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Chigomezyo M Ngwira - One of the best experts on this subject based on the ideXlab platform.
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A.: 2013, Simulation of the 23 July 2012 extreme space weather event: What if this extremely rare CME was Earth directed? Space Weather 11, 671
DOI. ADS, 2020Co-Authors: Chigomezyo M Ngwira, Antti Pulkkinen, Leila M Mays, A B Galvin, K D C Simunac, D N Baker, Yihua Zheng, Maria M Kuznetsova, Alex GlocerAbstract:[1] Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units ( 1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids
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simulation of the 23 july 2012 extreme space weather event what if this extremely rare cme was earth directed
Social Work, 2013Co-Authors: Antti Pulkkinen, Chigomezyo M Ngwira, Leila M Mays, Maria Kuznetsova, A B Galvin, K D C Simunac, D N Baker, Yihua ZhengAbstract:Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units (∼1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids.
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extended study of extreme Geoelectric Field event scenarios for geomagnetically induced current applications
AGU Fall Meeting Abstracts, 2012Co-Authors: Antti Pulkkinen, Chigomezyo M Ngwira, F D Wilder, G CrowleyAbstract:] Geomagnetically induced currents (GIC) flowing in man-made ground technological systems are adirect manifestation of adverse space weather. Today, there is great concern over possiblegeomagnetically induced current effects on power transmission networks that can result from extremespace weather events. The threat of severe societal consequences has accelerated recent interest inextreme geomagnetic storm impacts on high-voltage power transmission systems. As a result, extremegeomagnetic event characterization is of fundamental importance for quantifying the technologicalimpacts and societal consequences of extreme space weather. This article reports on the global behaviorof the horizontal geomagnetic field and the induced Geoelectric field fluctuations during severe/extremegeomagnetic events. This includes (1) an investigation of the latitude threshold boundary, (2) the localtime dependency of the maximum induced Geoelectric field, and (3) the influence of the equatorialelectrojet (EEJ) current on the occurrence of enhanced induced Geoelectric fields over ground stationslocated near the dip equator. Using ground-based and satellite-borne Defense Meteorological SatelliteProgram measurements, this article confirms that the latitude threshold boundary is associated with themovements of the auroral oval and the corresponding auroral electrojet current system, which is themain driver of the largest perturbations of the ground geomagnetic field at high latitudes. In addition,we show that the enhancement of the EEJ is driven by the penetration of high-latitude electric fields andthat the induced Geoelectric fields at stations within the EEJ belt can be an order of magnitude largerthan that at stations outside the belt. This has important implications for power networks located aroundthe electrojet belt and confirms that earlier observations by Pulkkinen et al. (2012) were not isolatedincidences but rather cases that can occur during certain severe geomagnetic storm events.
Antti Pulkkinen - One of the best experts on this subject based on the ideXlab platform.
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A.: 2013, Simulation of the 23 July 2012 extreme space weather event: What if this extremely rare CME was Earth directed? Space Weather 11, 671
DOI. ADS, 2020Co-Authors: Chigomezyo M Ngwira, Antti Pulkkinen, Leila M Mays, A B Galvin, K D C Simunac, D N Baker, Yihua Zheng, Maria M Kuznetsova, Alex GlocerAbstract:[1] Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units ( 1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids
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predicting global ground Geoelectric Field with coupled geospace and three dimensional geomagnetic induction models
Space Weather-the International Journal of Research and Applications, 2018Co-Authors: Ilja Honkonen, Alexey Kuvshinov, L Rastatter, Antti PulkkinenAbstract:We forecast the global effects of space weather on the Geoelectric and geomagnetic Fields using a novel combination of methods. We use a realistic three-dimensional (3-D) model of Earth's electrical conductivity and a realistic representation of magnetospheric and ionospheric current systems. Our scheme involves the following steps: (1) We run a global magnetohydrodynamic model of the magnetosphere coupled to an electrostatic model of the ionosphere. (2) We calculate a global time series of the ground magnetic Field resulting from the ionospheric, Field-aligned, and magnetospheric currents of the global magnetohydrodynamic model. (3) We approximate this external Field by an equivalent source current flowing in a thin shell above Earth. (4) We calculate a global time series of Geoelectric and geomagnetic Fields from the equivalent current and a 3-D conductivity model of Earth that also takes into account the coast effect due to large horizontal conductivity gradient. We verify our implementation by comparing the results against known analytic and numeric solutions, and then apply our scheme to the geomagnetic storm of 14 and 15 December 2006. In particular, we show that accounting for 3-D structure of Earth's conductivity results in significantly enhanced Geoelectric Field at large lateral gradients of conductivity, especially in coastal regions, both at middle and high latitudes. In the studied geomagnetic storm the largest values of 3-D Geoelectric Field are detected at high latitudes reaching 2.5 volts per kilometer and the 3-D effect extends inland by a few hundred kilometers.
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simulation of the 23 july 2012 extreme space weather event what if this extremely rare cme was earth directed
Social Work, 2013Co-Authors: Antti Pulkkinen, Chigomezyo M Ngwira, Leila M Mays, Maria Kuznetsova, A B Galvin, K D C Simunac, D N Baker, Yihua ZhengAbstract:Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units (∼1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids.
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extended study of extreme Geoelectric Field event scenarios for geomagnetically induced current applications
AGU Fall Meeting Abstracts, 2012Co-Authors: Antti Pulkkinen, Chigomezyo M Ngwira, F D Wilder, G CrowleyAbstract:] Geomagnetically induced currents (GIC) flowing in man-made ground technological systems are adirect manifestation of adverse space weather. Today, there is great concern over possiblegeomagnetically induced current effects on power transmission networks that can result from extremespace weather events. The threat of severe societal consequences has accelerated recent interest inextreme geomagnetic storm impacts on high-voltage power transmission systems. As a result, extremegeomagnetic event characterization is of fundamental importance for quantifying the technologicalimpacts and societal consequences of extreme space weather. This article reports on the global behaviorof the horizontal geomagnetic field and the induced Geoelectric field fluctuations during severe/extremegeomagnetic events. This includes (1) an investigation of the latitude threshold boundary, (2) the localtime dependency of the maximum induced Geoelectric field, and (3) the influence of the equatorialelectrojet (EEJ) current on the occurrence of enhanced induced Geoelectric fields over ground stationslocated near the dip equator. Using ground-based and satellite-borne Defense Meteorological SatelliteProgram measurements, this article confirms that the latitude threshold boundary is associated with themovements of the auroral oval and the corresponding auroral electrojet current system, which is themain driver of the largest perturbations of the ground geomagnetic field at high latitudes. In addition,we show that the enhancement of the EEJ is driven by the penetration of high-latitude electric fields andthat the induced Geoelectric fields at stations within the EEJ belt can be an order of magnitude largerthan that at stations outside the belt. This has important implications for power networks located aroundthe electrojet belt and confirms that earlier observations by Pulkkinen et al. (2012) were not isolatedincidences but rather cases that can occur during certain severe geomagnetic storm events.
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geomagnetic storm of 29 31 october 2003 geomagnetically induced currents and their relation to problems in the swedish high voltage power transmission system
Social Work, 2005Co-Authors: Antti Pulkkinen, A Viljanen, Sture Lindahl, Risto PirjolaAbstract:On 30 October 2003, an ongoing geomagnetic superstorm knocked down a part of the high- voltage power transmission system in southern Sweden. The blackout lasted for an hour and left about 50,000 customers without electricity. The incident was probably the most severe geomagnetically induced current ( GIC) failure observed since the well- known March 1989 Quebec blackout. The " three- phase'' storm produced exceptionally large geomagnetic activity at the Fennoscandian auroral region. Although the diversity of the GIC drivers is addressed in the study, the problems in operating the Swedish system during the storm are attributed geophysically to substorms, storm sudden commencement, and enhanced ionospheric convection, all of which created large and complex Geoelectric Fields capable of driving large GIC. On the basis of the basic twofold nature of the failure- related Geoelectric Field characteristics, a semideterministic approach for forecasting GIC- related geomagnetic activity in which average overall activity is supplemented with statistical estimations of the amplitudes of GIC fluctuations is suggested. The study revealed that the primary mode of GIC- related failures in the Swedish high- voltage power transmission system were via harmonic distortions produced by GIC combined with too sensitive operation of the protective relays. The outage in Malmo " on 30 October 2003 was caused by a combination of an abnormal switching state of the system and tripping of a low- set residual overcurrent relay that had a high sensitivity for the third harmonic of the fundamental frequency. (Less)
Yihua Zheng - One of the best experts on this subject based on the ideXlab platform.
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A.: 2013, Simulation of the 23 July 2012 extreme space weather event: What if this extremely rare CME was Earth directed? Space Weather 11, 671
DOI. ADS, 2020Co-Authors: Chigomezyo M Ngwira, Antti Pulkkinen, Leila M Mays, A B Galvin, K D C Simunac, D N Baker, Yihua Zheng, Maria M Kuznetsova, Alex GlocerAbstract:[1] Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units ( 1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids
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simulation of the 23 july 2012 extreme space weather event what if this extremely rare cme was earth directed
Social Work, 2013Co-Authors: Antti Pulkkinen, Chigomezyo M Ngwira, Leila M Mays, Maria Kuznetsova, A B Galvin, K D C Simunac, D N Baker, Yihua ZhengAbstract:Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units (∼1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids.
Leila M Mays - One of the best experts on this subject based on the ideXlab platform.
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A.: 2013, Simulation of the 23 July 2012 extreme space weather event: What if this extremely rare CME was Earth directed? Space Weather 11, 671
DOI. ADS, 2020Co-Authors: Chigomezyo M Ngwira, Antti Pulkkinen, Leila M Mays, A B Galvin, K D C Simunac, D N Baker, Yihua Zheng, Maria M Kuznetsova, Alex GlocerAbstract:[1] Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units ( 1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids
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simulation of the 23 july 2012 extreme space weather event what if this extremely rare cme was earth directed
Social Work, 2013Co-Authors: Antti Pulkkinen, Chigomezyo M Ngwira, Leila M Mays, Maria Kuznetsova, A B Galvin, K D C Simunac, D N Baker, Yihua ZhengAbstract:Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units (∼1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids.
A B Galvin - One of the best experts on this subject based on the ideXlab platform.
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A.: 2013, Simulation of the 23 July 2012 extreme space weather event: What if this extremely rare CME was Earth directed? Space Weather 11, 671
DOI. ADS, 2020Co-Authors: Chigomezyo M Ngwira, Antti Pulkkinen, Leila M Mays, A B Galvin, K D C Simunac, D N Baker, Yihua Zheng, Maria M Kuznetsova, Alex GlocerAbstract:[1] Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units ( 1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids
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simulation of the 23 july 2012 extreme space weather event what if this extremely rare cme was earth directed
Social Work, 2013Co-Authors: Antti Pulkkinen, Chigomezyo M Ngwira, Leila M Mays, Maria Kuznetsova, A B Galvin, K D C Simunac, D N Baker, Yihua ZhengAbstract:Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units (∼1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic Field perturbations are used to compute the simulated induced Geoelectric Field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric Fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids.
