Debra Weisenstein is a senior researcher in the Harvard John A. Paulson School of Engineering and Applied Sciences. Her work focuses on modeling stratospheric chemistry and aerosol microphysics with application to solar geoengineering. She developed the AER 2-D chemisry-transport-aerosol model which has been applied to studies of atmospheric sulfur, volcanic eruptions, and aircraft impacts on the atmosphere, as well as to geoengineering by injection of SO2 and H2SO4. Recent work focuses on modeling solid particles with fractal structure for possible geoengineering application. She collaborates with Prof. Thomas Peter at ETH in Zurich and was a lead author of the SPARC Assessment of Stratospheric Aerosol Properties report, published in 2006 by the World Climate Research Program.