Microphysics of Water in Secondary Organic Aerosol

2019 Faculty Research Award

Award Period: 2019-2021

Ian Bourg, assistant professor of civil and environmental engineering and the Princeton Environmental Institute, aims to characterize the microphysics of water in secondary organic aerosol (SOA) particles, which are nanosized mixtures of water, organic compounds and inorganic ions. Although aerosols such as SOAs have a strong influence on the Earth’s heat budget and on human health, how these tiny droplets form and behave in the atmosphere is poorly understood.

Bourg will use molecular dynamics simulation to model the interactions of SOAs with the atmosphere as the aerosols evolve over time. While molecular dynamics is commonly used in biochemistry and geochemistry, it is sparsely applied to atmospheric chemistry. Bourg’s research has the potential to enhance the representation of the role of atmospheric water in climate and air-quality models, as well as enable more accurate predictions of Earth’s future climate and its effect on human health.


Educational Impact

The project constitutes a new research area for Bourg’s research group, which focuses on the study of water in subsurface environments such as soils and sedimentary rocks. This project will open new collaborations between civil and environmental engineering and Princeton’s Program in Atmospheric and Oceanic Sciences. A significant focus will be on mentoring undergraduate senior thesis students and PEI summer interns, who will be invited to present their research at the annual meeting of the American Chemical Society. The research results will be incorporated into the undergraduate course “Introduction to Environmental Engineering,” which is taught by Bourg. The project also will be used as the basis for project proposals to be submitted to the National Science Foundation and to the Cooperative Institute for Modeling the Earth System (CIMES) operated by Princeton and NOAA’s Geophysical Fluid Dynamics Laboratory located on Princeton’s Forrestal Campus.

Participating Department


Assistant Professor of Civile and Environment Engineering and the Princeton Environmental Institute

Graduate Students 

  •  Xiaohan Li, CEE