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There is a broad scientific consensus that SAI could quickly, efficiently, and cost-effectively reduce global temperatures down to pre-industrial levels.

Stratospheric aerosol injection (SAI) is the deliberate release of aerosols into the stratosphere to cool the Earth's surface. Discourse around SAI has grown in popularity over the past two decades in the face of inaction by world governments in addressing climate change mitigation, and it is often presented as a possible "quick fix" or "plan B" solution. Ignoring the large amount of risks and uncertainties, there is a broad scientific consensus that SAI could in principle effectively reduce global temperatures 1 2 3 4.

This potential cooling effect is based on well-understood physical processes observed in natural events, such as volcanic eruptions, the well-understood physics of aerosol light scattering, as well as substantial evidence from SAI computer climate modeling 4.

It should be noted that there are almost no voices in the scientific and geoengineering community that consider SAI as being without danger. Most researchers agree that SAI should not be attempted without strict safety measures and large-scale testing, and should only be a last resort when other mitigation options have been exhausted.

Sources​

Footnotes​

  1. Hulme, M. (2012). Climate change: Climate engineering through stratospheric aerosol injection. Progress in Physical Geography: Earth and Environment, 36(5), 694-705. https://doi.org/10.1177/0309133312456414 ↩

  2. Robock, A. (2016). Albedo enhancement by stratospheric sulfur injections: More research needed. Earth's Future, 4(12), 644-648. https://doi.org/10.1002/2016EF000407 ↩

  3. Crutzen, P. J. (2006). Albedo enhancement by stratospheric sulfur injections: A contribution to resolve a policy dilemma? Climatic Change, 77(3-4), 211-220. https://doi.org/10.1007/s10584-006-9101-y ↩

  4. National Academies of Sciences, Engineering, and Medicine. (2021). Reflecting sunlight: Recommendations for solar geoengineering research and research governance. National Academies Press. https://doi.org/10.17226/25762 ↩ ↩2