CO2 emissions embodied in China-US trade: Input-output analysis based on the emergy/dollar ratio

To gain insight into changes in CO2 emissions embodied in China-US trade, an input-output analysis based on the emergy/dollar ratio (EDR) is used to estimate embodied CO2 emissions; a structural decomposition analysis (SDA) is employed to analyze the driving factors for changes in CO2 emissions embodied in China's exports to the US during 2002-2007. The results of the input-output analysis show that net export of CO2 emissions increased quickly from 2002 to 2005 but decreased from 2005 to 2007. These trends are due to a reduction in total CO2 emission intensity, a decrease in the exchange rate, and small imports of embodied CO2 emissions. The results of the SDA demonstrate that total export volume was the largest driving factor for the increase in embodied CO2 emissions during 2002-2007, followed by intermediate input structure. Direct CO2 emissions intensity had a negative effect on changes in embodied CO2 emissions. The results suggest that China should establish a framework for allocating emission responsibilities, enhance energy efficiency, and improve intermediate input structure.Input-output analysis Emergy/dollar ratio Structural decomposition analysis