Global greenhouse gas reconciliation 2022

This study compares the differences between the latest national greenhouse gas inventories (NGHGI) and atmospheric inversion models to support the global stocktake of the Paris Agreement. The comparison framework used includes net ecosystem exchange carbon dioxide (CO₂) flux, anthropogenic methane (CH₄) emissions, and anthropogenic nitrous oxide (N₂O) emissions. Our global harmonized NGHGI database was updated for inventory data by compiling data from periodical UNFCCC inventories by Annex I countries and sporadic and less detailed emissions reports by non-Annex I countries given by National Communications and Biennial Update Reports. For the inversion data, updated results from an ensemble of global inversions produced for the Global Carbon Project were used for the three greenhouse gases, with ancillary data. For CO₂, the updated CO₂ inversion ensembles up to 2021 included 3 new satellite inversions compared to the previous study, and an improved managed land mask was implemented. For CH₄ and N₂O, inversions are updated to 2020.