The Polar AVE website will be undergoing a major upgrade beginning Friday, October 11th at 5:00 PM PDT. The new upgraded site will be available no later than Monday, October 21st. Please plan to complete any critical activities before or after this time.

 

Disclaimer: This material is being kept online for historical purposes. Though accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information, and parts may not function in current web browsers. Visit https://espo.nasa.gov for information about our current projects.

 

Formaldehyde evolution in US wildfire plumes during the Fire Influence on...

Liao, J., G. M. Wolfe, R. A. Hannun, J. M. St. Clair, T. F. Hanisco, J. Gilman, A. Lamplugh, V. Selimovic, G. S. Diskin, J. B. Nowak, H. Halliday, J. P. DiGangi, S. R. Hall, K. Ullmann, C. D. Holmes, C. Fite, A. Agastra, T. B. Ryerson, J. Peischl, I. Bourgeois, C. Warneke, M. Coggon, G. Gkatzelis, K. Sekimoto, A. Fried, D. Richter, P. Weibring, E. Apel, R. S. Hornbrook, S. Brown, C. Womack, M. Robinson, R. Washenfelder, P. Veres, and J. A. Neuman (2022), Formaldehyde evolution in US wildfire plumes during the Fire Influence on Regional to Global Environments and Air Quality experiment (FIREX-AQ), Atmos. Chem. Phys., doi:10.5194/acp-21-18319-2021.
Abstract: 

Formaldehyde (HCHO) is one of the most abundant non-methane volatile organic compounds (VOCs) emitted by fires. HCHO also undergoes chemical production and loss as a fire plume ages, and it can be an important oxidant precursor. In this study, we disentangle the processes controlling HCHO by examining its evolution in wildfire plumes sampled by the NASA DC-8 during the Fire Influence on Regional to Global Environments and Air Quality experiment (FIREX-AQ) field campaign. In 9 of the 12 analyzed plumes, dilution-normalized HCHO increases with physical age (range 1–6 h). The balance of HCHO loss (mainly via photolysis) and production (via OH-initiated VOC oxidation) seems to control the sign and magnitude of this trend. Plume-average OH concentrations, calculated from VOC decays, range from −0.5 (± 0.5) × 106 to 5.3 (± 0.7) × 106 cm−3 . The production and loss rates of dilution-normalized HCHO seem to decrease with plume age. Plume-to-plume variability in dilution-normalized secondary HCHO production correlates with OH abundance rather than normalized OH reactivity, suggesting that OH is the main driver of fire-to-fire variability in HCHO secondary production. Analysis suggests an effective HCHO yield of 0.33 (0.05) per VOC molecule oxidized for the 12 wildfire plumes. This finding can help connect space-based HCHO observations to the oxidizing capacity of the atmosphere and to VOC emissions.

PDF of Publication: 
Download from publisher's website.
Research Program: 
Tropospheric Composition Program (TCP)