Dr. Hannah S. Kenagy

Hannah S. Kenagy
Department of Civil & Environmental Engineering
Massachusetts Institute of Technology
Abstract

Impacts of peroxy radical chemistry on atmospheric organic aerosol production

Atmospheric aerosol particles impact climate by altering the Earth’s radiative balance and can be detrimental to human health when inhaled. Organic aerosol constitutes a large, and often dominant, fraction of the tropospheric aerosol mass, and much of that organic aerosol is secondary, produced from volatile organic compounds (VOCs) that are sufficiently oxidized in the atmosphere to be condensable. The amount and properties of secondary organic aerosol (SOA), which ultimately govern its air quality and climate impacts, are controlled by the complex kinetics, product distributions, and branching ratios along reaction pathways of organic oxidation. Here, I focus on a key branching point in the oxidation of VOCs that controls the production of SOA, namely the fate of organic peroxy radicals (RO2). First, I will discuss the contribution of organic nitrates (RONO2), a product of the reaction between RO2 and NO radicals, to urban organic aerosol using airborne field measurements over the Korean Peninsula in conjunction with simulations from an atmospheric chemical transport model. Second, I will describe new methods for model-informed experimental design that allow laboratory experiments of SOA production to access atmospheric distributions of RO2 fate for the first time.

Hannah S. Kenagy

Dr. Hannah S. Kenagy (she/her) is an atmospheric chemist currently working as an NSF Postdoctoral Fellow in the Department of Civil and Environmental Engineering at MIT. Kenagy first became interested in atmospheric chemistry during her undergraduate work at the University of Chicago and the University of Edinburgh before completing a PhD in Chemistry as an NSF Graduate Research Fellow at UC Berkeley. Kenagy’s research utilizes an integrated combination of measurement and modeling techniques to better understand chemical pathways in the atmosphere that contribute to the atmospheric oxidation capacity and the production and fate of air pollutants globally. Kenagy’s PhD work used a combination of airborne field measurements and modeling to better understand the urban chemistry of nitrogen oxides, pollutants emitted during combustion which impact the production of ozone and aerosol particles. In her postdoctoral work, Kenagy is integrating modeling and laboratory studies to disentangle the effects of multigeneration oxidation on the formation of atmospheric organic aerosols. Kenagy also enjoys mentoring students and fostering in them an excitement for atmospheric chemistry, as well as doing outreach to make science accessible to all.

Hosted by Professor Michael Bowser