ATom Mission Global Atmospheric Trace Gas and Isotope Measurements

32 cryogenically dried air samples were collected per flight by NASA's Atmospheric Tomography mission using the Medusa Whole Air Sampler on a DC-8 aircraft. The dataset provides O2/N2, CO2, Ar/N2 ratios and stable isotope measurements (13C, 14C, 18O) of CO2 from global-scale atmospheric profiling between 0.2 and 12 km altitude. Samples were analyzed by the Scripps O2 Program using a sector-magnet mass spectrometer and a LiCor CO2 analyzer.

Use Cases

• Calibrating and validating in-situ O2/N2 and CO2 measurements from continuous airborne instruments.
• Investigating regional sources and sinks of CO2 using stable isotope ratios (δ13C, δ18O).
• Studying atmospheric oxygen trends and air-sea gas exchange via precise O2/N2 and Ar/N2 ratio measurements.
• Analyzing seasonal and vertical gradients of trace gases across four global campaigns from 2016 to 2018.

Strengths

• Provides unique, co-located measurements of Ar/N2 and multiple CO2 isotopologues (13C, 14C, 18O) not commonly available together.
• Samples were collected with controlled cryogenic drying, flow, and pressure for high data integrity.
• Covers a wide vertical range (0.2-12 km) and four seasonal campaigns, offering a 3D global perspective.

Limitations

• Exact row count and column names are not provided in the available metadata.
• Conflicting last update dates exist between platforms (2018-05-21 on NASA Earthdata and 2026-03-13 on Data.gov).
• License is specified as 'other-license-specified' without explicit details on Data.gov.

Provenance

Source

Scripps O2 Program, Scripps Institution of Oceanography, for NASA's Atmospheric Tomography (ATom) mission.

Collection Method

Airborne collection via automated Medusa Whole Air Sampler into 1.5L glass flasks with 25-second integration, followed by lab analysis using mass spectrometry and non-dispersive infrared analysis.

Time Range

2016 to 2018

Freshness

2026-03-13 14:00:01.938803

Geography

Global-scale sampling across multiple flight tracks covering all major ocean basins and continents.