He Haozhe, Soden Brian J, Vecchi Gabriel A, Yang Wenchang
High Meadows Environmental Institute, Princeton University, Princeton, NJ USA.
Rosenstiel School of Marine, Atmospheric and Earth Science, University of Miami, Miami, FL USA.
Commun Earth Environ. 2025;6(1):485. doi: 10.1038/s43247-025-02466-z. Epub 2025 Jun 20.
Stratospheric aerosol injection is a proposed method for offsetting greenhouse gas-induced warming by introducing scattering aerosols into the lower stratosphere to reflect sunlight. Here we explore a potentially more efficient alternative: weakening the Earth's greenhouse effect by deploying absorptive aerosols in the upper stratosphere (~10 hPa). These aerosols warm the carbon dioxide emission level-where outgoing longwave radiation is most sensitive to temperature-thereby enhancing top-of-atmosphere infrared emission without altering atmospheric carbon dioxide concentrations. Idealized climate model simulations indicate that this approach can reduce global temperatures an order of magnitude more efficiently per unit aerosol mass than conventional scattering-based interventions. Although based on simplified model experiments lacking interactive aerosol processes and operational constraints, our results identify a distinct physical mechanism for climate intervention, arguing for further research into the impacts-especially potential unintended side effects-of injecting absorptive aerosols into the upper stratosphere as an alternative solar radiation management strategy.
平流层气溶胶注入是一种通过将散射气溶胶引入平流层下部以反射阳光来抵消温室气体导致的变暖的提议方法。在此，我们探索一种可能更有效的替代方案：通过在平流层上部（约10百帕）部署吸收性气溶胶来减弱地球的温室效应。这些气溶胶使二氧化碳排放层变暖——在该层，向外的长波辐射对温度最为敏感——从而在不改变大气二氧化碳浓度的情况下增强大气顶层的红外辐射。理想化气候模型模拟表明，这种方法每单位气溶胶质量降低全球温度的效率比传统的基于散射的干预措施高一个数量级。尽管基于缺乏交互式气溶胶过程和运行限制的简化模型实验，但我们的结果确定了一种独特的气候干预物理机制，主张进一步研究将吸收性气溶胶注入平流层上部作为一种替代太阳辐射管理策略的影响——尤其是潜在的意外副作用。
