October 22, 2018

One of three San Antonio field sites where Wood’s ECHAMP instrument was deployed.

In May of 2017, Ezra Wood, PhD, associate professor of chemistry, and a group of researchers deployed a large suite of analytical instrumentation to several sites in and near San Antonio, Texas. Their goal was to investigate the formation of ozone, also known as photochemical smog. Now, Wood and his College of Engineering colleague Shannon Capps, PhD, have received a $130,000 grant from the Texas Commission on Environmental Quality's Air Quality Research Program (TECQ-AQRP) to analyze the data and continue their investigation of San Antonio’s air quality.

Photochemical smog, also known as “Los Angeles smog,” occurs when peroxy radicals react with nitric oxide, emitted by combustion such as in automobiles, in the presence of sunlight. Wood, along with Jessica Pavelec, BS chemistry ’18, and Daniel Anderson, PhD, postdoctoral chemistry fellow, traveled to San Antonio to measure the highly toxic gas ozone, which causes respiratory problems, plant damage and more. With them was Wood’s "ECHAMP" (Ethane CHemical AMPlifier) instrument, which quantifies concentrations of peroxy radicals — the key precursor to ozone formation.

With the support of the grant, the researchers will analyze the field data to investigate if current models correctly capture the pollutant emission levels. Using computer models of air quality, the team will simulate the smog formation process across San Antonio. Their overall goal is to elucidate the mechanisms of photochemical smog formation in San Antonio to inform mitigation strategies.

“San Antonio is facing a situation common to many cities: their air pollution is caused by emission sources both within San Antonio and upwind,” Wood says. “Our research should be able to quantify the importance of upwind sources compared to urban sources. We'll be focusing on ozone, which is not emitted directly, but formed as nitrogen oxides and volatile organic compounds ‘cook’ in the sunlight.”

He adds that, compared to San Antonio, Philadelphia’s air quality is worse!

Visit the Wood Group Website to learn more