High-resolution mapping of transport CO₂ emission in Beijing-Tianjin-Hebei region: Spatial-temporal characteristics and decoupling effects

Numerous studies estimating transport CO2 emissions in developing countries were on the large scales and few provided high-resolution mapping of transport CO2 emissions from different transport modes according to their respective distribution and diffusion patterns. This study proposed a hybrid method for high-resolution mapping of transport CO2 emissions in metropolitan regions, and applied it to the Beijing-Tianjin-Hebei (BTH) region of China during 2000-2019. The results indicate that: (1) The transport CO2 emissions in the BTH region increased rapidly, of which road transport carbon emissions accounting for approximately 80%, air transport carbon emissions accounting for nearly 20%, railway and water transport accounted for a relatively small proportion. (2) For the transport CO2 emission structure from 2000 to 2019, road transport was still the main source, but its proportion has decreased since recent years, which air transport became the second largest source of emissions and had greater impact on Beijing and Tianjin. (3) The transport carbon emission hot spots were mainly located in Beijing and kept shrinking, while the cold spots were mainly located in the southern part of Hebei Province and kept expanding. (4) The decoupling relationship between county-level transport carbon emissions and economic growth changed from weak decoupling to expansive negative decoupling, showing a non-ideal development in the BTH region. Overall, this study revealed the spatiotemporal characteristics of transport CO2 emissions in the BTH region, based on which specific carbon reduction strategies could be promoted to facilitate sustainable low-carbon transport development in metropolitan regions in developing countries.