Measurement of Fugacity of Carbon Dioxide in Seawater: An Evaluation of a MethodBased on Infrared Analysis

摘要

An analysis system is described to measure the fugacity of CO2(fCO2)1 in 500ml ofseawater (discrete samples) by infrared analysis. The units is used on oceanographic research cruises sponsored by the Ocean-Atmosphere Carbon Exchange Study (OACES) of NOAA since 1991 for a total of approximately 10,000 measurements. The precision of the analyses based on replicate samples during routine analysis is 0.2%. Precision is primarily limited by sample storage, and the difference between headspace gas and water CO2 concentrations prior to equilibration.