Improving carbon emission estimates through data fusion: Evidence from China’s construction industry

Reliable carbon emission estimates are fundamental to designing effective climate mitigation policies. As one of the largest emitters in China, the construction industry attracts considerable attention. However, prevalent outliers in construction material statistics undermine emission estimates. This study enhances carbon emission estimates in China's construction industry during 2004-2021 using a data fusion approach. The results indicate that outliers caused a cumulative overestimation of 7,396 million tonnes (Mt), concentrated in 2011-2014 and 2019. Pre-correction data suggest a 2012 peak at 5,337 Mt, yet corrected estimates demonstrate overall growth through 2021, reaching 4,380 Mt. After correction, emissions grew at 16.2% annually during 2004-2014 and then slowed to 3.4% annually. Cement share decreased from 58.4% to 43.0%, while steel increased from 25.0% to 33.6%. Provincial intensity varied 5.2-fold. The data fusion approach can be applied to other sectors or countries facing similar data challenges, helping policymakers to better understand actual emission trajectories.