Wednesday, June 8, 2022 - 3:00pm

Abstract:

The net effect of aerosols on the Earth’s climate is highly uncertain. Secondary organic aerosols (SOA) contribute heavily to this uncertainty due to their complex chemical composition. This uncertainty is enhanced by the fact that SOA can be physically and chemically transformed as it slowly disperses through the atmosphere, a process known as aging. Recently, a number of studies have found that condensed-phase photochemical aging of SOA can have a profound effect on its chemical composition and subsequent effects on climate. However, the role of these aging processes in controlling the climate and air pollution is still highly uncertain. Laboratory experiments were conducted to quantify the long term photodegradation rates for a variety of SOA as well as what effects this has on the abundance of glassy SOA in the atmosphere. Results demonstrate a strong case for the critical importance of condensed phase photochemistry in determining climate-relevant properties of organic aerosols.

Speaker: 

Vahe Baboomian

Institution: 

Nizkorodov Group

Location: 

RH 390 and Zoom