. However, they can also be observed in fall or winter under northerly winds blowing at shelf. Six different upwelling events were analyzed in the Ria of Pontevedra during the wet season (NDJF) from 2000 to 2005. These events were characterized by means of the zonal Ekman transport (Qx) at four control points in front of the Western Rias (locally known as Rias Baixas) and the thermohaline variables measured at a fixed station in the main mouth of the Ria of Pontevedra. The duration of the upwelling events ranges from 27 days (during February and March 2002) to 69 days (during November, December 2004 and January 2005). Upwelling events studied in the Ria of Pontevedra from 2000 to 2005 show the similarity in upwelling features during both seasons (similar wind forcing and upwelled water). Finally, Qx was correlated with the most representative atmospheric patterns in the Northern Hemisphere (EA, NAO, EA/WR, POL and SCAND) from 1966 to 2005. The winter EA pattern has the most influence on Qx showing an annual evolution with a prevalence of the positive phase from 1976 on. This positive phase is directly correlated with a prevalence of positive values of Qx which are upwelling unfavorable in the Rias Baixas No