Measurements of Variations in Atmospheric Oxygen/Nitrogen and Argon/Nitrogen Ratios, and Carbon Dioxide Concentration in Relation to the Carbon Cycle and Climate

University Of California-San Diego Scripps Inst Of Oceanography, La Jolla CA

Investigators

Abstract

This project supports the continuation of the measurement of the atmospheric oxygen/nitrogen (O2/N2) and argon/nitrogen (Ar/N2) ratios and carbon dioxide (CO2) mixing ratio in flask samples collected at ground-based stations around the world. These data will improve the characterization of sources and sinks of CO2 and provide a test bed for global models that describe carbon sequestration, particularly in relation to climate forcing, and will allow for early detection of any major shifts in carbon cycle function. The O2/N2 data are used for separating oceanic and terrestrial influences on atmospheric CO2. The atmospheric Ar/N2 ratio is sensitive mainly to thermally-induced ingassing and outgassing of Ar and N2 by the oceans. By constraining large-scale air-sea heat exchanges, the Ar/N2 measurements can provide an improved basis for understanding the oceans' role in the climate system, and for understanding climatic processes that influence the retention of CO2 in the atmosphere.