Sporadic-E ionization over Ahmedabad through the half solar cycle 1954–1957

Kotadia, K. M.

doi:10.1016/0021-9169(69)90050-6

Cited by 8 publications

(5 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As it was mentioned in the Introduction, although the influence of solar activity on Es layer has already been investigated by many authors (Bossolasco & Elena 1963;Kotadia 1969;Baggaley 1984;Whitehead 1989;Maksyutin et al 2001;Pietrella & Bianchi 2009;Pietrella et al 2014), it is still a topic of debate. This is why we think that this work could be important, because the analyses shown in this paper, which are surely more refined than the previous studies on the subject, show beyond any doubt that the daytime Es layer is positively correlated with the solar activity, a result which is an unequivocal proof in support of the influence of solar activity on Es layer.…”

mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

“…The majority of works debated this issue in terms of Es occurrence percentages, with limiting varying values of the critical frequency of the Es ordinary mode of propagation (foEs) (Kotadia 1969;Baggaley 1984;Pietrella & Bianchi 2009). Kotadia (1969), who considered less than half a solar cycle data, found a negative correlation between the Es occurrence and the solar activity. Baggaley (1984) while analysing data covering three solar cycles, that were recorded at two stations located in the southern hemisphere, found a positive correlation between the long-term occurrences of the blanketing frequency of Es layer (fbEs) and the Zurich sunspot number R z , but he did not find any correlation for foEs.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

On the influence of solar activity on the mid-latitude sporadic E layer

Pezzopane

Pignalberi

Pietrella

2015

J. Space Weather Space Clim.

View full text Add to dashboard Cite

To investigate the influence of solar cycle variability on the sporadic E layer (Es), hourly measurements of the critical frequency of the Es ordinary mode of propagation, foEs, and of the blanketing frequency of the Es layer, fbEs, recorded from January 1976 to December 2009 at the Rome (Italy) ionospheric station (41.8°N, 12.5°E), were examined. The results are: (1) a high positive correlation between the F10.7 solar index and foEs as well as between F10.7 and fbEs, both for the whole data set and for each solar cycle separately, the correlation between F10.7 and fbEs being much higher than the one between F10.7 and foEs; (2) a decreasing long-term trend of the F10.7, foEs and fbEs time series, with foEs decreasing more rapidly than F10.7 and fbEs; (3) clear and statistically significant peaks at 11 years in the foEs and fbEs time series, inferred from Lomb-Scargle periodograms.

show abstract

mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

On the influence of solar activity on the mid-latitude sporadic E layer

Pezzopane

Pignalberi

Pietrella

2015

J. Space Weather Space Clim.

View full text Add to dashboard Cite

show abstract

“…Due to the close relation between E‐region FAI and local E S layer, the geomagnetic and solar dependencies of E‐region FAI occurrence may be associated with the geomagnetic and solar variations of local E S occurrence. Observations of ionosondes have suggested that midlatitude E S occurrence has distinct geomagnetic and solar variations (Baggaley, 1984; Kotadia, 1969; Tan et al., 1985; Zhang et al., 2015). Zhou et al.…”

Section: Introductionmentioning

confidence: 99%

“…FAI and local E S layer, the geomagnetic and solar dependencies of E-region FAI occurrence may be associated with the geomagnetic and solar variations of local E S occurrence. Observations of ionosondes have suggested that midlatitude E S occurrence has distinct geomagnetic and solar variations (Baggaley, 1984;Kotadia, 1969;Tan et al, 1985;Zhang et al, 2015). Zhou et al (2017) showed the positive correction between E S occurrence and the level of geomagnetic activity observed by ionosondes located at Mohe, Beijing, Wuhan, and Hainan.…”

mentioning

confidence: 96%

Geomagnetic and Solar Dependencies of Midlatitude E‐Region Irregularity Occurrence Rate: A Climatology Based on Wuhan VHF Radar Observations

Liu

Zhou

et al. 2022

JGR Space Physics

View full text Add to dashboard Cite

By using Wuhan VHF radar, we show the morphological features of E‐region field‐aligned irregularity (FAI) occurrence at Wuhan during 2015–2020. Statistical results present that E‐region FAI occurrence reaches a maximum after sunset in summer season. According to Doppler spectrum features, type‐2 irregularity is predominantly observed at Wuhan. In addition, we observed a remarkable correlation between E‐region FAI occurrence and geomagnetic activity, which includes periods of positive correlation and negative correlation depending on different geomagnetic conditions. The strong negative correlation also exists between E‐region FAI occurrence and solar activity. In our observed results, we find that E‐region FAI occurrence shows a strong linkage with local sporadic E (ES) layer. A quantitative analysis of linear theory of plasma instability in the E‐region at midlatitudes is also presented in our study. The calculated results of linear growth rate indicate the importance of plasma density gradient of local ES layer and field‐line‐integrated Pedersen conductivity ΣPE+F ${{\Sigma}}_{P}^{E+F}$ on the generation of E‐region FAI. The geomagnetic and solar variations of E‐region FAI occurrence are also discussed in this study, which show a dependence on the geomagnetic and solar variations of both meteor rate and medium‐scale traveling ionospheric disturbance occurrence.

show abstract