An important goal of the Multitracers Project is to quantify paleoproductivity (defined as organic carbon flux out of the euphotic zone) off the coast of Oregon from the peak of the last glacial maximum to the present. By accomplishing this goal the PIs will also develop paleoproductivity tracers that can be applied elsewhere in the oceans, and establish the limitations of each tracer. Three sediment trap moorings forming a transect away from the Oregon coast are a key aspect of the tracer calibration. The approach is to apply multiple tracers for productivity-the bulk organic fraction, inorganic elements (Cu,Zn,Ba), organic geochemical biomarkers, and microfossils-to determine when all give consistent information and to determine when each begins to track paleoceanogrphic variables other than productivity. Funding is provided for an additional field season for the Multitracers Project, consisting of two 6-month trap deployments at the two inshore sites. The high-solution sediment trap data and the water column information from the springtime should enable to adequately define winter-spring produtivity events in the region. In addition, the three-year time series of sediment trap fluxes will help understand the interannual variability of productivity in the California Current. This represents a modification to the previously-funded project entitled "Multitracers to predict paleoproductivity in the California Current System from sediment and sediment trap materials" (OCE-8609366).
