By collecting up-to-date global emissions scenario results, we analyzed the range of global carbon budget of 2 ℃ and 1.5℃ target set by the Paris Agreement, and compared mitigation requirements of key time points, time of emission peaking and carbon neutral, and scales of negative emissions technologies application, of different emissions pathways. Compared to 2℃ target, global remaining carbon budget will be halved, more rapid mitigation will be required from 2020 onwards, and negative emissions technologies will be more heavily relied on. Delaying near-term mitigation action will strongly reduce future carbon budget, thus require deeper mitigation in mid and long term. Annual reduction rate will be required to increase by 1.2%, and net-zero emissions need to be reached 20years earlier; global carbon budget could be allocated to countries through different effort-sharing schemes. Regional distribution of global carbon budget is closely related to the chosen effort-sharing schemes. Resource-sharing schemes are more favourable for the United States and Europe, while burden-sharing ones are more favourable for China and India.%利用截止目前最新的全球情景研究结果,对《巴黎协定》提出的2℃和1.5℃目标下全球碳预算的区间进行分析,并比较了碳预算约束下不同排放路径对关键时间点的减排要求、实现排放峰值及碳中和的时间要求和对负排放技术的需求等方面的影响.结果表明:相对于2℃目标,1.5℃目标下全球剩余碳预算将缩减一半以上,2020年以后需要立刻快速减排,且到21世纪末更依赖于负排放技术的应用;延迟近期(2030年以前)的减排行动,将会使得2030年以后的碳排放空间被压缩,中长期的减排要求提高,2030~2050年间年均减排率增加约1.2%,实现碳中和的时间提前近20a,给未来的低碳转型带来更大困难;全球碳预算可以通过不同的公平分配方案分配到各国,其地区分布与公平分配方案的选择密切相关.排放量分配方案对美欧较为有利,而减排量分配方案对中印较为有利.
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