PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data

Autores
Meza, Amalia Margarita; Natali, María Paula; Fernández, Laura Isabel
Año de publicación
2015
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
The Weddell Sea Anomaly (WSA) is defined when the nighttime plasma density is greater than the daytime density in the area near the Weddell Sea, more specifically in the region limited by 50° S-70°S in latitude and 225° E-315° E in longitude. A similar ionospheric anomaly is also observed near the Okhotsk Sea in the northern hemisphere, and such a feature was named as Okhotsk Sea Anomaly (OSA). The objective of this work is to infer possible physical causes of the WSA and OSA phenomena. To that end, we applied the principal component analysis (PCA) technique to the vertical total electron content (VTEC) from global International GNSS Service (IGS) in order to analyze the temporal and spatial variations of the ionosphere during noon and night in far-from-magnetic pole regions, during a 3-year period at high (2000-2002) and low (2006-2008) solar activity conditions. The first mode of PCA applied on VTEC scattering represents on average the 93 % of the total VTEC variability. Thus, the PCA expansions up to mode 1 resulted enough to show WSA and OSA during summer solstices in both solar activity conditions, as well as WSA during spring equinox during low solar activity. Besides, the analysis of the temporal variations of these first modes should provide the interpretation of a probable physical explanation to the observed anomalies. We conclude that the main contributors to the anomalies should be a combination of the same physical mechanisms that explain annual variation and semiannual anomaly in that regions located far from the magnetic poles.
Facultad de Ciencias Astronómicas y Geofísicas
Materia
Ciencias Astronómicas
Anomalies
Global IGS VTEC maps
Principal component analysis
Weddell Sea Anomaly
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by-nc-sa/4.0/
Repositorio
SEDICI (UNLP)
Institución
Universidad Nacional de La Plata
OAI Identificador
oai:sedici.unlp.edu.ar:10915/86471

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network_name_str SEDICI (UNLP)
spelling PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS dataMeza, Amalia MargaritaNatali, María PaulaFernández, Laura IsabelCiencias AstronómicasAnomaliesGlobal IGS VTEC mapsPrincipal component analysisWeddell Sea AnomalyThe Weddell Sea Anomaly (WSA) is defined when the nighttime plasma density is greater than the daytime density in the area near the Weddell Sea, more specifically in the region limited by 50° S-70°S in latitude and 225° E-315° E in longitude. A similar ionospheric anomaly is also observed near the Okhotsk Sea in the northern hemisphere, and such a feature was named as Okhotsk Sea Anomaly (OSA). The objective of this work is to infer possible physical causes of the WSA and OSA phenomena. To that end, we applied the principal component analysis (PCA) technique to the vertical total electron content (VTEC) from global International GNSS Service (IGS) in order to analyze the temporal and spatial variations of the ionosphere during noon and night in far-from-magnetic pole regions, during a 3-year period at high (2000-2002) and low (2006-2008) solar activity conditions. The first mode of PCA applied on VTEC scattering represents on average the 93 % of the total VTEC variability. Thus, the PCA expansions up to mode 1 resulted enough to show WSA and OSA during summer solstices in both solar activity conditions, as well as WSA during spring equinox during low solar activity. Besides, the analysis of the temporal variations of these first modes should provide the interpretation of a probable physical explanation to the observed anomalies. We conclude that the main contributors to the anomalies should be a combination of the same physical mechanisms that explain annual variation and semiannual anomaly in that regions located far from the magnetic poles.Facultad de Ciencias Astronómicas y Geofísicas2015info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfhttp://sedici.unlp.edu.ar/handle/10915/86471enginfo:eu-repo/semantics/altIdentifier/issn/1343-8832info:eu-repo/semantics/altIdentifier/doi/10.1186/s40623-015-0281-4info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:16:50Zoai:sedici.unlp.edu.ar:10915/86471Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:16:50.663SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
title PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
spellingShingle PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
Meza, Amalia Margarita
Ciencias Astronómicas
Anomalies
Global IGS VTEC maps
Principal component analysis
Weddell Sea Anomaly
title_short PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
title_full PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
title_fullStr PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
title_full_unstemmed PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
title_sort PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
dc.creator.none.fl_str_mv Meza, Amalia Margarita
Natali, María Paula
Fernández, Laura Isabel
author Meza, Amalia Margarita
author_facet Meza, Amalia Margarita
Natali, María Paula
Fernández, Laura Isabel
author_role author
author2 Natali, María Paula
Fernández, Laura Isabel
author2_role author
author
dc.subject.none.fl_str_mv Ciencias Astronómicas
Anomalies
Global IGS VTEC maps
Principal component analysis
Weddell Sea Anomaly
topic Ciencias Astronómicas
Anomalies
Global IGS VTEC maps
Principal component analysis
Weddell Sea Anomaly
dc.description.none.fl_txt_mv The Weddell Sea Anomaly (WSA) is defined when the nighttime plasma density is greater than the daytime density in the area near the Weddell Sea, more specifically in the region limited by 50° S-70°S in latitude and 225° E-315° E in longitude. A similar ionospheric anomaly is also observed near the Okhotsk Sea in the northern hemisphere, and such a feature was named as Okhotsk Sea Anomaly (OSA). The objective of this work is to infer possible physical causes of the WSA and OSA phenomena. To that end, we applied the principal component analysis (PCA) technique to the vertical total electron content (VTEC) from global International GNSS Service (IGS) in order to analyze the temporal and spatial variations of the ionosphere during noon and night in far-from-magnetic pole regions, during a 3-year period at high (2000-2002) and low (2006-2008) solar activity conditions. The first mode of PCA applied on VTEC scattering represents on average the 93 % of the total VTEC variability. Thus, the PCA expansions up to mode 1 resulted enough to show WSA and OSA during summer solstices in both solar activity conditions, as well as WSA during spring equinox during low solar activity. Besides, the analysis of the temporal variations of these first modes should provide the interpretation of a probable physical explanation to the observed anomalies. We conclude that the main contributors to the anomalies should be a combination of the same physical mechanisms that explain annual variation and semiannual anomaly in that regions located far from the magnetic poles.
Facultad de Ciencias Astronómicas y Geofísicas
description The Weddell Sea Anomaly (WSA) is defined when the nighttime plasma density is greater than the daytime density in the area near the Weddell Sea, more specifically in the region limited by 50° S-70°S in latitude and 225° E-315° E in longitude. A similar ionospheric anomaly is also observed near the Okhotsk Sea in the northern hemisphere, and such a feature was named as Okhotsk Sea Anomaly (OSA). The objective of this work is to infer possible physical causes of the WSA and OSA phenomena. To that end, we applied the principal component analysis (PCA) technique to the vertical total electron content (VTEC) from global International GNSS Service (IGS) in order to analyze the temporal and spatial variations of the ionosphere during noon and night in far-from-magnetic pole regions, during a 3-year period at high (2000-2002) and low (2006-2008) solar activity conditions. The first mode of PCA applied on VTEC scattering represents on average the 93 % of the total VTEC variability. Thus, the PCA expansions up to mode 1 resulted enough to show WSA and OSA during summer solstices in both solar activity conditions, as well as WSA during spring equinox during low solar activity. Besides, the analysis of the temporal variations of these first modes should provide the interpretation of a probable physical explanation to the observed anomalies. We conclude that the main contributors to the anomalies should be a combination of the same physical mechanisms that explain annual variation and semiannual anomaly in that regions located far from the magnetic poles.
publishDate 2015
dc.date.none.fl_str_mv 2015
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Articulo
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://sedici.unlp.edu.ar/handle/10915/86471
url http://sedici.unlp.edu.ar/handle/10915/86471
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/1343-8832
info:eu-repo/semantics/altIdentifier/doi/10.1186/s40623-015-0281-4
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
dc.format.none.fl_str_mv application/pdf
dc.source.none.fl_str_mv reponame:SEDICI (UNLP)
instname:Universidad Nacional de La Plata
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reponame_str SEDICI (UNLP)
collection SEDICI (UNLP)
instname_str Universidad Nacional de La Plata
instacron_str UNLP
institution UNLP
repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
repository.mail.fl_str_mv alira@sedici.unlp.edu.ar
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