The Sensitivity of Modeled Secondary Organic Aerosol (SOA) Formation to Differences in Speciation Profiles of Biomass Burning Derived Non-Methane Organic Gases (NMOGs)

SAMIHA BINTE SHAHID, William P. L. Carter, Robert J. Yokelson, Kelley Barsanti, University of California, Riverside

     Abstract Number: 572
     Working Group: Aerosol Chemistry

Abstract
Biomass burning (BB) is a major contributor of non-methane organic gases (NMOGs) in the atmosphere. These highly reactive compounds can have significant impacts on tropospheric chemistry by influencing oxidant concentrations and formation of secondary pollutants, including secondary organic aerosol (SOA). Recent field and laboratory campaigns have made significant progress in measuring the emissions of ~1000s of NMOGs from BB. However, these measurements have not yet been fully integrated into models, which typically include representation of only a limited subset of measured NMOGs. To facilitate the use of recent BB emissions data in models, we developed the Next-generation Emissions InVentory expansion of Akagi (NEIVA). NEIVA is a comprehensive emission factor database that integrates data from laboratory- and field-based biomass burning studies that have been published since 2015 with data from the widely used Akagi et al. 2011 compilation. NEIVA provides detailed speciation of NMOGs emitted from BB grouped into 14 globally relevant fuel or fire types, and uses this information to generate NMOG profiles for gas-phase mechanisms including SAPRC, MOZART, and GEOS-Chem. This allows for the translation of chemically-detailed measurements into model-ready inputs. To evaluate the sensitivity of BB plume chemistry and composition to NMOG speciation, model simulations were performed using NEIVA and two other existing BB inventories as inputs, Andreae 2019 and EPA SPECIATE. Modeling was performed using the Lagrangian plume model case in F0AM, with an integrated thermodynamic equilibrium SOA model we developed based on the CMAQ AERO-07 aerosol module. The model outputs used for comparison included OH reactivity, gas-phase product mixing ratios, and SOA mass concentrations. The model simulations demonstrate the sensitivity of plume chemistry and composition to NMOG speciation and support the need to more adequately represent the diversity of NMOGs emitted from BB.