EES Air Pollution Seminar: Predicting aerosol effects on weather and climate at high spatial resolution

Details

Hamish Gordon, Ph.D., Assistant Professor, Department of Chemical Engineering, Carnegie Mellon University

Abstract: Aerosol-cloud interactions are a key source of uncertainty in accurately simulating how Earth’s radiative balance is affected by human activities. Clouds are very variable on small spatial scales, so simulations of weather and climate require high spatial resolution to represent them. In this seminar I will discuss how we have developed and applied the weather and climate model of the UK Met Office to represent aerosol-cloud interactions at high spatial resolution. I will focus on two example scientific questions my group is addressing, or helping to address. First, I will discuss how aerosol formation via gas-to-particle conversion, or nucleation of new aerosols, contributes to concentrations of the aerosols that form cloud droplets, and how clouds in turn create favorable environments for this process to occur. In this context I will explain our understanding of how, quantitatively, aerosol formation is important to aerosol radiative forcing of climate. Second, I will discuss how we can use the model to better predict aerosol effects on the visibility and lifecycle of fog, which is of use in numerical weather prediction. Our studies of fog motivate a more detailed examination of how weather and climate models can simulate the process by which aerosols activate to form cloud droplets.

Bio: Hamish Gordon is an assistant professor in chemical engineering and a member of CMU’s Center for Atmospheric Particle Studies. His research interests are focused on the effects of air pollution and natural airborne particles on clouds and climate. He received his first degree from the University of Cambridge in 2009, and his doctorate from the University of Oxford in experimental high energy physics in 2013. After a Marie-Curie postdoctoral fellowship at CERN in Geneva from 2013 to 2016, and a second postdoc at the University of Leeds in the UK from 2016 to 2019, he moved to Carnegie Mellon, first as assistant research professor and then as assistant professor since 2022.