Visible Light Absorption by Alumina Aerosols

This 20-minute talk by Rajan Chakrabarty explores the critical research on visible light absorption properties of alumina aerosols for stratospheric aerosol injection (SAI) applications. Discover the progress made in the first year of research investigating alumina (Al2O3) particles, which are both proposed candidates for SAI and emitted during spacecraft reentry. Learn about the development of state-of-the-art photoacoustic spectrometers for in-situ aerosol light absorption measurements, research on particle absorption cross-sections and complex refractive indices using advanced techniques like electron energy-loss spectroscopy (EELS), and findings from molecular-scale density functional theory calculations of different alumina polymorphs. Understand why establishing accurate absorption properties across the near-ultraviolet-visible-infrared wavelength range is essential for estimating climate impacts, especially as spacecraft emissions are expected to increase in coming years.