Title
Intraseasonal variability of nearshore productivity in the Northern Humboldt Current System: The role of coastal trapped waves
Date Issued
01 February 2014
Access level
open access
Resource Type
journal article
Author(s)
Echevin V.
Albert A.
Lévy M.
Aumont O.
Piétri A.
Garric G.
Publisher(s)
Elsevier Ltd
Abstract
The impact of intraseasonal coastal-trapped waves on the nearshore Peru ecosystem is investigated using observations and a regional eddy-resolving physical-ecosystem coupled model. Model results show that intraseasonal variability over the period 2000-2006 represents about one fourth of the total surface chlorophyll variance and one third of the carbon export variance on the Peruvian shelf. Evidence is presented that subsurface nutrient and chlorophyll intraseasonal variability are mainly forced by the coastally trapped waves triggered by intraseasonal equatorial Kelvin waves reaching the South American coast, and propagate poleward along the Peru shore at a speed close to that of high order coastal trapped waves modes. The currents associated with the coastal waves induce an input of nutrients that triggers a subsequent phytoplankton bloom and carbon export. The impact of the local wind-forced intraseasonal variability on the ecosystem is of a similar order of magnitude to that remotely forced in the northern part of the Peru shelf on [50-90] day time scales and dominates over the entire shelf on [20-30] day time scales. © 2013 Elsevier Ltd.
Start page
14
End page
30
Volume
73
Language
English
OCDE Knowledge area
Ingeniería marina, naves Investigación climática
Scopus EID
2-s2.0-84889683524
Source
Continental Shelf Research
ISSN of the container
02784343
Sponsor(s)
Model simulations were computed using the NEC-SX8 Brodie, IBM cluster Vargas supercomputers from IDRIS ( http://www.idris.fr/ ) and the PC cluster network (adonis) from LOCEAN. A. Albert was funded by a scholarship of the French Ministère de l'Education et de la Recherche and by the Peru Ecosystem Projection Scenarios (PEPS) ANR-VMCS-2008 project. This work is a contribution to activities of the IRD-IMARPE DISCOH International Mixed Laboratory. Christian Ethé (IPSL) and Laurent Bopp (LSCE) are greatly acknowledged for providing outputs of the global ORCA2-PISCES coupled simulation. Pascal Terray (LOCEAN) is acknowledged for providing spectral analysis tools. Gildas Cambon (LEGOS) is acknowledged for implementing the online tracer diagnostics in the ROMS-AGRIF model. Xavier Capet, Francois Colas and Alban Lazar are acknowledged for fruitful discussions. Christophe Hourdin is acknowledged for technical support with ROMS-PISCES modeling. Four anonymous reviewers are acknowledged for their constructive and helpful comments.
Sources of information: Directorio de Producción Científica Scopus