This is a past event.

Matt Alvarado
Atmospheric and Environmental Research, Inc.

Biomass burning is a major source of atmospheric trace gases and particles that impact air quality and climate at urban, regional, and global scales. Within minutes after emission, rapid, complex photochemistry within a smoke plume can cause large changes in smoke composition. In some plumes, this can lead to significant increases in the concentrations of ozone and aerosols after less than an hour of aging, while in other, generally boreal, plumes only small changes are observed. Being able to understand and simulate this rapid chemical evolution under a wide variety of conditions is thus a critical part of forecasting the impact of these fires on urban and regional air quality. In this talk, I will discuss how aircraft and satellite observations, when combined with state-of-the-art chemical transport models such as the Aerosol Simulation Program (ASP), can be used to evaluate the ozone and aerosol formation within smoke plumes. Focusing on biomass burning plumes recently sampled over California and the Yucatan, we will examine several potential explanations for the high levels of OH and ozone observed within these smoke plumes, such as (1) the photolysis of HONO emitted directly by the fires, (2) the secondary formation of HONO from NOx via heterogeneous chemistry within the smoke plume, and (3) the recycling of OH during the oxidation of some organic gases within the smoke plumes, as has been observed for isoprene.

Host Louisa Kramer