Mapping the heterogeneity of global methane footprint in China at the subnational level

Abstract

Achieving the ambitious Global Methane Pledge announced in the Glasgow Climate Pact requires collaborative efforts from both the signatory countries and China which serves as the world's largest emitter. Considering the heterogeneity of economic structures within China and the relocation of emissions between regions via the global economic network, it is vital to investigate how China's methane emissions at the subnational level are linked to global final consumption. In this paper, we mapped global methane footprint in China from 2007 to2015 at the subnational level, by nesting China's interprovincial input-output tables into global multiregional input-output accounts and upscaling grid-level methane emission data of the Edgar database to the provincial level. Our results suggested that global methane footprint in China shifted westward, and the United States, European Union, Japan, and Hong Kong were the main drivers of China's local methane emissions. By illustrating the international and interprovincial trade flows of methane emissions, this study demonstrated that southeast coastal provinces were the hotspots for global methane footprint while middle inland provinces were the emission hotspots for China's domestic demands. We also showed how China's methane emissions were distributed through the nested global economic network to different economic agents. Moreover, emission trends of key exporting sectors for China's eight economic zones were detailed discussed. The outcome of this study may be fully supportive for identifying the heterogeneous effects of global methane footprint in China and implicative for interprovincial and international collaborations towards methane emission mitigation.

Keywords: Heterogeneous effects; International and interprovincial trades; Methane footprint; Nested MRIO table; Temporal-spatial changes.