 |
| Titel |
Isolated ionospheric disturbances as deduced from global GPS network |
| VerfasserIn |
E. L. Afraimovich, E. I. Astafieva, S. V. Voyeikov |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 22, no. 1 ; Nr. 22, no. 1 (2004-01-01), S.47-62 |
| Datensatznummer |
250014749
|
| Publikation (Nr.) |
 copernicus.org/angeo-22-47-2004.pdf |
|
|
|
|
|
| Zusammenfassung |
We investigate an unusual class of medium-scale traveling
ionospheric disturbances of the nonwave type, isolated
ionospheric disturbances (IIDs) that manifest themselves in total
electron content (TEC) variations in the form of single aperiodic
negative TEC disturbances of a duration of about 10min (the
total electron content spikes, TECS). The data were obtained
using the technology of global detection of ionospheric
disturbances using measurements of TEC variations from a global
network of receivers of the GPS. For the first time, we present
the TECS morphology for 170 days in 1998–2001. The total number of
TEC series, with a duration of each series of about 2.3h (2h18m),
exceeded 850000. It was found that TECS are observed in no more
than 1–2% of the total number of TEC series mainly in the
nighttime in the spring and autumn periods. The TECS amplitude
exceeds the mean value of the "background" TEC variation
amplitude by a factor of 5–10 as a minimum. TECS represent a
local phenomenon with a typical radius of spatial correlation not
larger than 500km. The IID-induced TEC variations are similar in
their amplitude, form and duration to the TEC response to
shock-acoustic waves (SAW) generated during rocket launchings and
earthquakes. However, the IID propagation velocity is less than
the SAW velocity (800–1000m/s) and are most likely to correspond
to the velocity of background medium-scale acoustic-gravity
waves, on the order of 100–200m/s.
Key words. Ionosphere (ionospheric irregularities, instruments and techniques) -
Radio science (ionospheric propagation) |
| |
|
| Teil von |
|
|
|
|
|
|
|
|