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Indian Journal of Radio & Space Physics (IJRSP) >
IJRSP Vol.41 [2012] >
IJRSP Vol.41(2) [April 2012] >
| Title: | Sporadic E over Allahabad during the extremely prolonged low solar activity period of 2007-2009 |
| Authors: | Tiwari, P
Tiwari, D
Surve, G
Nayak, C |
| Keywords: | Sporadic E (Es) layer characteristics
Es layer top frequency (ftEs)
Es layer blanketing frequency (fbEs)
Es layer virtual height
Es layer occurrence
Low solar activity period |
| Issue Date: | Apr-2012 |
| Publisher: | NISCAIR-CSIR, India |
| PACS No.: | 94.20.dg; 96.60.qd |
| Abstract: | In this paper,
the characteristics of sporadic E (Es) layer echoes, observed using a Canadian
Advanced Digital Ionosonde (CADI) from equatorial ionization anomaly crest
region of Allahabad (25.3ºN, 81.5ºE, and dip latitude 16.3ºN) during extremely
prolonged low solar activity period of 2007-2009, have been investigated. Quarter hourly ionograms have been used to
study the Es characteristics, viz. the top frequency reflected by the Es layer
(ftEs), the blanketing frequency (fbEs), virtual height of Es (h’Es) and their
local time and seasonal variations. Also, the occurrence statistics of
Es and total blanketing type Es are presented. The most notable feature of the
sporadic Es layer at Allahabad
is the high percentage occurrence during daytime in the summer months.
Interestingly, observation shows that the occurrence of total blanketing type
Es layer is more during the nighttime of summer months than in other times and
other months. Height migration of h’Es
shows descending pattern indicating the role of tidal winds. These
results are finally compared with those reported earlier and discussed in the
light of current understanding of the solar cycle and seasonal variability of
the temperate latitude Es. |
| Page(s): | 285-293 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-105X (Online); 0367-8393 (Print) |
| Source: | IJRSP Vol.41(2) [April 2012]
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