RAPID: US Geotraces N. Atlantic: Measuring the 13C-DIC distribution and quantifying the impact of organic matter export on 13C, nutrients and biologically active trace metals

University Of Washington, Seattle WA

Investigators

Abstract

With funding through a Grant for Rapid Response Research (RAPID), a research team at the University of Washington will participate in an originally unplanned oceanographic cruise in autumn 2011, as part of the U.S. GEOTRACES North Atlantic campaign to study carbon and oxygen isotopic signatures in the oceanic water column. The original, incomplete cruise (in autumn 2010) was terminated prematurely because of failure of the ship's propulsion system. The forthcoming follow-up cruise in 2011 will follow a track between Woods Hole, MA and Cape Verde Islands. These RAPID funds are being will cover only the costs of preparing for sample collection during the future cruise and not for laboratory analysis of the seawater samples or synthesis of the data. This team, originally supported through an ARRA award, will measure the same seawater characteristics on the future cruise as was proposed for the original cruise -- that is, the 13C/12C of dissolved inorganic carbon and the concentration of dissolved O2 and Ar gases. The scientific objectives have not changed; namely, they will quantify the rate of organic matter (OM) export using two separate methods that rely on the measured air-sea disequilibrium for del-13C and for dissolved O2 gas. The team will also determine the impact that OM export and its subsequent remineralization on the relationship between bioactive trace elements (BTE), del-13C-DIC and nutrient relationships in surface waters and at depth. Broader Impacts: Because these ocean carbon system data will become part of a multi-investigator international study, they will be made available to a worldwide community involved in the study of ocean chemistry and its relationship to global climatic change. Project results will also be incorporated into the principal investigator's teaching curricula, and the project itself will make provision for the participation of idergraduate students in the laboratory analytical work.