 |
| Titel |
Annual and semiannual variations of vertical total electron content during high solar activity based on GPS observations |
| VerfasserIn |
M. P. Natali, A. Meza |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 29, no. 5 ; Nr. 29, no. 5 (2011-05-18), S.865-873 |
| Datensatznummer |
250017020
|
| Publikation (Nr.) |
 copernicus.org/angeo-29-865-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
Annual, semiannual and seasonal variations of the Vertical Total Electron
Content (VTEC) have been investigated during high solar activity in 2000. In
this work we use Global IGS VTEC maps and Principal Component Analysis to
study spatial and temporal ionospheric variability. The behavior of VTEC
variations at two-hour periods, at noon and at night is analyzed. Particular
characteristics associated with each period and the geomagnetic regions are
highlighted.
The variations at night are smaller than those obtained at noon. At noon it
is possible to see patterns of the seasonal variation at high latitude, and
patterns of the semiannual anomaly at low latitudes with a slow decrease
towards mid latitudes. At night there is no evidence of seasonal or annual
anomaly for any region, but it was possible to see the semiannual anomaly at
low latitudes with a sudden decrease towards mid latitudes. In general, the
semiannual behavior shows March–April equinox at least 40 % higher than
September one. Similarities and differences are analyzed also with regard to
the same analysis done for a period of low solar activity. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|