Ionospheric Anomalies Observed by GPS-TEC Prior to the 3^rd of July 2013 Uganda’s Earthquake

Enoch Elemo

Centre for Atmospheric Research, Anyigba, Nigeria.

DOI: 10.4236/oalib.1101326                

Abstract

Recently ionospheric variability remains one of the most intensive studies in the area of ionospheric physics. Despite the massive improved knowledge of its dynamics, the ability to use this data to provide early, as well as valid warning of upcoming earthquakes (seismo-ionospheric coupling) is still controversial. However, anomalous behaviours of TEC in the ionosphere before the occurrence of earthquakes have received several attentions by scientists. In this paper, GPS-TEC variations of 31 days (15 days before and 15 days after the occurrence of Uganda’s earthquake of July 3^rd 2013) were examined to see if there was any seismo-ionospheric coupling. Any correlation between the identified TEC anomalies and the earthquake in question was examined. It was discovered that, there was the presence of an anomaly that occurred on the 8^th day of the data. And then there was another set of consistent rise in the TEC values that started 4 days before the day of the earthquake and continued till the day of the earthquake. A change of situation was however noticed after the occurrence of the earthquake. The combination of all these led to the conclusions that the anomaly in the TEC is an ionospheric signature for the earthquake.

Keywords

Ionospheric Variability, Seismo-Ionospheric Coupling, GPS-TEC Variations, Uganda’s Earthquake, Upper Anomalies, Ionospheric Signatures

Conflicts of Interest

The authors declare no conflicts of interest.

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