Evolution of Alternative Stratospheric Aerosol Injection Materials Under Simulated Stratospheric Ageing

Explore a 27-minute lecture by Frank Keutsch examining the chemical and physical properties of alternative solid materials for stratospheric aerosol injection (SAI) beyond traditional sulfate-based options. The presentation delves into crucial laboratory and modeling studies necessary to evaluate these materials' climate and environmental impacts due to the absence of real-world analogues. Learn about advanced research methodologies including scanning near-field optical microscopy (s-SNOM) to analyze individual aerosol particle interactions with radiation, FTIR spectroscopy and UV-visible spectrophotometry to track optical property evolution, and X-ray photoelectron spectroscopy (XPS) to identify chemical changes affecting refractive index variations. The lecture builds upon previous findings regarding ice nucleating properties of alternative SAI materials, providing essential insights for evaluating solid aerosols for potential climate intervention strategies. This Simons Foundation presentation was part of the Solar Radiation Management Annual Meeting 2025.