The latter carbon budget for the full century permits the budget to be temporarily overspent, as long as net-negative CO 2 emissions (NNCE) bring back cumulative CO 2 emissions to within the budget by 2100. 11 and contrast scenarios with a fixed remaining carbon budget until the time when net-zero CO 2 emissions (net-zero budget scenarios) are reached with scenarios that use an end-of-century budget design. We do this by adopting the scenario design from ref. Specifically, we explore mitigation pathways for reaching different temperature change targets with limited overshoot. We bring together nine international modelling teams and conduct a comprehensive modelling intercomparison project (MIP) on this topic. All these studies have relied on one or two models and/or a limited set of temperature targets. Some pioneering studies 10, 11, 12 have explored implications of limiting overshoot through, for example, zero emissions goals, or have looked into the role of bioenergy with carbon capture and storage (BECCS) in reaching different temperature targets 9. However, there has been critique that, with the exception of a few notable studies 9, 10, 11, 12, the scenarios in the literature first exceed the prescribed temperature limits in the hope of recovering from this overshoot later through net-negative emissions 13, 14, 15, 16. Studies explore aspects of the timing and costs of emissions reductions and the contribution of different sectors 3, 7, 8. 5) and its Special Report on Global Warming of 1.5 ☌ (SR1.5 ref. How such global temperature outcomes can be achieved has been explored widely in the scientific literature 1, 2, 3, 4 and assessed by the IPCC, for example, in its Fifth Assessment Report (AR5 ref. ![]() Within that context, countries are aiming to hold warming well below 2 ☌ and pursue limiting it to 1.5 ☌. The Paris Agreement sets the framework for international climate action. Even without net-negative emissions, CO 2 removal is important for accelerating near-term reductions and for providing an anthropogenic sink that can offset the residual emissions in sectors that are hard to abate. Our study further identifies alternative configurations of net-zero CO 2 emissions systems and the roles of different sectors and regions for balancing sources and sinks. We show that upfront investments are needed in the near term for limiting temperature overshoot but that these would bring long-term economic gains. Hence, we explore a new set of net-zero CO 2 emissions scenarios with limited overshoot. The current scenarios, however, are criticized because they feature strategies with pronounced overshoot of the global temperature goal, requiring a long-term repair phase to draw temperatures down again through net-negative emissions. Global emissions scenarios play a critical role in the assessment of strategies to mitigate climate change. ![]() Nature Climate Change volume 11, pages 1063–1069 ( 2021) Cite this article Cost and attainability of meeting stringent climate targets without overshoot
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