Earthquake Time Low Latitude Tec and Model Estimated Values: Identification on Earthquake Induced Atmospheric Dynamics

Adaptive techniques for extraction of pre-seismic parameters of Total Electron Content (TEC) at anomaly crest station

“…Thus, the above reports highlight the facts that earthquake induced modification in TEC around the low latitude zone is complex. This fact is also noted by Devi et al (2010b) in the evaluation of pre-seismic TEC parameters, through a model like the International Reference Ionosphere (IRI). It was reported by them that even after they inserted the values of the 'F-region peak ionization density' appropriate to 'earthquake time situations' into the model, the computed outcome falls short to conform with the observed high TEC peak .…”

“…In the next paragraph, utilization aspects of the 'shape of TEC profile' in this context are presented. The TEC profile shape is now brought into consideration for its possible use as another marker for precursor, because it is expected that the alteration in shape is forced on it by pre-earthquake processes (Depueva and Rotanova 2001, Devi et al 2004, 2010b. The profile shape is also subjected to changes by other factors, of these the solar geomagnetic ambience is most important (Devi et al 2002).…”

“…Most of the low latitude earthquake precursor related reports are based on changes in TEC peak value (Devi et al 2001, Singh et al 2009), but the results sometimes fail to mark a cursor (Devi et al 2010b). In this paper therefore, an approach is presented where modifications forced into the entire TEC profile by earthquake preparatory processes are brought to focus, in addition to a single parameter as the TEC peak.…”

“…Devi et al Devi et al 2004Devi et al , 2010b. It is shown by Devi et al (2010b) that low-latitude earthquakes also force similar changes on profiles of electron density, though the modifications may extend to beyond the day peak.…”

“…Devi et al Devi et al 2004Devi et al , 2010b. It is shown by Devi et al (2010b) that low-latitude earthquakes also force similar changes on profiles of electron density, though the modifications may extend to beyond the day peak. Thus, modifications to electron content imposed by an equatorial earthquake may not be similar to that of a low latitude one, when shifts of the anomaly crest may lead to either an increase or decrease of TEC, depending in a complex way on magnitude of the earthquake, proximity of the epicentre to the observing station and the simultaneous presence of an equatorial earthquake (Devi et al 2010b).…”