Global environmental challenges are progressively being mitigated through international collaboration, exemplified by treaties and agreements. Accurately estimating emissions of critical substances, such as greenhouse gases or synthetic ozone-depleting substances, and modeling their impact on the Earth system provide a scientific basis for international regulatory policymaking and compliance negotiations. This session invites contributions addressing: (1) quantification and verification of anthropogenic emissions from various sources, including direct fugitive emissions, production- and feedstock-related processes, banked emissions, and emissions from on-site “super-emitters”; (2) the role of these emissions in the Earth system, including climate, atmospheric chemistry, and feedback processes; (3) advances in reconciling discrepancies between top-down (observation-based) and bottom-up (process-based) estimates, including the use of in situ and satellite observations, improved monitoring in under-sampled regions, enhanced inventory methods (e.g., region-specific emission factors, facility-level data, and integration with observational constraints), and uncertainty reduction; and (4) implications for mitigation strategies, emissions tracking, and international compliance.

• GC - Global Environmental Change