Dissolved Trace Metal Concentrations over the Peru Shelf and in the Subsurface Oxygen Minimum Zone Off Peru

Abstract:

The Peru coast is the site of one of the largest fisheries in the world, and home to some of the highest f-ratios ever recorded. As a result of this highly productive surface water, an intense subsurface oxygen minimum zone (OMZ) persists. Despite the import of the effect of OMZs due to their predicted increase with global warming, there is very little trace metal data from this region. Here we present dissolved trace metal data from the U.S. GEOTRACES Eastern Pacific Zonal Transect over the Peru shelf and through the OMZ. Results suggest a sink of Pb, Cd, Sc, Cu and Ga in the suboxic region of the shelf, and a shelf source of Co and Fe. Trace metal concentrations within the OMZ will also be discussed. As many of these metals have not been analyzed in this region previously, this work can serve as a baseline for future comparison and adds to the understanding of global trace metal distributions.