ISA, School of Physics A28, The University of Sydney, Sydney, NSW, Australia.
Department of Environmental Systems Science, Institute for Environmental Decisions, ETH Zürich, Zürich, Switzerland.
Nat Commun. 2021 May 11;12(1):2676. doi: 10.1038/s41467-021-22884-9.
1.5 °C scenarios reported by the Intergovernmental Panel on Climate Change (IPCC) rely on combinations of controversial negative emissions and unprecedented technological change, while assuming continued growth in gross domestic product (GDP). Thus far, the integrated assessment modelling community and the IPCC have neglected to consider degrowth scenarios, where economic output declines due to stringent climate mitigation. Hence, their potential to avoid reliance on negative emissions and speculative rates of technological change remains unexplored. As a first step to address this gap, this paper compares 1.5 °C degrowth scenarios with IPCC archetype scenarios, using a simplified quantitative representation of the fuel-energy-emissions nexus. Here we find that the degrowth scenarios minimize many key risks for feasibility and sustainability compared to technology-driven pathways, such as the reliance on high energy-GDP decoupling, large-scale carbon dioxide removal and large-scale and high-speed renewable energy transformation. However, substantial challenges remain regarding political feasibility. Nevertheless, degrowth pathways should be thoroughly considered.
1.5°C 情景报告由政府间气候变化专门委员会（IPCC）报告，依赖于有争议的负排放和前所未有的技术变革的组合，同时假设国内生产总值（GDP）持续增长。到目前为止，综合评估模型界和 IPCC 一直忽视了去增长情景，在这种情景下，由于严格的气候缓解措施，经济产出下降。因此，它们避免依赖负排放和投机性技术变革速度的潜力仍未得到探索。作为解决这一差距的第一步，本文使用燃料-能源-排放关系的简化定量表示方法，将 1.5°C 去增长情景与 IPCC 原型情景进行了比较。在这里，我们发现与技术驱动的途径相比，去增长情景将许多关键的可行性和可持续性风险降到了最低，例如依赖于高能源-GDP 脱钩、大规模二氧化碳去除以及大规模和高速可再生能源转型。然而，在政治可行性方面仍面临重大挑战。尽管如此，去增长途径仍应得到充分考虑。
