The global carbon cycle is responsible for the distribution of carbon compounds on earth, most notably the carbon dioxide that not only helps to control the state of the Earth’s physical climate, but which serves as the source of carbon in photosynthesis that ultimately supports the existence of life on Earth. As human activities change distributions of carbon dioxide and other carbon-containing compounds, most notably, methane, the need to document the changes of concentrations of carbon-containing molecules in the atmosphere, understand their sources and sinks, together with the processes that couple the atmospheric, terrestrial, and oceanic parts of the global carbon cycle has never been greater. Significant advances in measurement capability, together with those for modeling approaches that can help interconnect observations of distributions of compounds to quantitative information about their sources and sinks, have the potential to be exceedingly useful in policy and decision making if they can be demonstrated to have sufficient accuracy, coverage, and resolution. In this session, presentations that address how observations and related modeling capabilities can be used to provide actionable information related to the sources and sinks of carbon-containing molecules in the Earth’s atmosphere.