Dr Simone Tilmes is a Project Scientist III at National Center for Atmospheric Research (NCAR) and the co-chair for the Community Earth System Model (CESM) chemistry-climate working group. Her scientific interests cover the understanding and evaluation of chemical, aerosol and dynamical processes in chemistry-climate models. She has investigated past, present and future evolutions of the ozone hole in both hemispheres based on models and observations. Further research includes interactions in tropospheric chemistry, aerosols, air quality, long-range transport of pollutants, and tropospheric ozone. She is also studying the impact of climate interventions on the Earth’s climate system, the hydrological cycle, sea-ice, and the impact of solar radiation management on dynamics and chemistry in both the troposphere and the stratosphere. Together with a team of scientists, she produced the first stratospheric aerosol geoengineering large ensemble (GLENS) using the Whole Atmosphere Community Climate Model (WACCM), as well as similar simulations with WACCM6, which has been made available to the community in order to investigate the benefits, side effects and risks of stratospheric aerosol interventions.