China has become the world’s largest carbon emitter. Its total carbon emission output from fossil fuel combustion and cement production was approximately 10 Gt CO_2 in 2013. However, less is known about carbon emissions from the production of industrial materials, such as mineral products (e.g., lime, soda ash, asphalt roofing), chemical products (e.g., ammonia, nitric acid) and metal products (e.g., iron, steel and aluminum). Carbon emissions from the production processes of these industrial products (in addition to cement production) are also less frequently reported by current international carbon emission datasets. Here we estimated the carbon emissions resulting from the manufacturing of 5 major industrial products in China, given China’s dominant position in industrial production in the world. Based on an investigation of China’s specific production processes, we devised a methodology for calculating emission factors. The results indicate that China’s total carbon emission from the production of alumina, plate glass, soda ash, ammonia and calcium carbide was 233 million tons in 2013, equivalent to the total CO_2 emissions of Spain in 2013. The cumulative emissions from the manufacturing of these 5 products during the period 1990–2013 was approximately 2.5 Gt CO_2, more than the annual total CO_2 emissions of India. Thus, quantifying the emissions from industrial processes is critical for understanding the global carbon budget and developing a suitable climate policy.
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