|
Titel |
Magnetic local time dependence of geomagnetic disturbances contributing to the AU and AL indices |
VerfasserIn |
S. Tomita, M. Nosé, T. Iyemori, H. Toh, M. Takeda, J. Matzka, G. Bjornsson, T. Saemundsson, A. Janzhura, O. Troshichev, G. Schwarz |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
0992-7689
|
Digitales Dokument |
URL |
Erschienen |
In: Annales Geophysicae ; 29, no. 4 ; Nr. 29, no. 4 (2011-04-14), S.673-678 |
Datensatznummer |
250017003
|
Publikation (Nr.) |
copernicus.org/angeo-29-673-2011.pdf |
|
|
|
Zusammenfassung |
The Auroral Electrojet (AE) indices, which are composed of four indices (AU,
AL, AE, and AO), are calculated from the geomagnetic field data obtained at
12 geomagnetic observatories that are located in geomagnetic latitude (GMLAT)
of 61.7°–70°. The indices have been widely used to study
magnetic activity in the auroral zone. In the present study, we examine
magnetic local time (MLT) dependence of geomagnetic field variations
contributing to the AU and AL indices. We use 1-min geomagnetic field data
obtained in 2003. It is found that both AU and AL indices have two ranges of
MLT (AU: 15:00–22:00 MLT, ~06:00 MLT; and AL: ~02:00 MLT, 09:00–12:00 MLT)
contributing to the index during quiet periods and one MLT range (AU:
15:00–20:00 MLT, and AL: 00:00–06:00 MLT) during disturbed periods. These results
are interpreted in terms of various ionospheric current systems, such as,
Sqp, Sq, and DP2. |
|
|
Teil von |
|
|
|
|
|
|