The ORNL DAAC recently released a datset from the Atmospheric Tomography (ATom) Mission developed by Morgan, E.J., et al. (2021):
This dataset provides O2/N2, CO2, Ar/N2, and stable isotope ratios of CO2 measured in flasks collected by the Medusa Whole Air Sampler. Flask measurements allow ground-truthing of onboard instrument measurements in a laboratory setting, where analysis conditions can often be more stringently controlled and carefully monitored. Medusa collected 32 cryogenically dried, flow, and pressure-controlled samples per flight. The samples are collected by an automated sampler into 1.5 L glass flasks that integrate over 25 seconds. Medusa flasks are analyzed on a sector-magnet mass spectrometer and a LiCor non-dispersive infrared CO2 analyzer by the Scripps O2 Program at Scripps Institution of Oceanography. Isotope and argon measurements can provide additional information about land and ocean controls over the carbon cycle and about the age and source of the air sampled.
ATom is a NASA Earth Venture Suborbital-2 mission to study the impact of human-produced air pollution on greenhouse gases and on chemically reactive gases in the atmosphere. ATom deployed an extensive gas and aerosol payload on the NASA DC-8 aircraft, including UCATS, for systematic, global-scale sampling of the atmosphere, profiling continuously from 0.2 to 12 km altitude. Around-the-world flights were conducted in each of four seasons between 2016 and 2018.
Additional data from ATom and other relevant links can be found on the ORNL DAAC's ATom Project Page.
Citation: Morgan, E.J., B.B. Stephens, J. Bent, A. Watt, S. Afshar, W. Paplawsky, and R.F. Keeling. 2021. ATom: L2 Trace Gas and Isotope Measurements from Medusa Whole Air Sampler, Version 2. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1881