Comparison of the national-contributed emissions with the climate trace's global emissions inventory

Accurate and transparent greenhouse gas (GHG) inventories are vital for tracking global climate commitments. With advances in satellite technologies and AI-integrated platforms, alternative inventories like Climate TRACE have emerged as complements or replacements for traditional systems such as the UNFCCC. This study compares GHG emissions reported by Climate TRACE and UNFCCC country submissions for 2015–2021. Eight countries—Australia, Belgium, Brazil, Germany, Japan, Poland, Turkey, and the United States—were selected for their data availability and regional diversity. Percentage differences between the two datasets were calculated for 13 sectors, and methodological consistencies were assessed using Principal Component Analysis (PCA) and K-means clustering. A heatmap visualization illustrated percentage differences across sub-sectors, highlighting areas of agreement and divergence. Results show substantial differences across most countries and sectors, with Climate TRACE often reporting higher emissions. The Waste sector and certain LULUCF sub-sectors had the largest discrepancies, largely due to methodological, scope, and data granularity differences. Climate TRACE's satellite- and AI-based methods—such as flaring inefficiency models, wastewater plant detection, and forest degradation monitoring—contributed to these gaps. Conversely, sectors like Enteric Fermentation in some countries (e.g., Belgium) showed higher alignment where Climate TRACE applied standard IPCC methodologies. The findings underscore how methodological heterogeneity—between and within inventories—affects comparability, highlighting the need for transparent methods and consistent sectoral definitions to improve global climate accountability.