Trace Gas Measurements from WAIS-Divide Ice Core Samples

Gases in Firn Air and Shallow Ice at the Proposed WAIS Drilling Site contains trace gas measurements from 57 ice core samples from the West Antarctic Ice Sheet Divide A core. The dataset includes mixing ratios for nine trace gas species: ethane, propane, n-butane, carbonyl sulfide, carbon disulfide, methyl chloride, methyl bromide, acetonitrile, and chlorofluorocarbon-12. Analyses were conducted by the University of California, Irvine on samples dry-drilled during the 2005-2006 field season.

Use Cases

• Analyze the relationship between mixing ratios of methyl chloride (CH3Cl) and methyl bromide (CH3Br) to study halogen source variability in the paleo-atmosphere.
• Compare the temporal record of carbonyl sulfide (COS) and carbon disulfide (CS2) levels across the 57 samples to investigate sulfur compound cycling.
• Assess the atmospheric preservation fidelity of chlorofluorocarbon-12 (CFC-12) in Antarctic ice by examining its concentration profile.
• Investigate the correlation, if any, between light alkane species (ethane, propane, n-butane) and acetonitrile (CH3CN) to identify potential non-atmospheric sources or artifacts.

Strengths

• 57 distinct ice core samples analyzed for trace gas content.
• Nine specific trace gas species measured per sample, providing a multi-species profile.
• Data originates from a well-documented, dry-drilled core (WAIS-D 05A) from a key Antarctic site.

Limitations

• The dataset is preliminary and unpublished, with mixing ratios potentially impacted by analytical or sampling artifacts.
• Small sample size of 57 cores may limit statistical power for detecting subtle trends.
• The authors caution against interpreting light alkane and CH3CN data as reliable paleo-atmospheric records, as there are no prior published ice core records for these compounds.

Provenance

Source

University of California, Irvine, via the SCIOPS organization and NASA Earthdata.

Collection Method

Gas chromatography/mass spectrometry analysis of air extracted from dry-drilled ice core samples.

Time Range

Samples collected during the 2005-2006 Antarctic field season.

Freshness

Data last updated in January 2006; represents a snapshot from the 2005-2006 field season.

Geography

West Antarctic Ice Sheet Divide (WAIS-D) drilling site, Antarctica.