Ocean Carbon Chemistry Measurements from the AJAX_1983 Expedition

Chemical and physical oceanographic data were collected from the R/V Knorr in the North Atlantic, South Atlantic, and Southern Oceans between October 1983 and February 1984. The dataset includes measurements of dissolved inorganic carbon, alkalinity, carbon dioxide partial pressure, chlorofluorocarbons, nutrients, and temperature. These data were collected by Taro Takahashi of Columbia University's Lamont-Doherty Earth Observatory as part of the AJAX_1983 Expedition.

Use Cases

• Calibrating ocean carbon cycle models based on dissolved inorganic carbon and alkalinity measurements.
• Studying historical ocean ventilation and water mass ages based on chlorofluorocarbon (CFC-11, CFC-12) tracers.
• Analyzing nutrient distributions (nitrate, phosphate, silicate) in the Atlantic and Southern Oceans.
• Investigating air-sea carbon dioxide exchange based on partial pressure (fugacity) of CO2 measurements.

Strengths

• Data includes multiple key variables for carbon cycle studies, specifically listed as DIC, TA, pCO2, CFC-11, and CFC-12.
• Measurements cover a wide geographic range across three major ocean basins: North Atlantic, South Atlantic, and Southern Oceans.
• Data collection used specific, documented instruments including CTD, Coulometer, and flasks for discrete CO2 measurement.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Last updated 1984-02-19; freshness should be verified for contemporary applications.
• Row count is unknown, which may limit suitability assessment for large-scale analyses.

Provenance

Source

NOAA National Centers for Environmental Information (NCEI), originally from Columbia University; Lamont-Doherty Earth Observatory.

Collection Method

Discrete sample and profile observations collected using CTD, Coulometer for DIC measurement, and other instruments.

Time Range

1983-10-07 to 1984-02-19

Freshness

1984-02-19

Geography

North Atlantic Ocean, South Atlantic Ocean, Southern Oceans (> 60 degrees South)