Inventory-Constrained Monthly Mapping of China’s Sectoral CO2 Emissions at 1 Km Using Earth Observation and Emission-Source Data

Kilometer-scale, sector-specific CO2 inventories support atmospheric modeling and regional mitigation. We developed an inventory-constrained monthly 1 km CO2 allocation product for China covering 2000–2024 and six sectors. Prescribed Emissions Database for Global Atmospheric Research (EDGAR) sector-month totals were conserved and spatially redistributed using sector-specific combinations of settlement, infrastructure, and emission-source data; the product therefore does not independently estimate aggregate emissions. Combined emissions increased from 3612.7 Mt CO2 in 2000 to 12,034.1 Mt CO2 in 2024, an increase of 233.1%. Evaluation against separate EDGAR gridmaps for 2024 assessed cell-magnitude agreement, spatial ranking, and top-10% hotspot overlap, but was only partially independent because of the shared EDGAR lineage. Buildings showed the strongest agreement within the residential benchmark scope (r = 0.906, ρ = 0.831; overlap = 70.6%), whereas power achieved only 12.0% positive-union overlap. Evaluations of transport and the industrial sectors were limited by benchmark compatibility. Comparison with the Global Emission Modeling System (GEMS) showed strong common-scope rank agreement (ρ = 0.834 in 2012 and 0.823 in 2021). The framework can be adapted to regions with compatible emission totals and spatial predictors, subject to region-specific evaluation.