Miranda Hack provides an in-depth look at the often-overlooked engineering and logistical barriers to large-scale deployment of solid particles for stratospheric aerosol injection (SAI). She explains how dispersing sub-micron mineral particles at altitude, including challenges like agglomeration, complex nozzle flows, and supply-chain constraints, introduces significant uncertainties and costs. These challenges may reduce cooling efficiency and narrow the design space for “low-risk” SAI strategies, suggesting that solid aerosols could be far less viable than existing models assume.

Paper: Hack, M., McNeill, V. F., Steingart, D., & Wagner, G. (2025). Engineering and logistical concerns add practical limitations to stratospheric aerosol injection strategies. Scientific Reports, 15(1), 34635. https://doi.org/10.1038/s41598-025-20447-2

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