Show simple item record

dc.creatorRUTLLANT,JOSÉ
dc.creatorMONTECINO,VIVIAN
dc.date2002-03-01
dc.date.accessioned2020-02-17T15:27:32Z
dc.date.available2020-02-17T15:27:32Z
dc.identifierhttps://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0716-078X2002000100020
dc.identifier.urihttps://revistaschilenas.uchile.cl/handle/2250/127426
dc.descriptionThe physical forcing of the upwelling along the subtropical west coasts of the continents encompasses a broad range of time scales which shape both phytoplankton biomass (Chl-a) and primary productivity (carbon fixation) changes over any given time interval. The narrow continental shelf and the steep alongshore orography off north-central Chile provide for a unique combination of year-round, upwelling-favorable winds with quasi-weekly upwelling pulses associated with atmospheric coastal-trapped disturbances (coastal lows). This variability is modulated by intraseasonal oscillations in the depth of the thermo/nutricline, produced by coastal-trapped waves in the ocean, upon which annual (seasons) and interannual (ENSO) cycles are superimposed. During coastal field experiments off Cruz Grande bay (29º S), carried on in November 1987 and 1988 (opposite extremes of the ENSO cycle), mean changes of the phytoplankton-integrated Chl-a (B) and carbon fixation rate (PP) from the active to the relaxed phases of the local upwelling forcing cycle (phyto-pattern) were characterized. Those data were contrasted against similar ones reported off Punta Lengua de Vaca (Coquimbo, 30º S) and off Mejillones peninsula (Antofagasta, 23º S), encompassing different seasons and phases of intraseasonal and interannual (ENSO) cycles from 1992 to 1997. A "warm" phyto-pattern was schematically characterized by a significant increase in B and a quasi-steady evolution of PP from the active to the relaxed phases of one complete upwelling event. Conversely, relative small changes in B and a significant increase in PP characterized a "cold" phyto-pattern. It is proposed here that the ENSO "cold/warm" signal may be offset by more than one opposite "thermal" condition (seasonal and/or intraseasonal) in defining a "warm" or "cold" phyto-pattern associated with a particular cycle of the local upwelling forcing
dc.formattext/html
dc.languageen
dc.publisherSociedad de Biología de Chile
dc.relation10.4067/S0716-078X2002000100020
dc.rightsinfo:eu-repo/semantics/openAccess
dc.sourceRevista chilena de historia natural v.75 n.1 2002
dc.subjectChile
dc.subjectcoastal upwelling
dc.subjectphytoplankton
dc.subjectlocal and remote upwelling forcing cycles
dc.subjectcoastal-trapped waves
dc.subjectENSO cycle
dc.titleMultiscale upwelling forcing cycles and biological response off north-central Chile


This item appears in the following Collection(s)

Show simple item record