Sources and Processes Influencing Local Arctic Wintertime Air Pollution

• Main Authors: Law, Kathy S., Brett, Natalie, Raut, Jean-Christophe, Onishi, Tatsuo, Ravetta, François, Dieudonné, Elsa, Barret, Brice, Fochesatto, Gilberto Javier, Arnold, Steven, Temime-Roussel, Brice, d'Anna, B., Albertin, Sarah, Cesler‐maloney, Meeta, Simpson, William, R., Mao, Jingqiu, Roberts, Tjarda, J, Pohorsky, Roman, Baccarini, Andrea, Schmale, Julia, Decesari, Stefano, Donateo, Antonio, Pappaccogli, Gianluca, Scoto, Federico, Gilliam, Robert, Fahey, Kathleen
• Other Authors: 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), Laboratoire de Physico-Chimie de l'Atmosphère (LPCA), Université du Littoral Côte d'Opale (ULCO), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS), University of Alaska Fairbanks (UAF), University of Leeds, Laboratoire Chimie de l'environnement (LCE), Aix Marseille Université (AMU)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry and Biochemistry Fairbanks, Geophysical Institute Fairbanks, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales Paris (CNES), Ecole Polytechnique Fédérale de Lausanne (EPFL), CNR Institute of Atmospheric Sciences and Climate (ISAC), National Research Council of Italy, US Environmental Protection Agency (EPA)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDE]Environmental Sciences; Arctic; Alaska
• Online Access: https://insu.hal.science/insu-03914926

International audience Wintertime Arctic air pollution is influenced by long-range transport of remote sources and local within-Arctic sources contributing to the build up of Arctic haze. Local emissions and resulting ground-level pollutant abundances are enhanced during cold winters especially during cold stable episodes with strong surface temperature inversions and light winds that limit pollutant dispersion, and lead to air quality exceedances. Fairbanks in Interior Alaska is a city with episodes of severe wintertime pollution. However, there are many uncertainties in our understanding about pollution sources and secondary aerosol formation under cold, dark winter conditions, when photochemistry is limited. The role of meteorological processes in the Arctic boundary layer is also poorly understood and often difficult to model.These issues were comprehensively examined through the collection of datasets on atmospheric composition and meteorology during the international ALPACA (Alaskan Layered Pollution and Chemical Analysis) field campaign in January and February 2022 in Fairbanks. One goal is to understand how meteorological processes influence surface, and vertical distributions, of aerosols and trace gases. Here, we analyze a combination of measurements collected at sites experiencing different pollution levels, including surface aerosol composition, trace gas profiles collected on a tethered balloon (EPFL helikite), wind lidar and other meteorological measurements. An overview of the different measurements will be presented as a function of meteorological conditions, in particular atmospheric stability. Particular episodes will be highlighted showing evidence for vertical exchange (turbulence) or possible influence from elevated power plant stack emissions. Particle dispersion modelling is used to examine emission sources contributing to surface pollution episodes and elevated plumes. The regional extent of pollution from the Fairbanks area will also be considered and compared to pollutant levels in ...