Estimating Greenhouse Gas Emissions from Road Construction by Considering the Regional Differences in Carbon Emission Factors of Cement: The Case of China

Rapid road construction and expansion in China resulted in massive GHG emissions. The carbon emission factors of raw materials, particularly cement, have a significant influence on the calculation of GHG emissions from road construction. This study estimates GHG emissions from road construction by taking into account regional differences in cement carbon emission factors. The results indicate that (1) total GHG emissions from road construction have a "U" shape from 2009 to 2019, with the highest level being 437 million t CO(2)e 2009 and the lowest level being 184 million t CO(2)e in 2017; (2) Class-Ⅳ roads account for roughly 80% of total GHG emissions from road construction; and (3) GHG emissions from road construction are shifting from east to west regions. This is the first paper to calculate GHG emissions from road construction by taking into account both road type and cement carbon emission factors. The findings of this study could provide references for transportation agencies to better understand the impacts of road construction to climate change and improve policymaking, especially for the development of road construction technologies and raw material production technologies.