On the accumulative contribution of CO2 emission from China to global climate change

A study of the contribution to global climate change from China’s COemission is conducted using the FIO-ESM v1.0 climate model. A series of sensitivity experiments are performed to identify two kinds of contributions to global climate change of China’s COemission due to fossil fuel combustion: one is the pure contribution which is the historical climate response from the sensitivity experiment forced only by China’s COemission, the other is the accumulative contribution which is proposed in this research and defined as the difference of historical climate responses between the experiments forced by all countries’ COemission and other countries’ COemission excluding China. The pure contribution approach considers the total COdischarged by China, while the accumulative contribution approach considers not only the discharge amount of China but also the discharge order of China and other countries. The latter is a more realistic approach to quantify the contribution of COemission to the historical change of atmospheric COconcentration, surface air temperature(SAT), sea surface temperature(SST) and sea ice coverage in the Arctic. Model results show that from the accumulative perspective, the ratio of the contribution of COemission from China for the increase of atmospheric COconcentration, SAT and SST, and the decrease of the sea ice coverage in the Arctic to that from all other countries excluding China varies from 8% to 92%, 5% to 95%, 9% to91% and 18% to 82%, respectively. Here we take the contribution of China’s COemission as an example, the contribution of COemission from any other country or area can be evaluated by the same approach.