Abstract: Long-term climate change mitigation target would highly constrain global carbon emissions in future. Carbon permit allocation under the long-term mitigation target would impact development space for all countries, involving the fundamental interests. Some developed countries advocate the principle of per capita emission convergence while China and other developing countries propose the principle of convergence of accumulative emission per capita to consider historical responsibility. If the latter is used for carbon permit allocation, CO₂ emissions of developed countries since the industrial revolution have far exceeded their allocated permits. Developed countries?high per capita emissions at present and for quite a long period in future would continue to occupy emission spaces for developing countries. Therefore, developed countries must commit deeper emission reduction rate for the next commitment period at the Copenhagen conference in order to achieve the emission pathway under the long-term emission reduction target, and to save necessary development space for developing countries. At the same time, developed countries should provide adequate financial and technical support as compensation for their overuse of the development space for developing countries, to improve developing countries?capacity to respond to climate change under the framework of sustainable development. On the one hand, we should insist on the principle of equity to obtain reasonable emission space for our country in the international climate change negotiation; while on the other hand, we should enhance development toward low-carbon economy to protect global environment and to achieve sustainable development.

Key words: climate change, carbon permit allocation, long-term mitigation target, accumulative emission per capita, Copenhagen conference