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

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 O...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Meza, Amalia Margarita, Natali, María Paula, Fernández, Laura Isabel
Formato: Articulo
Lenguaje:Inglés
Publicado: 2015
Materias:
Ciencias Astronómicas
Anomalies
Global IGS VTEC maps
Principal component analysis
Weddell Sea Anomaly
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/86471
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-86471
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Astronómicas
Anomalies
Global IGS VTEC maps
Principal component analysis
Weddell Sea Anomaly
spellingShingle Ciencias Astronómicas
Anomalies
Global IGS VTEC maps
Principal component analysis
Weddell Sea Anomaly
Meza, Amalia Margarita
Natali, María Paula
Fernández, Laura Isabel
PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
topic_facet Ciencias Astronómicas
Anomalies
Global IGS VTEC maps
Principal component analysis
Weddell Sea Anomaly
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.
format Articulo
Articulo
author Meza, Amalia Margarita
Natali, María Paula
Fernández, Laura Isabel
author_facet Meza, Amalia Margarita
Natali, María Paula
Fernández, Laura Isabel
author_sort Meza, Amalia Margarita
title PCA analysis of the nighttime anomaly in far-from-geomagnetic pole regions from VTEC GNSS data
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
publishDate 2015
url http://sedici.unlp.edu.ar/handle/10915/86471
work_keys_str_mv AT mezaamaliamargarita pcaanalysisofthenighttimeanomalyinfarfromgeomagneticpoleregionsfromvtecgnssdata
AT natalimariapaula pcaanalysisofthenighttimeanomalyinfarfromgeomagneticpoleregionsfromvtecgnssdata
AT fernandezlauraisabel pcaanalysisofthenighttimeanomalyinfarfromgeomagneticpoleregionsfromvtecgnssdata
bdutipo_str Repositorios
_version_ 1764820489714270212

Ejemplares similares