| Full text | |
| Author(s): |
Venkatesh, K.
[1]
;
Patra, A. K.
[1]
;
Balan, N.
[2]
;
Fagundes, P. R.
[3]
;
Ram, S. Tulasi
[4]
;
Batista, I. S.
[5]
;
Reinisch, B. W.
[6]
Total Authors: 7
|
| Affiliation: | [1] Natl Atmospher Res Lab, Gadanki - India
[2] Shandong Univ, Inst Space Sci, Weihai - India
[3] Univ Vale Paraiba, IP&D, Sao Paulo - Brazil
[4] Indian Inst Geomagnetism, Navi Mumbai - India
[5] Inst Nacl Pesquisas Espaciais, Sao Paulo - Brazil
[6] Lowell Digisonde Int, Lowell, MA - USA
Total Affiliations: 6
|
| Document type: | Journal article |
| Source: | JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS; v. 124, n. 7, p. 6127-6137, JUL 2019. |
| Web of Science Citations: | 1 |
| Abstract | |
The existence of an additional stratification in the daytime equatorial ionospheric F region (the F-3 layer) was known since the 1940s. However, its characteristics and the underlying physical mechanism have been uncovered only recently. In this paper, we present and discuss the F-3 layer characteristics observed by six ionosondes distributed over equatorial and low latitudes (-20 degrees to +25 degrees dip latitudes) in the Brazilian longitude sector during the strongest geomagnetic storm (DstMin = -223 nT) of solar cycle 24, the St. Patrick's Day storm of 17 March 2015. Two eastward prompt penetration electric field (PPEF) events, as seen in equatorial electrojet, occurred during the main phase of the storm on 17 March 2015, a strong one (similar to 100 nT) at around similar to 1200 UT and a weak one (similar to 50 nT) at around similar to 1725 UT. Local time variations in the F-3 layer occurrence and ionospheric base height (h'F), peak height (hmF), and peak electron density (Nmax) are investigated. Notably, the F-3 layer occurred at all six locations, more distinctly during the stronger PPEF event. The large latitudinal extend in the occurrence of the F-3 layer in opposite hemispheres (-20 degrees to +25 degrees dip latitudes) covering the equatorial ionization anomaly crests observed for the first time is interpreted in terms of the combined effect of the super plasma fountain generated by the eastward PPEF and storm time equatorward neutral wind. (AU) | |
| FAPESP's process: | 12/08445-9 - Study of day-to-day variability of the mesosphere, thermosphere and ionosphere at low latitude and equatorial region, during the solar cycle 24 |
| Grantee: | Paulo Roberto Fagundes |
| Support Opportunities: | Research Projects - Thematic Grants |