Pathway optimization of China's carbon emission reduction and its provincial allocation under temperature control threshold

As the largest carbon emitter in the world, China faces great pressure to fulfill the temperature control targets, i. e., 2 degrees C and 1.5 degrees C, proposed in the Paris Agreement. Thus, selecting a development path that could both meet the temperature targets and economic growth is essential and worth investigating. We propose an optimization model to analyze China's carbon dioxide emission paths from 2010 to 2050 in three scenarios, namely baseline, and 1.5 degrees C and 2 degrees C target scenarios. The marginal cost of carbon abatement in China's 30 provinces (excluding Hong Kong, Macao, Taiwan, and Tibet) were also calculated using the quadratic directional distance function model, and the quotas of carbon dioxide emission among provinces were allocated. Carbon dioxide emission peak will occur in 2040 under the 2 degrees C target scenario and in 2030 under the 1.5 degrees C target scenario. The marginal cost of carbon abatement to achieve the 1.5 degrees C goal is approximately 1.6 times more expensive than the 2 degrees C goal. We suggest to implement emission reduction policies in the Eastern coastal areas of China and to allocate greater carbon dioxide emission quotas in under-developed areas in the Central and Western regions. Provincial quota allocation may also help to balance regional development and achieve the mutually beneficial goal of economic growth and carbon emission reduction in China. Our findings provide practical guidance on achieving carbon dioxide emission reduction and critical enlightenments on policymaking.