To determine the temporal variations of the carbonate properties in the ocean during the EqPac time-series cruises.
Total CO (TCO) and total alkalinity (TA) will be measured by coulometry and potentiometry, respectively, on discrete water samples collected throughout the water column. Measurements of surface seawater CO partial pressure (pCO) in wet air are continuously monitored using an NDIR analyzer. These measurements are performed according to the recommended protocols described in the 1991 DOE handbook of methods for the analysis of the various parameters of the carbon dioxide system in sea water. TCO and TA measurements on a reference solution (provided by Andrew Dickson's laboratory) will be regularly performed at sea to facilitate the quality control of the data.
Our surface seawater pCO monitoring system (which also has the capability of measuring discrete samples) will be working also during the survey cruises, and will be used for intercalibration with the discrete measurements of pCO by GC that will be made during the survey cruises (by David Archer).