Modelling Arctic halogen chemistry and its impacts on ozone and mercury
Halogens are an important component of Arctic atmospheric chemistry, responsible for the depletion of boundary layer ozone and mercury, oxidation of hydrocarbons, and impacts on nitrogen oxide chemistry and oxidative capacity. During spring, reactive halogens are photochemically activated on salty s...
Main Author: | |
---|---|
Other Authors: | , , , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | French |
Published: |
HAL CCSD
2022
|
Subjects: | |
Online Access: | https://theses.hal.science/tel-04368946 https://theses.hal.science/tel-04368946/document https://theses.hal.science/tel-04368946/file/AHMED_2022_archivage.pdf |
id |
ftinsu:oai:HAL:tel-04368946v1 |
---|---|
record_format |
openpolar |
spelling |
ftinsu:oai:HAL:tel-04368946v1 2024-04-21T07:56:18+00:00 Modelling Arctic halogen chemistry and its impacts on ozone and mercury Modélisation de la chimie arctique des halogènes et de ses impacts sur l'ozone et le mercure Ahmed, Shaddy Institut des Géosciences de l’Environnement (IGE) Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ) Université Grenoble Alpes (UGA) Université Grenoble Alpes 2020-. Aurélien Dommergue Jennie L. Thomas 2022-12-02 https://theses.hal.science/tel-04368946 https://theses.hal.science/tel-04368946/document https://theses.hal.science/tel-04368946/file/AHMED_2022_archivage.pdf fr fre HAL CCSD NNT: 2022GRALU030 tel-04368946 https://theses.hal.science/tel-04368946 https://theses.hal.science/tel-04368946/document https://theses.hal.science/tel-04368946/file/AHMED_2022_archivage.pdf info:eu-repo/semantics/OpenAccess https://theses.hal.science/tel-04368946 Sciences de la Terre. Université Grenoble Alpes [2020-.], 2022. Français. ⟨NNT : 2022GRALU030⟩ Modelling Halogens Arctic Atmospheric chemistry Ozone Mercury Modélisation Arctique Halogènes Chimie atmosphérique Mercure [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/doctoralThesis Theses 2022 ftinsu 2024-04-05T00:27:42Z Halogens are an important component of Arctic atmospheric chemistry, responsible for the depletion of boundary layer ozone and mercury, oxidation of hydrocarbons, and impacts on nitrogen oxide chemistry and oxidative capacity. During spring, reactive halogens are photochemically activated on salty surfaces (e.g. land-based snow, snow on sea ice, aerosols) and released into the atmosphere. However, the interplay between polar chemical emissions, recycling, transport, and chemistry is complex and remains poorly understood. As a result, descriptions of such processes in atmospheric chemistry models are largely simplified or neglected. This thesis presents an investigation of the role of halogens (chlorine and bromine) on springtime Arctic boundary layer chemistry, through the development and use of atmospheric chemistry models.First, a 1-dimensional model (PACT-1D) is used to study molecular halogen emissions from surface snow and the impact on oxidative chemistry within the boundary layer. The model is used to simulate reactive halogen chemistry observed during the spring 2009 OASIS (Ocean-Atmospheric-Sea ice-Snowpack) measurement campaign in Utqiagvik, Alaska. Model results show that chlorine can be confined to a very shallow layer near the surface, resulting in a large chemical reactivity gradient with altitude. Second, the 3-dimensional WRF-Chem model is used to investigate the interaction of halogens with ozone and mercury during Arctic spring. Several major WRF-Chem model developments are made in this work, including the addition of a new mercury chemical description. The model is evaluated with unique data from the central Arctic, obtained during the 2020 MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) expedition. Model results show that bromine emissions and recycling from surface snow and sea ice are necessary to capture ozone and mercury depletion events. This work highlights a need for improved model descriptions of surface emissions to accurately represent boundary layer ... Doctoral or Postdoctoral Thesis Arctique* Sea ice Alaska Institut national des sciences de l'Univers: HAL-INSU |
institution |
Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
French |
topic |
Modelling Halogens Arctic Atmospheric chemistry Ozone Mercury Modélisation Arctique Halogènes Chimie atmosphérique Mercure [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
Modelling Halogens Arctic Atmospheric chemistry Ozone Mercury Modélisation Arctique Halogènes Chimie atmosphérique Mercure [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Ahmed, Shaddy Modelling Arctic halogen chemistry and its impacts on ozone and mercury |
topic_facet |
Modelling Halogens Arctic Atmospheric chemistry Ozone Mercury Modélisation Arctique Halogènes Chimie atmosphérique Mercure [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
Halogens are an important component of Arctic atmospheric chemistry, responsible for the depletion of boundary layer ozone and mercury, oxidation of hydrocarbons, and impacts on nitrogen oxide chemistry and oxidative capacity. During spring, reactive halogens are photochemically activated on salty surfaces (e.g. land-based snow, snow on sea ice, aerosols) and released into the atmosphere. However, the interplay between polar chemical emissions, recycling, transport, and chemistry is complex and remains poorly understood. As a result, descriptions of such processes in atmospheric chemistry models are largely simplified or neglected. This thesis presents an investigation of the role of halogens (chlorine and bromine) on springtime Arctic boundary layer chemistry, through the development and use of atmospheric chemistry models.First, a 1-dimensional model (PACT-1D) is used to study molecular halogen emissions from surface snow and the impact on oxidative chemistry within the boundary layer. The model is used to simulate reactive halogen chemistry observed during the spring 2009 OASIS (Ocean-Atmospheric-Sea ice-Snowpack) measurement campaign in Utqiagvik, Alaska. Model results show that chlorine can be confined to a very shallow layer near the surface, resulting in a large chemical reactivity gradient with altitude. Second, the 3-dimensional WRF-Chem model is used to investigate the interaction of halogens with ozone and mercury during Arctic spring. Several major WRF-Chem model developments are made in this work, including the addition of a new mercury chemical description. The model is evaluated with unique data from the central Arctic, obtained during the 2020 MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) expedition. Model results show that bromine emissions and recycling from surface snow and sea ice are necessary to capture ozone and mercury depletion events. This work highlights a need for improved model descriptions of surface emissions to accurately represent boundary layer ... |
author2 |
Institut des Géosciences de l’Environnement (IGE) Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ) Université Grenoble Alpes (UGA) Université Grenoble Alpes 2020-. Aurélien Dommergue Jennie L. Thomas |
format |
Doctoral or Postdoctoral Thesis |
author |
Ahmed, Shaddy |
author_facet |
Ahmed, Shaddy |
author_sort |
Ahmed, Shaddy |
title |
Modelling Arctic halogen chemistry and its impacts on ozone and mercury |
title_short |
Modelling Arctic halogen chemistry and its impacts on ozone and mercury |
title_full |
Modelling Arctic halogen chemistry and its impacts on ozone and mercury |
title_fullStr |
Modelling Arctic halogen chemistry and its impacts on ozone and mercury |
title_full_unstemmed |
Modelling Arctic halogen chemistry and its impacts on ozone and mercury |
title_sort |
modelling arctic halogen chemistry and its impacts on ozone and mercury |
publisher |
HAL CCSD |
publishDate |
2022 |
url |
https://theses.hal.science/tel-04368946 https://theses.hal.science/tel-04368946/document https://theses.hal.science/tel-04368946/file/AHMED_2022_archivage.pdf |
genre |
Arctique* Sea ice Alaska |
genre_facet |
Arctique* Sea ice Alaska |
op_source |
https://theses.hal.science/tel-04368946 Sciences de la Terre. Université Grenoble Alpes [2020-.], 2022. Français. ⟨NNT : 2022GRALU030⟩ |
op_relation |
NNT: 2022GRALU030 tel-04368946 https://theses.hal.science/tel-04368946 https://theses.hal.science/tel-04368946/document https://theses.hal.science/tel-04368946/file/AHMED_2022_archivage.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1796938371750166528 |