The Abundance and Sources of Ice Nucleating Particles Within Alaskan Ice Fog

• Published in: Journal of Geophysical Research: Atmospheres
• Main Authors: Lill, Emily, Costa, Emily, J, Barry, Kevin, Mirrielees, Jessica, A, Mashkevich, Monica, Wu, Judy, Holen, Andrew, L, Cesler‐maloney, Meeta, Demott, Paul, J, Perkins, Russell, Hill, Thomas, Sullivan, Amy, Levin, Ezra, Simpson, William, R, Mao, Jingqiu, Temime‐roussel, Brice, d'Anna, Barbara, Law, Kathy S., Ault, Andrew, P, Schmitt, Carl, Pratt, Kerri, A, Fischer, Emily, V, Creamean, Jessie
• Other Authors: Department of Atmospheric Science Fort Collins, Colorado State University Fort Collins (CSU), Department of Chemistry Ann Arbor, University of Michigan Ann Arbor, University of Michigan System-University of Michigan System, Department of Chemistry and Biochemistry Fairbanks, University of Alaska Fairbanks (UAF), Geophysical Institute Fairbanks, Handix Scientific Inc., Laboratoire Chimie de l'environnement (LCE), Aix Marseille Université (AMU)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Alaska Climate Research Center (ACRC), Department of Earth and Environmental Sciences Ann Arbor, ANR-21-CE01-0017,CASPA,Sources d'aérosols et processus liés au climat dans l'Arctique(2021)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2024
• Subjects: [SDE]Environmental Sciences; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; Arctic; Fairbanks; Alaska
• Online Access: https://insu.hal.science/insu-04676894; https://insu.hal.science/insu-04676894/document; https://insu.hal.science/insu-04676894/file/JGR%20Atmospheres%20-%202024%20-%20Lill%20-%20The%20Abundance%20and%20Sources%20of%20Ice%20Nucleating%20Particles%20Within%20Alaskan%20Ice%20Fog.pdf; https://doi.org/10.1029/2024jd041170

International audience 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 (PM 10 ) 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.