Estimation of Chinese city-level anthropogenic methane emissions in 2015

Abstract China attaches great importance to methane (CH4) emissions, and the "14th Five-Year Plan" will formulate actions related to CH4 emission reduction. Accounting for and understanding CH4 emissions at the city level are of great importance because cities are the focus of future mitigation and adaptation activities to address climate change, especially in developing nations. However, existing studies have not yet provided a complete and updated emissions database of city-level CH4 emissions for China. To promote research on CH4 emissions accounting, this paper applies a production-based method to calculate anthropogenic CH4 emissions for 340 Chinese prefecture-level administrative units in 2015 based on multisource statistical information. The CH4 emission sources considered in this paper are mainly divided into five categories: underground coal mining, rice cultivation, livestock management, straw burning, and waste treatment. The results show that the characteristics of CH4 emissions in Chinese cities vary significantly and different emission sources present different spatial distribution characteristics. Moreover, there is an obvious single-source dominant pattern in the CH4 emission structure of Chinese cities. More than 50% of the total CH4 emissions in more than two-thirds of Chinese cities are from a single source. The accounting results are basically consistent with the official results, and the error range is within 20%, which is within the emission uncertainty range. The main contribution of this paper is the construction of a basic database to support China's efforts to achieve carbon neutrality by 2060.