Investigating Vertical Profile of Black Carbon Containing Particles and Their Mixing State at the Southern Great Plains

SUSAN MATHAI, Zezhen Cheng, Nurun Nahar Lata, Darielle Dexheimer, Claudio Mazzoleni, Fan Mei, Swarup China, Michigan Technological University

     Abstract Number: 490
     Working Group: Aerosols, Clouds and Climate

Abstract
Black carbon (BC) containing particles affect the climate directly by efficiently absorbing solar radiation and indirectly by serving as cloud and ice nuclei to alter the surface albedo. However, light-absorption properties of BC containing particles are highly variable due to limited understanding in their concentration, physiochemical properties, morphology, and mixing state, leading to large uncertainties in their radiative forcing calculation. In this study, we focus on the the vertical distribution of BC and its mixing states by collecting data at Southern Great Plains (SGP) from during February and April, 2022 by deploying instruments on an Atmospheric Radiation Measurement (ARM) tethered balloon system (TBS). We deployed two micro-aethalometers (AE51 and MA200) to monitor the BC concentration at different altitudes along with the condensation particle counter (CPC) for total particle concentration measurement, and a Portable Optical Particle Spectrometer (POPS, Handix scientific) to monitor the size distribution of the particles. We also investigate the absorption Ångström exponent to investigate the brown carbon. Furthermore, we also deployed Environmental Molecular Science Laboratory’s automated Size and Time-resolved Aerosol Collector (STAC) to collect particles at different altitude. We use multi-modal microscopy and spectroscopy techniques to analyze collected samples and investigate the morphology and mixing state of BC containing particles. This study will improve our understanding of BC particles mixing state, and their variations along vertical column of the atmosphere.