Determination of the effects of coastal-trapped waves on SST, phytoplankton pigment concentration and synoptic scale winds

Along the west coast of the Americas, sea levels and alongshore currents show large oscillations at intraseasonal periods (~30-80 days). Observations and theory have shown that many of these fluctuations are caused by coastal trapped waves, originated by equatorial Kelvin waves striking the west coast of Souther America.

Current and temperature records and CTD casts over the continental slope in northern and central Chile exhibit common, intraseasonal fluctuations of at least 10-15 cm/s near 220m depth and vertical isotherm displacements of at least serveral tens of meters near the thermocline. These oscillations are quite large perturbations in the coastal ocean and appear to be strongly modulating upwelling, influencing the nutrient concentration and the sea surface temperature variability near the coast.