Date/Time
Date(s) - 18/03/2021
1:30 pm - 2:30 pm

Title:                    Atmosphericchemistry of terpene emissions from pine and sage plants 

Date:                    Thursday, March18, 2021 

Time:                    1:30 p.m.   

Zoom:                  available from sprucel@mcmaster.ca 

Host:                    Dr. Sarah Styler 

Abstract: 

Climatechange is influencing ecosystem health and plant biogeographical distributions.This affects the atmospheric composition and spatiotemporal distribution ofbiogenic volatile organic compounds across the Earth. Perturbations to thetypes of compounds emitted could have significant impacts on secondary organicaerosol (SOA) production, with subsequent effects on atmospheric radiativetransfer and climate. However, the chemistry of many of these compounds(including complex mixtures of these compounds) have not been studied in acontrolled laboratory environment. This presentation will summarize laboratorystudies investigating SOA formation from complex mixtures of real pine and sageemissions. Unexpected effects on aerosol chemistry, composition, and propertiesattributed to the presence of oxygenated monoterpenes and acyclic terpenes inthe mixture were observed. Oxygenated monoterpenes (i.e. camphor andeucalyptol) that dominate emissions from sage and sagebrush produce SOA with morehighly oxygenated molecules than SOA formed from more traditionally-studiedterpenes. Acyclic terpenes (i.e. ?-myrcene and ?-farnesene) thatare often associated with plant stress, reduce SOA yields and promotefragmentation reactions while increasing the viscosity of the resulting SOA.Aerosol chemistry of these compounds could become increasingly important withthe expansion of drought-tolerant sage scrub and more frequent occurrence ofplant stress conditions.