Abstract: The IPCC assessment reports serve as important policy basis for the international society and national decision makers. Conclusions related to historical emission trends and future mitigation scenarios are the core subjects in IPCC WGIII report issued in April 2014, which will substantially influence the national positioning, mitigation responsibility allocation and national groupings in international negotiation, as well as global and national mid/long term mitigation targets setting and future global emission budget allocation. Based on comprehensive review and analysis of the key conclusions regarding historical emission trends and its drivers, emission budget and allocation, pathway, cost and technology choices under 2 degree target, etc. in the assessment report, this article further discuss the potential impacts of related conclusions on international climate change negotiation and domestic low-carbon development, as well as how to understand and apply these conclusions in decision making in an accurate and scientific manner.

Key words: climate change mitigation, IPCC, historical emission trends, mitigation scenarios, 2 degree target