Dissolved inorganic carbon in surface waters, the water column and sediment porewaters of the East Australian Current and Tasman Sea, RV Investigator voyage IN2016_V04

Full description

This collection contains dissolved inorganic carbon (DIC) measurements collected aboard RV Investigator during voyage IN2016_V04 in waters of the East Australian Current and Tasman Sea off eastern Australia. DIC was measured using an Apollo SciTech AS-C3 dissolved inorganic carbon analyser configured for semi-continuous underway measurements and analysis of discrete seawater samples.

The current dataset contains semi-continuous underway DIC measurements from the vessel's continuous surface seawater supply. Seawater was filtered through a 5 µm cartridge filter prior to DIC analysis. Temperature and salinity measured by the ship's underway CTD were used to calculate seawater density and express DIC concentrations in µmol kg⁻¹. A variable time offset between the DIC analyser and underway CTD records was manually estimated at approximately six-hour intervals and interpolated across the dataset before matching temperature and salinity to individual DIC measurements. The DIC system was calibrated approximately every 12 hours using Certified Reference Material supplied by A. G. Dickson, Scripps Institution of Oceanography, with DIC calculation and calibration following the AS-C3 operating procedures.

The collection is intended to include three components: semi-continuous underway surface-water measurements, discrete water-column measurements from CTD/Niskin samples, and sediment porewater measurements. Only the underway dataset is currently included. The discrete water-column and sediment porewater DIC data are undergoing quality-control review and will be added to the collection when that review is complete. Data access is currently restricted while the collection is being prepared for release.