 |
| Titel |
ULF wave occurrence statistics in a high-latitude HF Doppler sounder |
| VerfasserIn |
D. M. Wright, T. K. Yeoman, T. B. Jones |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 17, no. 6 ; Nr. 17, no. 6, S.749-758 |
| Datensatznummer |
250013773
|
| Publikation (Nr.) |
 copernicus.org/angeo-17-749-1999.pdf |
|
|
|
|
|
| Zusammenfassung |
Ultra low frequency (ULF) wave activity in
the high-latitude ionosphere has been observed by a high frequency (HF) Doppler
sounder located at Tromsø, Norway (69.7°N, 19.2°E geographic coordinates). A
statistical study of the occurrence of these waves has been undertaken from data
collected between 1979 and 1984. The diurnal, seasonal, solar cycle and
geomagnetic activity variations in occurrence have been investigated. The
findings demonstrate that the ability of the sounder to detect ULF wave
signatures maximises at the equinoxes and that there is a peak in occurrence in
the morning sector. The occurrence rate is fairly insensitive to changes
associated with the solar cycle but increases with the level of geomagnetic
activity. As a result, it has been possible to characterise the way in which
prevailing ionospheric and magnetospheric conditions affect such observations of
ULF waves.
Key words. Ionosphere (auroral ionosphere;
ionosphere -magnetosphere interactions) · Magnetospheric physics (MHD waves and
instabilities) |
| |
|
| Teil von |
|
|
|
|
|
|
|
|