Compilation of an Embodied CO2 Emission Inventory for China Using 135-Sector Input-Output Tables

A high-quality carbon dioxide (CO2) inventory is the cornerstone of climate change mitigation. Most of the previously reported embodied CO2 inventories in China have no more than 42 sectors, and this limitation may introduce apparent inaccuracy into the analysis at the sector level. To improve the quality of input-output (IO)-based CO2 inventories for China, we propose a practical energy allocation approach to link the energy statistics to the 135-sector IO tables for China and compiled a detailed embodied CO2 intensity and inventory for 2007 using a single-region IO model. Interpretation of embodied CO2 intensities by fuel category, direct requirement, and total requirement in the sectors were conducted to identify, from different perspectives, the significant contributors. The total embodied CO2 emissions in 2007 was estimated to be 7.1 Gt and was separated into the industrial sector and final demand sector. Although the total CO2 estimations by the 42-sector and 135-sector analyses are equivalent, the allocations in certain groups of sectors differ significantly. Our compilation methodologies address indirect environmental impacts from industrial sectors, including the public utility and tertiary sectors. This method of interpretation could be utilized for better communication with stakeholders.