Researchers primarily rely on two approaches to evaluate and improve climate models that assess the potential risks and efficacy of Stratospheric Aerosol Injection (SAI): comparing outputs across models and drawing lessons from natural analogs, specifically volcanic eruptions like that of Mt. Pinatubo in 1991. While these indirect approaches yield critical insights, both have important limitations. Model intercomparisons are often limited by differences in model structures and assumptions, and natural analogs carry irreducible uncertainties.

In this seminar, Prof. Frank Keutsch will provide an overview of his research on the use of an underutilized approach in SAI research — targeted airborne observations — to gain key insights into processes that govern aerosol formation, transport, atmospheric mixing, and circulation. This research can provide a robust basis for quantifying model uncertainty, illuminating critical knowledge gaps in assessing the risks and efficacy of SAI.

Frank Keutsch is the Stonington Professor of Engineering and Atmospheric Science and Professor of Chemistry and Chemical Biology at Harvard University.