Project: GEOTRACES: Intercalibration of Phosphate Oxygen Isotope Analyses and Sample Processing Techniques

Abstract:

The oxygen isotope composition of dissolved phosphate has the utility of tracing sources of this nutrient in continental shelf and upper slope environments, yield insights into remineralization mechanisms in the open ocean, and reveal biological turnover rates of phosphate. However, currently only a few published measurements are available. Inclusion of this parameter into the GEOTRACES Program would significantly enhance the data set but requires that his component be intercalibrated. For this reason, a scientist from the University of Chicago plans to collect and analyze water samples for the oxygen isotope composition of dissolved phosphate during the GEOTRACES intercalibration cruises to the Atlantic and Pacific Ocean. Once the analyses are completed, a set of recommendations on the best practices to obtain reliable measurements would be made accessible to the ocean sciences community. In addition, the researcher proposes to distribute samples and standards for the analysis of oxygen isotope composition of dissolved phosphate.

As regards broader impacts, this intercalibration effort could represent a first step towards the development of a new tracer for the ocean sciences community aimed at furthering our understanding of the phosphorus cycle.