Please use this identifier to cite or link to this item:
Title: foF2 variations during geomagnetic disturbances at the rise of solar cycle 23
Authors: Adebesin, B Olufemi
Keywords: F2 layer critical frequency;Geomagnetic disturbances;Solar radiance;Solar cycle 23;Electron density
Issue Date: Jun-2012
Publisher: NISCAIR-CSIR, India
PACS No.: 91.25.Rt;; 94.20.Vv
Abstract: The present work emphasizes on foF2, the critical frequency of the F2 layer, variations during peak geomagnetic disturbances (Dst ≤ -100 nT) at the rise of solar cycle 23. Geomagnetic, interplanetary and solar wind parameters have been studied as well as foF2 data from five ionosonde stations in the Asian sector. The study shows that: (i) the observed enhancement immediately after sunset at Petropavlovsk compared with foF2 upwelling after sunrise at Magadan after the storm on 12 February 2000 revealed that there is no simultaneity in foF2 during the activity, (ii) the variation of foF2 along a line of fixed latitude, as it occurs at four stations during the 12 August 2000 storm, shows the diurnal anomaly, which depends on the season and epoch of the solar cycle, reaching maximum before sunrise, and (iii) at any latitude, factors other than solar radiance play an important role in determining the foF2 variations. The results seem to agree with earlier works. The morphology of both positive and negative phase storms is also discussed.
Page(s): 323-331
ISSN: 0975-105X (Online); 0367-8393 (Print)
Appears in Collections:IJRSP Vol.41(3) [June 2012]

Files in This Item:
File Description SizeFormat 
IJRSP 41(3) 323-331.pdf288.08 kBAdobe PDFView/Open

Items in NOPR are protected by copyright, with all rights reserved, unless otherwise indicated.