Thursday, 4:30 PM in 551 AB (RICC)
(subject to change)
By contrast with the northern region of the California Current System, during Spring 2005 the coastal waters off the north of the Baja California peninsula showed a nutrient enrichment which was registered off and within San Quintin Bay (SQB), a mediterranean-type coastal lagoon. During Spring 2004 nitrate concentrations at the oceanic stations showed a typical oscillation from high values (up to 14.7 micromolar) during an upwelling event to low values (down to 1.3 micromolar) during an upwelling relaxing stage. In Spring 2005 nitrate concentrations were persistently above 10 micromolar, and water was colder, saltier and CO2-richer than in 2004, suggesting an intensification of upwelling in 2005. Positive satellite-derived chlorophyll-a anomalies were observed for the whole of the northern coast of the Baja California peninsula during May-June 2005, which suggest that upwelling intensification was not local, but regional. Nitrate budgets for SQB using a box-model indicate that the supply of nitrate from the ocean to the lagoon was three times higher in Spring 2005 than in Spring 2004, indicating that the supply of nutrients from the ocean to estuarine systems along the NE Pacific coast of America can have intense interannual variations related not only to El-Niño / La Niña conditions.