Year: 2024
Type: article
Abstract: The Alaskan Layered Pollution and Chemical Analysis (ALPACA) field campaign included deployment of a suite of atmospheric measurements in January–February 2022 with the goal of better understanding atmospheric processes and pollution under cold and dark conditions in Fairbanks, Alaska. We report on measurements of particle composition, particle size, ice nucleating particle (INP) composition, and INP size during an ice fog period (29 January–3 February). During this period, coarse particulate matter (PM10) concentrations increased by 150% in association with a decrease in air temperature, a stronger temperature inversion, and relatively stagnant conditions. Results also show a 18%–78% decrease in INPs during the ice fog period, indicating that particles had activated into the ice fog via nucleation. Peroxide and heat treatments performed on INPs indicated that, on average, the largest contributions to the INP population were heat‐labile (potentially biological, 63%), organic (31%), then inorganic (likely dust, 6%). Measurements of levoglucosan and bulk and single‐particle composition corroborate the presence of dust and aerosols from combustion sources. Heat‐labile and organic INPs decreased during the peak period of the ice fog, indicating those were preferentially activated, while inorganic INPs increased, suggesting they remained as interstitial INPs. In general, INP concentrations were unexpectedly high in Fairbanks compared to other locations in the Arctic during winter. The fact that these INPs likely facilitated ice fog formation in Fairbanks has implications for other high latitude locations subject to the hazards associated with ice fog.
DOI: 10.1029/2024jd041170
Authors: Emily Lill, Emily J. Costa, Kevin Barry, Jessica A. Mirrielees, Monica Mashkevich, Judy Wu, Andrew L. Holen, Meeta Cesler‐Maloney, Paul J. DeMott, Russell Perkins, Thomas Hill, Amy Sullivan, Ezra Levin, William R. Simpson, Jingqiu Mao, Brice Temime‐Roussel, Barbara D'Anna, Kathy S. Law, Andrew P. Ault, Carl Schmitt, Kerri A. Pratt, Emily V. Fischer, Jessie Creamean
Institutions: Colorado State University, University of Michigan, University of Alaska Fairbanks, Handix Scientific (United States), Centre National de la Recherche Scientifique, Aix-Marseille Université, Université de Versailles Saint-Quentin-en-Yvelines, Sorbonne Université, Institut Pierre-Simon Laplace, Laboratoire atmosphères, milieux, observations spatiales
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: hybrid
Estimated APC paid: $3,880
Funders: National Science Foundation, U.S. Department of Energy, University of Michigan, Environmental Molecular Sciences Laboratory, Agence Nationale de la Recherche, Centre National de la Recherche Scientifique, Institut Polaire Français Paul Emile Victor, Horace H. Rackham School of Graduate Studies, University of Michigan, Biological and Environmental Research, Pacific Northwest National Laboratory
Awards: Climate-relevant aerosol sources and processes in the Arctic, G4300016217, Collaborative Research: NNA Track 1: Sustainably Navigating Arctic Pollution Through Engaging Communities (SNAP-TEC), Collaborative Research: A Comprehensive Evaluation of the Interactions between Pollution and Hazardous Ice Fog in Interior Alaska, Collaborative Research: A Comprehensive Evaluation of the Interactions between Pollution and Hazardous Ice Fog in Interior Alaska
OpenAlex ID: W4401816828