Speaker
Tim Bertram, Ph.D.
Speaker's Institution
University of Wisconsin-Madison
Date
10/13/21
Time
4:00 PM
Location
Virtual Seminar
Additional Information

About the Seminar:

Ocean emissions of dimethyl sulfide (DMS) are a major precursor for the production and growth of aerosol particles, which can act as seeds for the formation of cloud droplets in the marine atmosphere with the subsequent impacts on Earth’s climate. Global aircraft observations indicate that DMS is efficiently oxidized to hydroperoxymethyl thioformate (HPMTF), a previously unrecognized molecule, which necessitates revisiting DMS oxidation chemistry in the marine atmosphere. In this seminar, I will show through ambient observations, laboratory studies, and global modelling that a dominant loss pathway for HPMTF is uptake into cloud droplets. This loss process short circuits gas-phase oxidation and significantly alters the dynamics of aerosol production and growth in the marine atmosphere and the production of long-lived precursors for stratospheric sulfate production.

Photo Credit: Sam Hall (NCAR)

About the Speaker:

Timothy Bertram received a PhD in physical chemistry at the University of California-Berkeley and conducted a NOAA Climate and Global Change post-doctoral fellowship in Atmospheric Science at the University of Washington. He is now a Professor in the Department of Chemistry, Atmospheric and Oceanic Studies, and the Environmental Chemistry and Technology Program at the University of Wisconsin-Madison. His research focuses on field and laboratory measurements of chemical reactions occurring at atmospheric interfaces and the development of novel instrumentation for atmospheric measurement. He is the Associate Director of the NSF Center for Aerosol Impacts on Chemistry of the Environment.

Join Zoom Meeting
https://zoom.us/j/94976316662?pwd=d29UQmpHQ0xtc1M0VTdUbDhldktYZz09

Meeting ID: 949 7631 6662
Passcode: 635287

Join by SIP
94976316662@zoomcrc.com