title: Twelve years of change in coastal upwelling along the central-northern coast of Chile: spatially heterogeneous responses to climatic variability.
abstract: We use time-series analyses to characterize the effects of recent climate variability upon the local physical conditions at 11 study sites along the northern-central coast of Chile (29-34°S). Environmental indices show that the 1° Bakun upwelling index in this coastal region has fluctuated in time, starting from a stable period around the 1980's, peaking during the mid 90s, decreasing during the next ten years and increasing at a steep rate since 2010. Upwelling intensity decreased with increasing latitude, showing also a negative correlation with climate patterns (El Niño3 sea surface temperature-SST anomalies and the Multivariate El Niño Index). We hypothesize that the impacts of climate variability on upwelling events seem to be spatially heterogeneous along the region. Non-sheltered locations and, particularly, sites on prominent headlands show an immediate (lag = 0) and negative correlation between local SST, upwelling events and wind stress. We suggest that near-shore thermal conditions are closely coupled to large-scale forcing of upwelling variability and that this influence is modulated through local topographic factors.
authors.affiliation: Centro de Estudios Avanzados en Zonas Áridas, Facultad Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Aravena
authors.affiliation: Centro de Estudios Avanzados en Zonas Áridas, Facultad Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile.
authors.forename: Bernardo
authors.initials: B
authors.lastname: Broitman
authors.affiliation: Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway.
authors.forename: Nils Christian
authors.initials: NC
authors.lastname: Stenseth
mesh_terms: D002677:Chile; D059000:El Nino-Southern Oscillation; D009792:Oceans and Seas; D012621:Seasons; D062211:Spatio-Temporal Analysis; D013696:Temperature; D014872:Water Movements; D014919:Wind