A SIGNATURE OF THE LOW FREQUENCY VARIABILITY ON THE
BIOGEOCHEMICAL FEATURES OF THE NORTHERN HUMBOLTH UPWELLING
ECOSYSTEM
Graco Michelle1, Ledesma Jesús1, Purca Sara1, Dewitte Boris2, Castro Carmen3,
Flores Georgina1Morón Octavio1and Dimitri Gutiérrez1
The Northern Humboldt Current Upwelling Ecosystem and particularly off Perú, isa “hot
spot” for scientist around the world because of their unique characteristics and also
paradigms, a high productivity and efficient trophic transfer, one of the intense and
acidic Oxygen Minimum Zone (OMZ) and one of the nitrogen lost areas. All these
features are under the impact of several temporal variability scales, as the strong
interannual variability associated with the Equatorial remote forcing.In this context, we
examined the oceanographic and biogeochemical variability off Central Perú, from a
monthly time-series (1996–2009). We present evidences that the Equatorial
Intraseasonal Kelvin waves appear to modulate the distribution of the OMZ in the area
and in consequence affecting the chemical structure and biogeochemical activity in the
system, not only at interannual but also intraseasonal time scale. These changes could
have a deep impact in productivity,carbon and nitrogen loss.
1. Instituto del Mar del Perú (IMARPE), P.O. Box 22, Callao, Perú. Dirección de
Investigaciones Oceanográficas.
LMI
DISCOH
(WP3)
IMARPE-IRD.
2.
Laboratoired`Etudes en Géophysique et OcéanographieSpatiale (LEGOS), Toulouse,
France 3. CSIC, Instituto de Investigaciones Mariñas, Eduardo Cabello 6, 36208 Vigo,
Spain.