AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Detecting Biomass Burning Using Intensive Aerosol Optical Properties in El Paso, Texas - (BC)2 El Paso Field Campaign
SUJAN SHRESTHA, Meghan C. Guagenti, James Flynn, Sergio Alvarez, Sascha Usenko, Rebecca J. Sheesley, Baylor University
Abstract Number: 621 Working Group: Urban Aerosols
Abstract Emissions from anthropogenic sources (e.g. motor vehicle exhaust and coal-fired power plants) have been significantly reduced in the US through the implementation of cleaner technologies, refocusing our efforts to understand the contribution and impact of biomass burning to urban air quality. This is particularly relevant for El Paso where transport of regional biomass burning can drive plumes into the city from across state and international boundaries, resulting in periodic increases in atmospheric pollutants. To study this phenomenon, the Black and Brown Carbon study or (BC)2 El Paso is conducting field measurements from mid-March through September 2019. For (BC)2, the Baylor air quality trailer has been equipped with two tricolour absorption photometers (TAP), a seven-channel aethalometer (AE42), a three-wavelength nephelometer, and carbon monoxide (CO) and nitrogen oxide (NOx) analyzers. This study uses intensive aerosol optical properties: Absorption and Scattering Ångström Exponents (AAE and SAE) and Single Scattering Albedo (SSA) along with BC/CO and CO/NOx ratios to characterize aerosol optical properties in El Paso and to identify biomass burning plumes. SSA, which is the ratio of scattering to total extinction, will determine the net sign of an aerosol’s radiative forcing for El Paso under conditions of routine urban emissions and biomass burning events. The simultaneous operation of the TAP and aethalometer provides an opportunity for inter-comparison. Preliminary results indicate an AAE value near 1, which is indicative of motor vehicle exhaust with little influence from biomass burning plumes with higher AAE. Detailed results from the long-term measurements with supplemental HYSPLIT back trajectory analysis and MODIS fire identification products will be presented during the conference.