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IJRSP Vol.41 [2012] >
IJRSP Vol.41(1) [February 2012] >
| Title: | Diurnal and seasonal variations in sporadic E-layer (Es layer) occurrences over equatorial, low and mid latitude stations - A comparative study |
| Authors: | Prasad, S N V S
Prasad, D S V V D
Venkatesh, K
Niranjan, K
Rao, P V S Rama |
| Keywords: | Ionospheric Disturbances
Sporadic E-layer
Critical Frequency
Blanketing Frequency |
| Issue Date: | Feb-2012 |
| Publisher: | NISCAIR-CSIR, India |
| PACS No.: | 94.20.dg; 94.20.Vv |
| Abstract: | The simultaneous hourly ionograms, from an equatorial station Trivandrum
(8.47°N, 76.91°E), a low latitude station
Waltair (17.70N, 83.3°E) in the Indian sector and a
mid latitude station Kokubunji (35.7°N, 139.5°E) in the Japanese sector during the high sunspot year
2001, are scaled for the study of E-region parameters, namely the virtual
height of sporadic E-layer (h’Es) and the critical frequency of sporadic
E-layer (foEs). The diurnal, seasonal and day-to-day variations in h’Es and
foEs are studied for all the three stations. It is observed that the sporadic
E-layer is absent in the early morning and post sunset hours over Trivandrum during three
different seasons. The values of h’Es are more at Kokubunji as compared to
those at equatorial (Trivandrum)
and low latitude (Waltair) stations during the three different seasons. The
critical frequency of sporadic E-layer (foEs) over Trivandrum shows higher values, compared to
those over Waltair and Kokubunji during daytime hours, in three different
seasons indicating that foEs decrease as the latitude increases. The seasonal
variation in foEs shows higher values during daytime hours of equinox and
winter months over equator (Trivandrum) compared to those over low (Waltair)
and mid (Kokubunji) latitude stations. The variations in h’Es and foEs for
quiet and disturbed conditions indicate that the h’Es variation during quiet
days of equinoctial months at Kokubunji shows a primary peak around morning
hours while it is absent at Waltair and Trivandrum. Further, the behaviour of
blanketing frequency of Es layer fbEs, and foEs-fbEs are also studied. |
| Page(s): | 26-38 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-105X (Online); 0367-8393 (Print) |
| Source: | IJRSP Vol.41(1) [February 2012]
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