Formation and Evolution of VOCs, Black Carbon, and SOA in Wildfire Plumes

Hongyu Qin

doi:10.54097/b2mmd794

Authors

Hongyu Qin

DOI:

https://doi.org/10.54097/b2mmd794

Keywords:

Volatile Organic Compounds; Black Carbon; Secondary Organic Aerosol; Wildfire Emissions.

Abstract

Wildfires are major sources of atmospheric gases and particles that influence air quality, radiative forcing, and human health on local to global scales. This review synthesizes laboratory, field, and modeling evidence on the formation of volatile organic compounds (VOCs) and black carbon (BC) during combustion and the subsequent evolution of these emissions into secondary organic aerosol (SOA). Combustion regime and fuel composition govern VOC speciation and BC yields; multipathway oxidation (OH, O₃, NO₃, and aqueous processes) produces SOA within hours to days; and vertical transport, including pyrocumulonimbus lofting, can extend particle lifetimes to months, enhancing their climatic relevance. Heterogeneous BC–SOA mixing states modulate optical properties, hygroscopicity, and atmospheric aging, thereby shaping radiative impacts and long-range transport. This research highlights key uncertainties in S/IVOC emissions, nighttime and aqueous chemistry, BC coating heterogeneity, and stratospheric smoke persistence, and outlines priorities for improving air-quality forecasts, climate projections, and health-risk assessments in the context of a warming world where wildfire frequency is expected to rise.

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