Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records
Thesis (Ph.D.)--University of Washington, 2015 The formation and recycling of nitrogen oxides (NOx=NO+NO2) associated with snow nitrate photolysis has important implications for air quality and the preservation of nitrate in ice core records. This dissertation examines snow nitrate photolysis in pol...
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ftunivwashington:oai:digital.lib.washington.edu:1773/33570 2023-05-15T13:56:43+02:00 Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records Zatko, Maria Christine Alexander, Becky 2015 application/pdf http://hdl.handle.net/1773/33570 en_US eng Zatko_washington_0250E_15091.pdf http://hdl.handle.net/1773/33570 Copyright is held by the individual authors. GEOS-Chem nitrate NOx ozone photolysis snow Atmospheric chemistry Atmospheric sciences Thesis 2015 ftunivwashington 2023-03-12T18:54:52Z Thesis (Ph.D.)--University of Washington, 2015 The formation and recycling of nitrogen oxides (NOx=NO+NO2) associated with snow nitrate photolysis has important implications for air quality and the preservation of nitrate in ice core records. This dissertation examines snow nitrate photolysis in polar and mid-latitude regions using field and laboratory based observations combined with snow chemistry column models and a global chemical transport model to explore the impacts of snow nitrate photolysis on boundary layer chemistry and the preservation of nitrate in polar ice cores. Chapter 1 describes how a global chemical transport model is used to calculate the photolysis-driven flux and redistribution of nitrogen across Antarctica, and Chapter 2 presents similar work for Greenland. Snow-sourced NOx is most dependent on the quantum yield for nitrate photolysis as well as the concentration of photolabile nitrate and light-absorbing impurities (e.g., black carbon, dust, organics) in snow. Model-calculated fluxes of snow-sourced NOx are similar in magnitude in Antarctica (0.5-7.8x108 molec cm-2 s-1) and Greenland (0.1-6.4x108 molec cm-2 s-1) because both nitrate and light-absorbing impurity concentrations in snow are higher (by factors of 2 and 10, respectively) in Greenland. Snow nitrate photolysis influences boundary layer chemistry and ice-core nitrate preservation less in Greenland compared to Antarctica largely due to Greenland’s proximity to NOx-source regions. Chapter 3 describes how a snow chemistry column model combined with chemistry and optical measurements from the Uintah Basin Winter Ozone Study (UBWOS) 2014 is used to calculate snow-sourced NOx in eastern Utah. Daily-averaged fluxes of snow-sourced NOx (2.9x107-1.3x108 molec cm-2 s-1) are similar in magnitude to polar snow-sourced NOx fluxes, but are only minor components of the Uintah Basin boundary layer NOx budget and can be neglected when developing ozone reduction strategies for the region. Chapter 4 presents chemical and optical measurements ... Thesis Antarc* Antarctica Greenland ice core University of Washington, Seattle: ResearchWorks Greenland |
institution |
Open Polar |
collection |
University of Washington, Seattle: ResearchWorks |
op_collection_id |
ftunivwashington |
language |
English |
topic |
GEOS-Chem nitrate NOx ozone photolysis snow Atmospheric chemistry Atmospheric sciences |
spellingShingle |
GEOS-Chem nitrate NOx ozone photolysis snow Atmospheric chemistry Atmospheric sciences Zatko, Maria Christine Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records |
topic_facet |
GEOS-Chem nitrate NOx ozone photolysis snow Atmospheric chemistry Atmospheric sciences |
description |
Thesis (Ph.D.)--University of Washington, 2015 The formation and recycling of nitrogen oxides (NOx=NO+NO2) associated with snow nitrate photolysis has important implications for air quality and the preservation of nitrate in ice core records. This dissertation examines snow nitrate photolysis in polar and mid-latitude regions using field and laboratory based observations combined with snow chemistry column models and a global chemical transport model to explore the impacts of snow nitrate photolysis on boundary layer chemistry and the preservation of nitrate in polar ice cores. Chapter 1 describes how a global chemical transport model is used to calculate the photolysis-driven flux and redistribution of nitrogen across Antarctica, and Chapter 2 presents similar work for Greenland. Snow-sourced NOx is most dependent on the quantum yield for nitrate photolysis as well as the concentration of photolabile nitrate and light-absorbing impurities (e.g., black carbon, dust, organics) in snow. Model-calculated fluxes of snow-sourced NOx are similar in magnitude in Antarctica (0.5-7.8x108 molec cm-2 s-1) and Greenland (0.1-6.4x108 molec cm-2 s-1) because both nitrate and light-absorbing impurity concentrations in snow are higher (by factors of 2 and 10, respectively) in Greenland. Snow nitrate photolysis influences boundary layer chemistry and ice-core nitrate preservation less in Greenland compared to Antarctica largely due to Greenland’s proximity to NOx-source regions. Chapter 3 describes how a snow chemistry column model combined with chemistry and optical measurements from the Uintah Basin Winter Ozone Study (UBWOS) 2014 is used to calculate snow-sourced NOx in eastern Utah. Daily-averaged fluxes of snow-sourced NOx (2.9x107-1.3x108 molec cm-2 s-1) are similar in magnitude to polar snow-sourced NOx fluxes, but are only minor components of the Uintah Basin boundary layer NOx budget and can be neglected when developing ozone reduction strategies for the region. Chapter 4 presents chemical and optical measurements ... |
author2 |
Alexander, Becky |
format |
Thesis |
author |
Zatko, Maria Christine |
author_facet |
Zatko, Maria Christine |
author_sort |
Zatko, Maria Christine |
title |
Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records |
title_short |
Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records |
title_full |
Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records |
title_fullStr |
Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records |
title_full_unstemmed |
Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records |
title_sort |
snow nitrate photolysis in polar regions and the mid-latitudes: impact on boundary layer chemistry and implications for ice core records |
publishDate |
2015 |
url |
http://hdl.handle.net/1773/33570 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Antarc* Antarctica Greenland ice core |
genre_facet |
Antarc* Antarctica Greenland ice core |
op_relation |
Zatko_washington_0250E_15091.pdf http://hdl.handle.net/1773/33570 |
op_rights |
Copyright is held by the individual authors. |
_version_ |
1766264295398572032 |