New Jersey Institute of Technology researchers received a $620,000 grant from the National Science Foundation to advance understanding of the way in which soot particles from combustion of fossil fuels are driving climate change in the Earth’s atmosphere.
Associate professor of chemistry Alexei Khalizov and associate professor of chemical and materials engineering Gennady Gor will lead the project, “A Multiscale Model for Restructuring of Atmospheric Soot Particles.”
Researchers say the new three-year project aims to improve ways of describing soot nanoparticles in atmospheric models, while advancing atmospheric scientists’ fundamental understanding of the complex microphysics that govern how soot particles travel and change their composition in the atmosphere.
The results could also aid policymakers in developing more effective control strategies for soot pollution in the future.
“Soot is a potent climate-forcing agent with a warming contribution as much as one-third of that from carbon dioxide, yet, there is still much uncertainty over exactly what impact these particles are having in our atmosphere compared to carbon dioxide,” Khalizov said. “Our project will help reduce this uncertainty by improving the ability of models to describe the evolution of these particles in the atmosphere and produce more accurate predictions of climate warming caused by soot.”
Soot nanoparticles are typically released through combustion, produced by burning fuels or during forest fires, for example. Once in the atmosphere, they absorb solar light, converting it into heat and warming the air.
The particles also engage in condensation-evaporation cycles with trace gas chemicals and water vapor.
Khalizov and Gor say that through this process, the transport and optical properties of the particles can be drastically altered — in turn, changing their impact on air quality and climate in a way that can be hard to predict using existing modeling approaches.
“Soot particles have complex lacy structure and can be best described as fractal aggregates of graphitic spherules. … But, in the atmosphere, these aggregates collapse into compact globules, altering the optical and gas transport properties of soot,” explained Gor. “Existing models cannot capture such changes because they represent these complex particles in a highly simplified way, most often as single spheres.”
The team is now developing a new model that explicitly considers the complex morphology of soot particles in the atmospheric environment, with the scope of the project spanning atomic-level simulations of gas-surface interactions and advanced microscopy, performed at NJIT’s Otto H. York Center for Environmental Engineering and Science and Brookhaven National Lab’s Center for Functional Nanomaterials.
Once developed, the research will be incorporated into a larger atmospheric model at University of Illinois–Urbana Champaign, called PartMC-MOSAIC, through collaboration with UIUC atmospheric sciences professor Nicole Riemer.
The project was initiated with support from the NJIT Faculty SEED award and builds on research themes from Khalizov’s previous NSF project, “Kinetics and Mechanism of Restructuring of Atmospheric Soot and Associated Impact on Light Absorption.”
Through the course of the grant, the project will also provide interdisciplinary training for a postdoctoral researcher, as well as offer cutting-edge research experience for graduate, undergraduate and high school students, including students from low-income families (via the ACS SEED program).
