China's CO2 emissions: A systematical decomposition concurrently from multi-sectors and multi-stages since 1980 by an extended logarithmic mean divisia index

China's carbon dioxide (CO2) emissions have an important impact on global climate change. However, a systematical analysis, especially from the reform and opening up, is still insufficient. Thus, the emissions' decomposition since 1980 was completed by an extended logarithmic mean Divisia index (LMDI), concurrently from the perspectives of multi-sectors and multi-stages. The six sectors were (ⅰ) agriculture forestry animal husbandry and fishery (AF), (ⅱ) industry, (ⅲ) construction, (ⅳ) transport storage and post (TP), (ⅴ) wholesale and retail trades hotels and catering services (WRC), and (ⅵ) others. The four stages were 1980–1990, 1990–2000, 2000–2010 and 2010–2018. The results indicated that (1) China's CO2 emissions grew from 11.35 × 108 t in 1980 to 96.20 × 108 t in 2018 and the coal has produced the largest proportion. (2) The industry was the main source (79.83%) of total CO2 emissions. (3) The TP's energy and industrial structure and the AF's industrial structure showed a mitigating effect on the CO2 emissions' increase. The carbon emission coefficient presented a driving effect in 1980–1990 and the industrial structure also showed a mitigation effect in 2010–2018. Apart from these exceptions, the other factors' effects in each stage were consistent with the total effect. (4) Totally, the economic output showed the dominant driving effect (147.01%), followed by the population size (12.80%), energy structure (8.71%), and industrial structure (6.58%). Inversely, the energy intensity presented the clearest mitigation effect (−66.85%), followed by the carbon emission coefficient (−8.23%). These results obviously have guiding significances to the low-carbon emission of China's energy consumption.