Seminar 9/28/2011 - Prof. V. Faye McNeill, Columbia University: Atmospheric Aerosols: Chemistry, Clouds, and Climate
Abstract: The chemistry of atmospheric aerosols influences their direct and indirect effects on climate. I will present results of our recent laboratory studies showing 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. I will introduce a 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 aerosol optical properties. We have also studied the sources and properties of surface-active organic species in aerosols. Organic films at the gas-aerosol interface can reduce aerosol surface tension, potentially enhancing the ability of small particles to nucleate cloud droplets (CCN activity). Our work has shown that uptake of methylglyoxal, acetaldehyde, and formaldehyde from the gas phase driven by aqueous-phase oligomerization chemistry is a potentially significant source of surface-active organic material in aerosols. Aerosol chamber studies of the CCN activity of particles exposed to gas-phase surfactants will be presented.
Bio: V. Faye McNeill has been an assistant professor in the Department of Chemical Engineering at Columbia University since 2007. She received her B.S. in Ch.E. from Caltech in 1999 and in 2005 she received her PhD in Ch.E. from MIT, where she was a NASA Earth System Science Fellow. From 2005-2007 she was a postdoctoral scholar at the University of Washington Department of Atmospheric Sciences. She received the NSF CAREER and the ACS Petroleum Research Fund Doctoral New Investigator awards in 2009. She is an Editor for Atmospheric Chemistry and Physics and is a Director of AAAR and the AIChE Environmental Division.
All seminars are held on Wednesdays from 12:00 noon-1:00 p.m. in the Bowen Hall Auditorium Room 222. A light lunch is provided at 11:30 a.m. in the Bowen Hall Atrium immediately prior to the seminar.
Location: Bowen Hall Atrium
Date/Time: 09/28/11 at 12:00 pm - 09/28/11 at 1:00 pm
Category: PRISM/PCCM Seminar Series