Paper - Belfer Center for Science and International Affairs, Harvard Kennedy School

Technology Factsheet: Solar Geoengineering

  • Bogdan Belei
| June 2019

Executive Summary

Solar geoengineering refers to a set of emerging technologies that could alter the Earth’s radiative balance—perhaps through injecting aerosols into the stratosphere, where they would reflect a small fraction of sunlight back into space—reducing the amount of climate change caused by greenhouse gases. It could not replace reducing emissions (mitigation), coping with a changing climate (adaptation), or carbon dioxide removal (CDR). Yet it does have the potential to supplement these efforts, and it might provide reductions in climate risk that are unachievable by other means. 


What is Solar Geoengineering?

Solar geoengineering has the potential to reduce climate impacts around the globe, but it also carries its own risks and uncertainties. The science and the governance are very challenging. The question at issue now is not about deployment. It is about whether there should be a serious research effort on solar geoengineering to advance understanding on the efficacy, benefits, and risks, and to identify strategies that might make it safer.

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For more information on this publication: Belfer Communications Office
For Academic Citation:

Lizzie Burns, David Keith, Peter Irvine, Joshua Horton. Ed. Bogdan Belei. “Technology Factsheet Series: Solar Geoengineering” Paper, Belfer Center for Science and International Affairs, Harvard Kennedy School, June 2019.


Bogdan Belei