Abstract View
Aerosol Properties and Processing during Wintertime under Hazy Condition
SUSAN MATHAI, Zezhen Cheng, Rhenton Brimberry, Nurun Nahar Lata, Swarup China, Pacific Northwest National Laboratory
Abstract Number: 268
Working Group: Urban Aerosols
Abstract
Atmospheric aerosols emitted into the atmosphere often as externally mixed compounds coagulate or condense on each other due to aging to exist in internally mixed state. Variability in mixing state of atmospheric aerosols play a major role in uncertainties associated with the estimated radiative forcing. Meteorological condition plays a major role in determining the mixing state of particles in the atmosphere. We collected samples during wintertime and under hazy condition from a polluted region which is impacted by biomass burning from household activities and agricultural burning. The collected samples were analyzed using multi-modal micro-spectroscopy and chemical imaging techniques such as computer controlled scanning electron microscopy, transmission electron microscopy and scanning transmission X-ray microscopy/near edge X-ray absorption fine structure spectroscopy to determine the size resolved morphology and chemical composition of individual particles. Due to extensive fire activities during winter the K-rich particles are dominant in the atmosphere. We also observed an abundance of sulfates in the sample which could be the result of aqueous phase reaction due to regional haze. Furthermore, we investigated phase state of individual particles with and without inorganic inclusions and our results suggest that particles with inclusions are in semi-solid state while particles without inclusions are in solid-state. The results from this study will help in understanding different mixing state of particles in an urban polluted region and the impact of mixing states on particle phase state.