Summary: | Wildfires are a common occurrence in many parts of the globe and can emit significant quantities of trace gases and particulate matter, negatively impacting air quality on large spatial scales. Among the various trace gases emitted by wildfires are volatile organic compounds (VOCs). Four VOCs that are of particular importance are methanol (CH3OH), formic acid (HCOOH), peroxyacetyl nitrate (PAN), and ethylene (C2H4). These reactive VOCs can have a variety of negative impacts on the atmospheric chemistry and environment of remote regions including influencing trace gas budgets, impacting atmospheric acidity, and contributing to the ‘Arctic haze’ pollution phenomenon.During August 2017, two independent large-scale wildfires in British Columbia and the Northwest Territories of Canada generated vast smoke plumes that merged and were subsequently transported to the high Arctic. Simultaneous observations by a high-resolution ground-based Fourier transform infrared (FTIR) spectrometer at the Polar Environment Research Laboratory (PEARL) in Eureka, Nunavut (80.05°N, 86.42°W), and the Infrared Atmospheric Sounding Interferometer (IASI) satellite instruments display extreme enhancements in these species relative to background concentrations during the fire-affected period in late August 2017, demonstrating the long-range transport and secondary formation of these typically short-lived species. Comparisons of observations with the GEOS-Chem global chemical transport model illustrate that this exceptional wildfire event contributed to a substantial perturbation to the VOC budget of the high-Arctic atmosphere. info:eu-repo/semantics/nonPublished
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