Comparative analysis of anthropogenic CO2 emissions in Thailand using the ODIAC and CAMS datasets

Monitoring and managing greenhouse gas emissions in each country is essential to achieving the targets of the UNFCCC framework. Thailand has reported GHG emissions but lacks high resolution spatial emission data, which is crucial for identifying high concentration areas for management. The Open-Data Inventory for Anthropogenic Carbon dioxide (ODIAC) and the Copernicus Atmosphere Monitoring Service (CAMS) were compared with the national inventory provided by the Department of Climate Change and Environment (DCCE). Piecewise regression, spatial emission trend differences, ratios, and trend change indices were applied to investigate changes in emission time series, high emission areas, and emission trends. The results showed that emissions are approximately 2–3 times higher in ODIAC and less than 2 times higher in CAMS compared with the DCCE inventory. Emission trends were 19.68 MtCO2-eq/year, 15.55 MtCO2-eq/year, and 5.84 MtCO2-eq/year for ODIAC, CAMS, and DCCE, respectively. Both ODIAC and CAMS captured high emission areas, such as the Bangkok Metropolitan Region, but their emission trends during the latter sub-period differed in direction. Although differences exist in the characteristics of the datasets, they provide valuable information for GHG management. Harmonizing various datasets is required to improve comparability and ensure consistent interpretation.