Professor V. Faye McNeill Gives Chemical Engineering Colloquium Seminar at Columbia University

On September 24th, Prof. McNeill will be giving a presentation as part of the Chemical Engineering Colloquium at Columbia University.

Below are details and the abstract for Prof. McNeill’s talk.

Atmospheric Aerosols: Chemistry, Clouds, and Climate

825 Mudd Hall, 4-5PM, September 24, 2013.

The chemistry of atmospheric aerosols influences their direct and indirect effects on climate. Inorganic aerosols may acquire an organic component via in situ interactions with volatile organic compounds (VOCs), a family of processes known as secondary organic aerosol (SOA) formation. SOA formation is one of the greatest sources of uncertainty in estimations of aerosol climate forcing. Pathways for aqueous-phase SOA formation have been identified in which water-soluble VOCs dissolve into cloud droplets or wet aerosols, followed by aqueous-phase reactions which lead to the formation of SOA material. Our recent laboratory studies show that particle-phase chemical reactions between organics and inorganic salts can lead to secondary organic products which absorb light in the UV and visible, thus changing the optical properties of the particle.  We have also shown that aqueous-aerosol SOA products may be surface-active, therefore potentially enhancing the ability of small particles to nucleate cloud droplets (CCN activity). In addition to these bulk surfactant effects, our work demonstrates that the surface adsorption of methylglyoxal and acetaldehyde from the gas phase can depress aerosol surface tension and increase CCN activity. Finally, I will introduce a numerical model of coupled gas and aqueous aerosol chemistry that we have developed in order to study the formation of secondary organic aerosol material in aerosol water and the associated changes in aerosol physical properties.