A Standardized Intergovernmental Protocol for National Anthropogenic Gas-Flow Mass-Balance Accounting: Methodology, Algorithm, and Governance Framework

This paper presents a complete technical description of the deterministic algorithm underlying national greenhouse gas inventory accounting as specified in the IPCC 2006 Guidelines and 2019 Refinement. The protocol computes a single scalar balance for each reporting entity by applying standardized equations to measured activity data and fixed physical constants, yielding aggregate outflows minus aggregate inflows expressed in CO₂-equivalent. The paper documents the five-stage algorithmic sequence (general emission equation, fossil fuel combustion equation, land-stock-change removal equation, GWP conversion, and aggregation), the institutional governance process (government-nominated authorship, multi-round review, unanimous consensus adoption), the scope and boundary definitions (territorial, temporal, sectoral), the constants register with justification for fixity, and the extension framework (tiered implementation, uncertainty propagation, time-series consistency, QA/QC, notation keys). GWP values are presented from both the AR5 (current UNFCCC mandatory standard) and AR6 (latest science) assessment reports. The protocol is presented on its own terms as a purely technical mass-balance system. This paper serves as a companion methodological reference for a separate analytical work (Way, 2026, “Solvability Conditions in National Carbon Balance Accounting: The Folly of Universal Equilibrium Targets,” Zenodo, doi:10.5281/zenodo.18916673) that examines the structural properties of the balance equation when applied as a universal target. This paper contains no policy recommendations or external interpretations.