On the influence of topography in the induction of coastal upwelling alongthe Chilean coast

The contribution of the winds and the topography in the induction of upwell ing along the Chilean coastal zone is calculated. The topographic-induced u pwelling is estimated, taking into account the effect of the meridional cha nges of the coastline orientation. The wind-induced upwelling was calculate d for the austral summer using NSCAT scatterometer data, resulting a total amount of 2.1x10(6) m(3)s(-1) of water transported offshore for the whole C hilean upwelling zone. It is shown that the topographic effect dominates th e wind-induced upwelling in several parts of the Chilean coast, particularl y at 23 degreesS (Antofagasta), 25.5 degreesS, 30 degreesS (Coquimbo), 33 d egreesS (Valparaiso) and 37 degreesS (Concepcion). Antofagasta, Coquimbo, V alparaiso and Concepcion are well known zones of intense upwelling. The res ults show that the topography plays a key role in the upwelling of the Chil ean coast, specially in its northern part.