NAC13v1: Del13C-DIC Isotope Data for the North Atlantic

NCEI accession 0164569 provides an internally consistent dataset of Del13C-DIC (carbon-13 isotope) measurements from dissolved inorganic carbon in the North Atlantic Ocean. The dataset contains 6569 samples collected during 32 oceanographic research cruises between 1981 and 2014. Data underwent a two-step quality control process, including crossover analysis to quantify and adjust for systematic biases between cruises.

Use Cases

• Calibrating ocean carbon cycle models based on the quality-controlled Del13C-DIC time series.
• Studying long-term trends in carbon isotope fractionation using data spanning over three decades.
• Assessing the internal consistency of ocean carbon measurements via the documented crossover analysis methodology.
• Linking cruise data to broader synthesis projects like GLODAPv2 and CARINA using the provided EXPOCODE mapping.

Strengths

• Contains 6569 individual Del13C-DIC samples, providing substantial observational density.
• Underwent a documented two-step quality control process, with an estimated internal consistency of 0.017 o/oo.
• Covers a long temporal range from 1981 to 2014, enabling analysis of multi-decadal trends.
• Includes explicit quality flags ('Del13Cf', 'Del13Cqc') for each data point.

Limitations

• Specific column names beyond the flags are not listed in the provided metadata, limiting understanding of the full data structure.
• Conflict in 'last updated' metadata: one source lists 2014-12-12, while another lists 2026-03-05, creating uncertainty about recent maintenance.
• Only 24 of the 32 cruises were quantitatively comparable for bias analysis, and adjustments were applied to 11 of those.

Provenance

Source

National Oceanic and Atmospheric Administration (NOAA), Department of Commerce.

Collection Method

Samples collected during oceanographic research cruises; data compiled and quality-controlled by NCEI.

Time Range

1981 to 2014

Freshness

2026-03-05 23:38:48.694540 (conflict with 2014-12-12 date from another source)

Geography

North Atlantic Ocean