Wednesday, July 24, 2019
3:00 – 4:00 PM
200 College Street, WB 407
New perspectives on sources of reactive gas-phase organic compounds & the chemical complexity of secondary organic aerosol
DREW R. GENTNER
CHEMICAL & ENVIRONMENTAL ENGINEERING
Abstract: Gas-phase organic compounds (including volatile organic compounds; VOCs) are key precursors to secondary organic aerosol (SOA) and tropospheric ozone. Through several bottom-up approaches, we evaluate the evolving role of non-combustion-related emissions in urban air quality, and demonstrate that non-combustion-related sources now contribute a major, but poorly-characterized fraction of SOA and ozone precursors from anthropogenic sources. We present an expanded framework for classifying volatile, intermediate, and semi-volatile emissions from this diverse array of sources that emphasizes a life cycle approach over longer timescales and multiple separate emission pathways. We also perform an extensive untargeted molecular-level intercomparison of SOA from three diverse field sites and an environmental chamber. Despite similar bulk composition, we report large molecular-level variability between multi-hour organic aerosol samples at each site, with 66% of compounds differing between consecutive samples. Through observations and model results, we evaluate the roles of emissions, chemical age, and oxidation conditions in driving this variability, and its potential implications.
If you are unable to join the meeting in person, please join this meeting from your computer, tablet or smartphone. https://global.gotomeeting.com/join/607383413
You can also dial in using your phone. For supported devices, tap a one-touch number below to join instantly.
Canada: +1 (647) 497-9391
- One-touch: tel:+16474979391,,607383413#
Access Code: 607-383-413
New to GoToMeeting? Get the app now and be ready when your first meeting starts: https://global.gotomeeting.com/install/607383413