Implementation and impacts of surface and blowing snow sources of Arctic bromine activation within WRF‐Chem 4.1.1

• Published in: Journal of Advances in Modeling Earth Systems
• Main Authors: Marelle, Louis, Thomas, Jennie, Ahmed, Shaddy, Tuite, Katie, Stutz, Jochen, Dommergue, Aurélien, Simpson, William, Frey, Markus, Baladima, Foteini
• Other Authors: Institut des Géosciences de l’Environnement (IGE), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Atmospheric and Oceanic Sciences Los Angeles (AOS), University of California Los Angeles (UCLA), University of California-University of California, Geophysical Institute Fairbanks, University of Alaska Fairbanks (UAF), British Antarctic Survey (BAS), Natural Environment Research Council (NERC), This work also supported by the CNRS INSU LEFE-CHAT program under the grant Brom-Arc. We acknowledge support for William R. Simpson from the National Science Foundation grant ARC-1602716. This work was performed using HPC resources from GENCI-IDRIS (Grant A007017141) and the IPSL mesoscale computing center (CICLAD: Calcul Intensif pour le CLi-mat, l'Atmosphère et la Dynamique). We thank the WRF-Chem development and support teams at NOAA, NCAR, and PNNL for their support and collaborations. We acknowledge NCAR ACOM for providing the WRF-Chem chemical boundary conditions used in this study. We acknowledge use of the WRF-Chem pre-processor tools provid-ed by the Atmospheric Chemistry Ob-servations and Modeling Lab (ACOM) of NCAR. We acknowledge the NOAA Global Monitoring Laboratory Earth System Research Laboratories and the O-Buoy program for providing obser-vations used in this study.
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; Arctic; Sea ice
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-03266425; https://hal-insu.archives-ouvertes.fr/insu-03266425v2/document; https://hal-insu.archives-ouvertes.fr/insu-03266425v2/file/2020MS002391-1.pdf; https://doi.org/10.1029/2020ms002391

International audience Elevated concentrations of atmospheric bromine are known to cause ozone depletion in the Arctic, which is most frequently observed during springtime. We implement a detailed description of bromine and chlorine chemistry within the WRF-Chem 4.1.1 model, and two different descriptions of Arctic bromine activation: (1) heterogeneous chemistry on surface snow on sea ice, triggered by ozone deposition to snow (Toyota et al., 2011), and (2) heterogeneous reactions on sea salt aerosols emitted through the sublimation of lofted blowing snow (Yang et al., 2008). In both mechanisms, bromine activation is sustained by heterogeneous reactions on aerosols and surface snow. Simulations for spring 2012 covering the entire Arctic reproduce frequent and widespread ozone depletion events, and comparisons with observations of ozone show that these developments significantly improve model predictions during the Arctic spring. Simulations show that ozone depletion events can be initiated by both surface snow on sea ice, or by aerosols that originate from blowing snow. On a regional scale, in spring 2012, snow on sea ice dominates halogen activation and ozone depletion at the surface. During this period, blowing snow is a major source of Arctic sea salt aerosols but only triggers a few depletion events.