Developing a passive trap for diffusive atmospheric ¹⁴CO₂ sampling

¹⁴C-CO₂ measurement is an unique tool to quantify source-based emissions of CO₂ for both the urban and natural environments. Acquiring a sample that temporally integrates the atmospheric ¹⁴C-CO₂ signature that allows for precise ¹⁴C analysis is often necessary, but can require complex sampling devices, which can be difficult to deploy and maintain, especially for multiple locations. Here we describe our progress in developing a diffusive atmospheric CO₂ molecular sieve trap, which requires no power to operate. We present results from various cleaning procedures, and rigorously tested for blank and memory effects. Traps were tested in the environment along-side conventional sampling flasks for accuracy. Results show that blank and memory effects can be minimized with thorough cleaning and by avoiding overheating, and that diffusively collected air samples agree well with traditionally canister-sampled air.