TITLE:
Ionospheric Anomalies around the Time of the Powerful Nabro’s Eruption Triggered by June 12, 2011 Earthquakes
AUTHORS:
Enoch Oluwaseun Elemo
KEYWORDS:
Ionospheric Variability, Seismo-Ionospheric Couplings, Earthquake, GPS-TEC Data, TEC Anomalies and Eruption
JOURNAL NAME:
Open Access Library Journal,
Vol.2 No.6,
June
5,
2015
ABSTRACT:
Ionospheric variability resulting from earthquake events is a known
phenomenon as revealed by various seismo-ionospheric coupling studies.
Variations resulting from seismo-ionospheric couplings are known to be much
weaker, and noted to occur only locally in an area that is specified by the
magnitude of the earthquake. Whereas disturbances generated by other sources
like geomagnetic storms, exhibit a more global behaviour. For this study,
GPS-TEC data of 31 days (15 days before and 15 days after the occurrence of
June 12, 2011 earthquakes) were examined. There were 14 earthquakes within 6 hours
of that day that triggered the eruption that occurred on the 19th and 20th.
This eruption produced the highest level of sulfur dioxide emissions in the
earth’s atmosphere that was ever detected from space. Any correlation between the identified TEC anomalies and the earthquakes
were examined. The results showed an anomaly which started two days before the
earthquakes. There was a consistent decrease in the GPS-TEC two days before the
earthquake. The day of the earthquake also witnessed the most anomalous decrease
during the days understudy. The 19th day of June 2011 eruptions however
reflected in the ionosphere through the decrease in electron concentrations.