Determinants of the Variance of Estimations on China's Carbon Emission: Based on Meta-analysis

China is confronting severe challenges to meet its rapidly increasing demand for energy and maintain its environments. It is well-known that China has become the world largest carbon emission country. However, there are huge different among different studies. As the accurate estimation of Carbon emission is critical and fundamental information for China's domestic policy and international negotiation. Based on the broaden and intensive literature reviews, the paper adopts a Meta-analysis method and the multi-factor variance analysis (ANOVA) to analyze the key factors that lead to the remarkable variations of estimations. Our results indicate the sources of researches and the choice of carbon emission coefficient affect the estimation significantly. The sources of researches, choice of carbon emission coefficient, energies classification and calculation based on national or provincial data are the four key determinants, accounting for 30.42%, 20.38%, 27.56% and 10.37% of variances of carbon emission estimations respectively. Interestingly, it is found that there is no significant difference among estimations based on industrial classification. According to our findings, it is proposed that the future studies to estimate China's carbon emission should pay extreme attentions on the detail classifications of energies and accuracy of carbon emission coefficient by different energies.