Over the last few years, significant advances have been made in both in situ and remote sensing technologies for measuring greenhouse gases (GHGs). The launch of global observing systems (such as GOSAT, GOSAT-2, OCO-2, OCO-3, SMAP, TanSat, TROPOMI) as well as deployment of localized surface networks and aircraft field campaigns, is starting to yield more information on natural and anthropogenic sources than ever before. While these multiple observational platforms provide a significant potential for the monitoring of GHG emissions, more and more uncertainties are coming to light regarding our understanding of the global and regional budgets of GHGs, errors due to deficiency in atmospheric transport modeling, and identification and quantification of climate feedback sensitivities. This session solicits abstracts that provide new insights on understanding GHG dynamics at various spatial (local to global) and temporal (sub-diurnal to decadal) scales. We encourage contributions on: (a) current and prospective GHG observational studies that inform both the nature and impact of errors in transport due to convection and large-scale mixing, (b) modeling studies to quantify budgets and/or uncertainties in GHG flux estimates, and (c) evaluation and benchmarking of GHG estimates from Earth System Models using contemporary observations. Submissions that quantify GHG emissions at the urban scale and their uncertainties, or explore policy issues related to GHG monitoring and regulation and how the current state of the science is informing policy decisions, are highly encouraged.