Biogeochemical impact of tropical instability waves in the equatorial Pacific - art. no. L24615 /Gorgues, T. /Menkès, Christophe /Aumont, Olivier /Vialard, Jérôme /Dandonneau, Yves Bopp, L. Tropical Instability Waves (TIW) have been suggested to fertilize the equatorial Pacific in iron leading to enhanced ecosystem productivity. Using a coupled dynamical-biogeochemical model, we show that contrary to this suggestion, TIWs induce a decrease of iron concentration by 10% at the equator and by about 3% over the Wyrtki box [90 degrees W-180, 5 degrees N-5 degrees S]. Chlorophyll decreases by 10% at the equator and 1% over the Wyrtki box. This leads to a decrease of new production up to 10% at the equator (4% over the Wyrtki box). TIW-induced horizontal advection exports iron-rich equatorial water to the north, but also brings iron-depleted water to the equator leading to a net decrease in iron. Additional iron decrease is caused by TIW-induced iron vertical diffusion. These two mechanisms are partly counter balanced by a decrease of iron biological uptake, driven by lower phytoplankton concentrations, and to a lesser extent by TIW-induced iron vertical advection. 2005 text https://www.documentation.ird.fr/hor/PAR00000704 PAR00000704 Gorgues T., Menkès Christophe, Aumont Olivier, Vialard Jérôme, Dandonneau Yves, Bopp L.. Biogeochemical impact of tropical instability waves in the equatorial Pacific - art. no. L24615. 2005, 32 (24), NIL_45-NIL_49 EN