Refinement of the background ionospheric conditions and plausible explanation based on neutral dynamics for the occurrence/non-occurrence of L-band scintillation patches against forecast.

The impact of the 17 March 2015 St. Patrick's Day storm on the evolutionary pattern of equatorial ionization anomaly over the Indian longitudes using high-resolution spatiotemporal TEC maps: New insights

“…The study related to the comprehensive understanding of EIA forms an active area of research as it affects other geophysical phenomena like the ESF along with its various manifestations in addition to the other notable phenomenon like the equatorial temperature and wind anomaly (ETWA) [ Raghavarao et al ., , ]. While the EIA and ETWA refer to the spatial distribution of F region plasma densities and also the thermospheric parameters like the neutral winds and temperature, the crest to trough ratio of the EIA has been shown to be an important factor toward the forecast of the phenomenon of ESF [ Raghavarao et al ., ; Alex et al ., ; Sridharan et al ., , ; Valladares et al ., ; Thampi et al ., , ; Basu et al ., ]. However, accurate measurement of this ratio relies on the accurate information about the location and longitudinal variation of the EIA crest, which in turn depend on many factors including solar flux, neutral winds, zonal electric fields, and the prevailing geomagnetic conditions.…”

“…The study related to the comprehensive understanding of EIA forms an active area of research as it affects other geophysical phenomena like the ESF along with its various manifestations in addition to the other notable phenomenon like the equatorial temperature and wind anomaly (ETWA) [Raghavarao et al, 1991[Raghavarao et al, , 1993. While the EIA and ETWA refer to the spatial distribution of F region plasma densities and also the thermospheric parameters like the neutral winds and temperature, the crest to trough ratio of the EIA has been shown to be an important factor toward the forecast of the phenomenon of ESF [Raghavarao et al, 1988;Alex et al, 1989;Sridharan et al, 1994Sridharan et al, , 2015 YADAV ET AL. IMPACT Valladares et al, 2001;Thampi et al, 2006Thampi et al, , 2008Basu et al, 2009].…”

Further refinements to the spatiotemporal forecast model for L‐band scintillation based on comparison with C/NOFS observations

“…Further, TEC at 1930 LT, at any location within the equatorial ionization anomaly (EIA) zone, decides the maximum amplitude of the scintillations, namely, the S 4max [ Bagiya et al , ]. The strength of the EIA represented by the crest‐to‐trough ratio has been used as a parameter to provide clues to the favorable/unfavorable conditions for the initiation of the instability [ Raghavarao et al , ; Alex et al , ; Sridharan et al , , ; Valladares et al , ; Thampi et al , , ]. As far as the neutral dynamical parameters controlling the instability are concerned, the vertical winds are known to be capable of tilting the balance [ Sekar and Raghavarao , ; Sridharan et al , , and references therein].…”

VHF Scintillation and Drift Studied Using Spaced Receivers in Southern Taiwan

“…• Statistical characteristics of VHF scintillation and drift have been examined for quiet/disturbed periods during 2015-2017 over China sea • Seasonal asymmetry in the occurrence of scintillation was observed in 2015-2016 but no such asymmetry was apparent in 2017 (low solar) • Disturbed period irregularity drift during moderate geomagnetic storm of 08 September 2017 indicated >200% deviation w.r.t. quiet period important constituent of space research aimed at improving the reliability and integrity of the satellite-based navigation (e.g., Goswami et al, 2017;Sridharan et al, 2015). Owing to the increasing dependence of the mankind on the satellite-based navigation, ionospheric irregularities continue to be extensively studied even after several decades of extensive research on this topic.…”

“…They have achieved remarkable successes in their efforts including its real‐time assessment; however, an operational grade model to forecast the day‐to‐day variability in ionospheric scintillation still requires additional investigations to better understand the generation mechanism of intermediate‐scale irregularities. Thus, investigations to understand the background conditions under which these ionospheric irregularities are generated, remains an important constituent of space research aimed at improving the reliability and integrity of the satellite‐based navigation (e.g., Goswami et al, ; Paul & Paul, ; Sridharan et al, ). Owing to the increasing dependence of the mankind on the satellite‐based navigation, ionospheric irregularities continue to be extensively studied even after several decades of extensive research on this topic.…”