Themed collection Wildfire impacts on atmospheric composition - Topic Highlight

Photochemistry of multifunctional aromatics like vanillin can depend strongly on wavelength, initial concentration, and ionic strength. Using several narrow-band LEDs we present wavelength resolved quantum yields for loss of vanillin.

A universally attachable, lightweight PM_2.5 mobile monitor provides reliable and actionable supplemental information on air quality conditions in communities impacted by wildland fire smoke via a nationwide loan program.

Megafires are increasingly generating Pyrocumulus clouds (PyroCus) through the interplay of atmospheric conditions such as stability and humidity, hot updrafts, and emitted aerosols from burning vegetation.

Rapid production of formic acid in biomass burning smoke is not captured by the Master Chemical Mechanism (MCM) nor simplified GEOS-Chem chemistry, likely due to missing secondary chemical production.

Laser desorption ionisation, coupled with ultrahigh-resolution mass spectrometry, provides an apt reflection of the physical properties of tar balls in wildfire smoke.

A novel instrument designed for crowdsourced data collection on air quality and aerosol optical depth.

Wildfires are significant sources of carbonaceous particles in the atmosphere.

Brown carbon light absorptivity is associated with organic aerosol volatility and elemental carbon concentrations.

The Mt. Bachelor Observatory was frequently impacted by biomass burning smoke in 2021, an extreme forest fire year in the state of Oregon.

Wildfire particulate matter contains high amounts of environmentally persistent free radicals and generates reactive oxygen species with implications for air quality and public health.

Using OH reactivity we assess the major daytime OH radical sinks in western U.S. wildfire plumes and other smoke impacted environments, testing their current model representation while providing a roadmap for future model development.

Wildfires produce furan compounds that are involved in atmospheric oxidant and SOA formation. One such compound, furfural, produces furoyl peroxynitrate (fur-PAN) in the atmosphere, a unique marker for this wildfire chemistry.

Biomass burning and secondary organic aerosols formed by photochemical reactions lead to the highest oxidative potential among urban emission sources and therefore are one of the most hazardous sources in terms of ambient PM toxicity.

Wildfires are a source of primary aerosols and precursors for secondary aerosols to the atmosphere. In this work, we discover that the evolution of these aerosols depends strongly on the coupled effects of dilution, photooxidation, and partitioning.

HYSPLIT modeling analysis. Long-range transport of PM_2.5. Emissions of ammonia and PM_2.5 from biomass burning.

65–74% of light extinction is due to light scattering in Mexico City. Organic aerosols dominate both submicron mass loading and light scattering. Brown carbon and black carbon contribute 22% and 78% to the total light absorption, respectively. Road traffic and regional wildfires are the main contributors to light absorption. The aerosols' optical properties exhibit distinctive diurnal and seasonal patterns.

Representing brown carbon absorption, photobleaching, and secondary organic aerosol formation in wildfire emissions results in improved agreement between WRF-Chem simulations and AERONET observations.

Even though the majority of brown carbon in biomass-burning emissions is soluble in methanol, the methanol-insoluble fraction dominates light absorption at mid-visible wavelengths.

Tropospheric ozone (O₃) negatively impacts human health and is also a greenhouse gas.

Water-soluble BrC in freshly emitted boreal peat combustion particulate matter spans a wide range of molecular sizes, polarities, and light absorption properties; in addition, its largest fraction undergoes solvent-dependent aggregation/dissociation.