PBL Netherlands Environmental Assessment Agency, Bezuidenhoutseweg 30, NL-2594, AV, The Hague, the Netherlands.
Copernicus Institute of Sustainable Development, Utrecht University, Princetonlaan 8a, NL-3584, CB, Utrecht, the Netherlands.
Nat Commun. 2023 Jun 2;14(1):2949. doi: 10.1038/s41467-023-38577-4.
Despite its projected crucial role in stringent, future global climate policy, non-CO greenhouse gas (NCGG) mitigation remains a large uncertain factor in climate research. A revision of the estimated mitigation potential has implications for the feasibility of global climate policy to reach the Paris Agreement climate goals. Here, we provide a systematic bottom-up estimate of the total uncertainty in NCGG mitigation, by developing 'optimistic', 'default' and 'pessimistic' long-term NCGG marginal abatement cost (MAC) curves, based on a comprehensive literature review of mitigation options. The global 1.5-degree climate target is found to be out of reach under pessimistic MAC assumptions, as is the 2-degree target under high emission assumptions. In a 2-degree scenario, MAC uncertainty translates into a large projected range in relative NCGG reduction (40-58%), carbon budget (±120 Gt CO) and policy costs (±16%). Partly, the MAC uncertainty signifies a gap that could be bridged by human efforts, but largely it indicates uncertainty in technical limitations.
尽管在严格的未来全球气候政策中预计其将发挥关键作用，但非 CO2 温室气体（NCGG）减排仍然是气候研究中的一个重要不确定因素。对减排潜力的修订对实现《巴黎协定》气候目标的全球气候政策的可行性具有影响。在这里，我们通过综合文献综述，为 NCGG 减排的总不确定性提供了系统的自下而上的估算，制定了“乐观”、“默认”和“悲观”的长期 NCGG 边际减排成本（MAC）曲线。在悲观的 MAC 假设下，全球 1.5 度气候目标无法实现，在高排放假设下，2 度目标也无法实现。在 2 度情景下，MAC 不确定性导致相对 NCGG 减排（40-58%）、碳预算（±120 吉吨 CO）和政策成本（±16%）的预测范围较大。部分 MAC 不确定性表明这是人类努力可以弥补的差距，但主要还是表明了技术限制的不确定性。
