Induction effects on ionospheric electric and magnetic fields
Rapid changes in the ionospheric current system give rise to induction currents in the conducting ground that can significantly contribute to magnetic and especially electric fields at the Earth's surface. Previous studies have concentrated on the surface fields, as they are important in, f...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2005-07-01
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| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/23/1735/2005/angeo-23-1735-2005.pdf |
| _version_ | 1818193287540899840 |
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| author | H. Vanhamäki A. Viljanen O. Amm |
| author_facet | H. Vanhamäki A. Viljanen O. Amm |
| author_sort | H. Vanhamäki |
| collection | DOAJ |
| description | Rapid changes in the ionospheric current system give rise to induction
currents in the conducting ground that can significantly contribute to
magnetic and especially electric fields at the Earth's surface. Previous
studies have concentrated on the surface fields, as they are important in,
for example, interpreting magnetometer measurements or in the studies of the Earth's
conductivity structure. In this paper we investigate the effects of induction
fields at the ionospheric altitudes for several realistic ionospheric current
models (Westward Travelling Surge, Ω-band, Giant Pulsation). Our main
conclusions are: 1) The secondary electric field caused by the Earth's induction is
relatively small at the ionospheric altitude, at most 0.4 mV/m or a few percent of
the total electric field; 2) The primary induced field due to ionospheric
self-induction is locally important, ~ a few mV/m, in some "hot spots",
where the ionospheric conductivity is high and the total electric field is
low. However, our approximate calculation only gives an upper estimate for
the primary induced electric field; 3) The secondary magnetic field caused by
the Earth's induction may significantly affect the magnetic measurements of low
orbiting satellites. The secondary contribution from the Earth's currents is
largest in the vertical component of the magnetic field, where it may be
around 50% of the field caused by ionospheric currents.<p>
<b>Keywords.</b> Geomagnetism and paleomagnetism (geomagnetic
induction) – Ionosphere (electric fields and currents) |
| first_indexed | 2024-12-12T00:44:00Z |
| format | Article |
| id | doaj.art-d690a2f8bc8e429c96f94b56d0049fd2 |
| institution | Directory Open Access Journal |
| issn | 0992-7689 1432-0576 |
| language | English |
| last_indexed | 2024-12-12T00:44:00Z |
| publishDate | 2005-07-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Annales Geophysicae |
| spelling | doaj.art-d690a2f8bc8e429c96f94b56d0049fd22022-12-22T00:44:10ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05762005-07-01231735174610.5194/angeo-23-1735-2005Induction effects on ionospheric electric and magnetic fieldsH. Vanhamäki0A. Viljanen1O. Amm2Finnish Meteorological Institute, Space Research Unit, P.O.Box 503, FI-00101 Helsinki, FinlandFinnish Meteorological Institute, Space Research Unit, P.O.Box 503, FI-00101 Helsinki, FinlandFinnish Meteorological Institute, Space Research Unit, P.O.Box 503, FI-00101 Helsinki, FinlandRapid changes in the ionospheric current system give rise to induction currents in the conducting ground that can significantly contribute to magnetic and especially electric fields at the Earth's surface. Previous studies have concentrated on the surface fields, as they are important in, for example, interpreting magnetometer measurements or in the studies of the Earth's conductivity structure. In this paper we investigate the effects of induction fields at the ionospheric altitudes for several realistic ionospheric current models (Westward Travelling Surge, Ω-band, Giant Pulsation). Our main conclusions are: 1) The secondary electric field caused by the Earth's induction is relatively small at the ionospheric altitude, at most 0.4 mV/m or a few percent of the total electric field; 2) The primary induced field due to ionospheric self-induction is locally important, ~ a few mV/m, in some "hot spots", where the ionospheric conductivity is high and the total electric field is low. However, our approximate calculation only gives an upper estimate for the primary induced electric field; 3) The secondary magnetic field caused by the Earth's induction may significantly affect the magnetic measurements of low orbiting satellites. The secondary contribution from the Earth's currents is largest in the vertical component of the magnetic field, where it may be around 50% of the field caused by ionospheric currents.<p> <b>Keywords.</b> Geomagnetism and paleomagnetism (geomagnetic induction) – Ionosphere (electric fields and currents)https://www.ann-geophys.net/23/1735/2005/angeo-23-1735-2005.pdf |
| spellingShingle | H. Vanhamäki A. Viljanen O. Amm Induction effects on ionospheric electric and magnetic fields Annales Geophysicae |
| title | Induction effects on ionospheric electric and magnetic fields |
| title_full | Induction effects on ionospheric electric and magnetic fields |
| title_fullStr | Induction effects on ionospheric electric and magnetic fields |
| title_full_unstemmed | Induction effects on ionospheric electric and magnetic fields |
| title_short | Induction effects on ionospheric electric and magnetic fields |
| title_sort | induction effects on ionospheric electric and magnetic fields |
| url | https://www.ann-geophys.net/23/1735/2005/angeo-23-1735-2005.pdf |
| work_keys_str_mv | AT hvanhamaki inductioneffectsonionosphericelectricandmagneticfields AT aviljanen inductioneffectsonionosphericelectricandmagneticfields AT oamm inductioneffectsonionosphericelectricandmagneticfields |