van Vuuren Detlef P, Doelman Jonathan C, Schmidt Tagomori Isabela, Beusen Arthur H W, Cornell Sarah E, Röckstrom Johan, Schipper Aafke M, Stehfest Elke, Ambrosio Geanderson, van den Berg Maarten, Bouwman Lex, Daioglou Vassilis, Harmsen Mathijs, Lucas Paul, van der Wijst Kaj-Ivar, van Zeist Willem-Jan
Netherlands Environmental Assessment Agency (PBL), The Hague, The Netherlands.
Copernicus Institute for Sustainable Development, Utrecht University, Utrecht, The Netherlands.
Nature. 2025 May;641(8064):910-916. doi: 10.1038/s41586-025-08928-w. Epub 2025 May 14.
The pressures humanity has been placing on the environment have put Earth's stability at risk. The planetary boundaries framework serves as a method to define a 'safe operating space for humanity' and has so far been applied mostly to highlight the currently prevailing unsustainable environmental conditions. The ability to evaluate trends over time, however, can help us explore the consequences of alternative policy decisions and identify pathways for living within planetary boundaries. Here we use the Integrated Model to Assess the Global Environment to project control variables for eight out of nine planetary boundaries under alternative scenarios to 2050, both with and without strong environmental policy measures. The results show that, with current trends and policies, the situation is projected to worsen to 2050 for all planetary boundaries, except for ozone depletion. Targeted interventions, such as implementing the Paris climate agreement, a shift to a healthier diet, improved food, and water- and nutrient-use efficiency, can effectively reduce the degree of transgression of the planetary boundaries, steering humanity towards a more sustainable trajectory (that is, if they can be implemented based on social and institutional feasibility considerations). However, even in this scenario, several planetary boundaries, including climate change, biogeochemical flows and biodiversity, will remain transgressed in 2050, partly as result of inertia. This means that more-effective policy measures will be needed to ensure we are living well within the planetary boundaries.
人类一直以来对环境施加的压力已使地球的稳定性面临风险。行星边界框架是一种界定“人类安全运行空间”的方法，迄今为止大多用于凸显当前普遍存在的不可持续环境状况。然而，评估长期趋势的能力有助于我们探究不同政策决策的后果，并确定在行星边界内生活的途径。在此，我们使用综合全球环境评估模型，针对到2050年的不同情景，对九个行星边界中的八个的控制变量进行预测，包括有无强有力环境政策措施的情况。结果表明，按照当前趋势和政策，预计到2050年，除了臭氧层损耗外，所有行星边界的状况都会恶化。有针对性的干预措施，如实施《巴黎气候协定》、转向更健康的饮食、提高食物以及水和养分利用效率等，能够有效降低跨越行星边界的程度，引导人类走向更可持续的轨迹（也就是说，如果这些措施能够基于社会和制度可行性考量得以实施）。然而，即便在这种情景下，到2050年仍有几个行星边界会被跨越，包括气候变化、生物地球化学流动和生物多样性，部分原因是存在惯性。这意味着需要更有效的政策措施来确保我们在行星边界内良好地生活。
