||The vertical distributions of CO2, CH4, and other gases provide important constraints for the determination of terrestrial and ocean sources and sinks of carbon and other biogeochemical processes in the Earth system. While ground-based and satellite remote sensing instruments are being developed for this purpose, in-situ sampling and measurement is critical to validate the remote sensing. This collaboration between the DOE Biological and Environmental Research Program (DOE-BER) and the NOAA Earth System Research Laboratory (NOAA-ESRL), is quantifying the vertically resolved distribution of atmospheric carbon-cycle gases (CO2, CH4, and CO) throughout 99% of the atmospheric column. To accomplish these measurements, a long coiled tube (or Aircore) is lofted to the stratosphere (~ 30km) on a weather balloon, and then collects a vertically resolved sample of air on descent. In the first year of the project, we conducted six successful Aircore flights from the DOE ARM Southern Great Plains Facility in Oklahoma. In the coming year we plan to both conduct additional research flights for comparison with ARM and NASA remote sensing, and begin a transition from research-mode to operational balloon-borne sampling that includes semi-automated recovery and on-site gas analysis at ARM-SGP. The expected outcome of this project will be an operational capability providing data that supports key DOE science objectives.