Investigating the Physical Mechanisms that Impact Electric Fields in the Atmosphere
The underlying physics and dynamics of the atmosphere drive electric currents and establish electric fields in a phenomenon known as the global electric circuit (GEC). The GEC has been observed and modeled with limiting assumptions and parameterizations in previous research. This thesis describes th...
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ftunicolboulder:oai:scholar.colorado.edu:asen_gradetds-1169 2023-05-15T13:49:40+02:00 Investigating the Physical Mechanisms that Impact Electric Fields in the Atmosphere Lucas, Greg M. 2017-01-01T08:00:00Z application/pdf https://scholar.colorado.edu/asen_gradetds/168 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1169&context=asen_gradetds unknown CU Scholar https://scholar.colorado.edu/asen_gradetds/168 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1169&context=asen_gradetds Aerospace Engineering Sciences Graduate Theses & Dissertations atmospheric electricity clouds and aerosols global climate model global electric circuit Atmospheric Sciences text 2017 ftunicolboulder 2018-10-07T09:03:10Z The underlying physics and dynamics of the atmosphere drive electric currents and establish electric fields in a phenomenon known as the global electric circuit (GEC). The GEC has been observed and modeled with limiting assumptions and parameterizations in previous research. This thesis describes the incorporation of a physics-based GEC modeling scheme into a sophisticated climate model to describe the evolution of GEC currents, ground-ionosphere potential, electric fields, and conductivity within the atmosphere. Supporting measurements of atmospheric electric fields over time were used to describe the impact of local meteorological changes and assess the GEC contribution to near-surface electric fields. The source currents within the GEC are generated by a global distribution of electrified clouds. The produced currents lead to a potential difference between the ground and ionosphere. This potential difference produces return currents that are dependent on the global conductivity distribution. Realistic physics and dynamics produced within the climate model are used to generate the conductivity of the atmosphere. The conductivity calculation includes a 3-D spatial and temporal determination of ion production from radon, galactic cosmic rays, and solar proton events and ion losses from recombination, clouds, and aerosols. To validate the model, several data sets from Antarctica and an array of measurements from Kennedy Space Center were utilized. The use of these data sets required new statistical methods to be developed to better understand how local meteorological processes affect electric fields including the wind direction, clouds, and the local sunrise. Coupling the conductivity and sources together within the model produces new insights into the GEC efficiency of electrical storms. Storms near the equator tend to be strong but inefficient, while storms at mid-latitude are weaker and more efficient. This leads to the global source current distribution shifting more poleward. The model is also used to simulate changes in the GEC caused by volcanic eruptions and the solar cycle. Although the GEC is global in nature, diurnal, seasonal, and annual variations in electric field measurements from the model are highly location dependent. Text Antarc* Antarctica University of Colorado, Boulder: CU Scholar |
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atmospheric electricity clouds and aerosols global climate model global electric circuit Atmospheric Sciences |
spellingShingle |
atmospheric electricity clouds and aerosols global climate model global electric circuit Atmospheric Sciences Lucas, Greg M. Investigating the Physical Mechanisms that Impact Electric Fields in the Atmosphere |
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atmospheric electricity clouds and aerosols global climate model global electric circuit Atmospheric Sciences |
description |
The underlying physics and dynamics of the atmosphere drive electric currents and establish electric fields in a phenomenon known as the global electric circuit (GEC). The GEC has been observed and modeled with limiting assumptions and parameterizations in previous research. This thesis describes the incorporation of a physics-based GEC modeling scheme into a sophisticated climate model to describe the evolution of GEC currents, ground-ionosphere potential, electric fields, and conductivity within the atmosphere. Supporting measurements of atmospheric electric fields over time were used to describe the impact of local meteorological changes and assess the GEC contribution to near-surface electric fields. The source currents within the GEC are generated by a global distribution of electrified clouds. The produced currents lead to a potential difference between the ground and ionosphere. This potential difference produces return currents that are dependent on the global conductivity distribution. Realistic physics and dynamics produced within the climate model are used to generate the conductivity of the atmosphere. The conductivity calculation includes a 3-D spatial and temporal determination of ion production from radon, galactic cosmic rays, and solar proton events and ion losses from recombination, clouds, and aerosols. To validate the model, several data sets from Antarctica and an array of measurements from Kennedy Space Center were utilized. The use of these data sets required new statistical methods to be developed to better understand how local meteorological processes affect electric fields including the wind direction, clouds, and the local sunrise. Coupling the conductivity and sources together within the model produces new insights into the GEC efficiency of electrical storms. Storms near the equator tend to be strong but inefficient, while storms at mid-latitude are weaker and more efficient. This leads to the global source current distribution shifting more poleward. The model is also used to simulate changes in the GEC caused by volcanic eruptions and the solar cycle. Although the GEC is global in nature, diurnal, seasonal, and annual variations in electric field measurements from the model are highly location dependent. |
format |
Text |
author |
Lucas, Greg M. |
author_facet |
Lucas, Greg M. |
author_sort |
Lucas, Greg M. |
title |
Investigating the Physical Mechanisms that Impact Electric Fields in the Atmosphere |
title_short |
Investigating the Physical Mechanisms that Impact Electric Fields in the Atmosphere |
title_full |
Investigating the Physical Mechanisms that Impact Electric Fields in the Atmosphere |
title_fullStr |
Investigating the Physical Mechanisms that Impact Electric Fields in the Atmosphere |
title_full_unstemmed |
Investigating the Physical Mechanisms that Impact Electric Fields in the Atmosphere |
title_sort |
investigating the physical mechanisms that impact electric fields in the atmosphere |
publisher |
CU Scholar |
publishDate |
2017 |
url |
https://scholar.colorado.edu/asen_gradetds/168 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1169&context=asen_gradetds |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
Aerospace Engineering Sciences Graduate Theses & Dissertations |
op_relation |
https://scholar.colorado.edu/asen_gradetds/168 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1169&context=asen_gradetds |
_version_ |
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