Mapping a High-Resolution Anthropogenic CO2 Emissions Inventory at City-Level Using Point-Line-Area Method

As the hotspots of population, energy consumption and economic activities, cities contribute > 70% anthropogenic CO2 emissions, and have become key areas for emission reduction and tackling climate change. Understanding city’s CO2 emissions is a prerequisite and a fundamental step in formulating strategies to achieve net-zero emissions target before 2060. Chongqing is one of the four municipalities, which plays a critical guiding and exemplary role in promoting Chinese city carbon emissions reduction. However, the high-resolution spatial characteristics and driving forces of anthropogenic CO2 emissions in Chongqing are still not well understood. Here, we compiled a 1 km × 1 km high-resolution gridded CO2 emission data based on point, line, and area emission sources, including accurate geographical locations and emissions of 1949 enterprises, four types of traffic roads with different weighting factors, and activity data collected from the statistical yearbook at district and county scales. Results showed that the total CO2 emissions of Chongqing was 160 million tonnes (Mt) in 2020, of which more than 70% emissions were agglomerated in the urban areas. Energy consumptions are responsible for a considerable part (82%) of the total emissions. These findings improve our understanding of site-specific, sectoral, and county-level anthropogenic CO2 emissions in Chongqing, as well as providing a key input for carbon monitoring and atmospheric inversion to support carbon peaking and carbon neutral assessment.