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 3rd 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 8th 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.
Cite this paper
Elemo, E. (2015). Ionospheric Anomalies Observed by GPS-TEC Prior to the 3rd of July 2013 Uganda’s Earthquake. Open Access Library Journal, 2, e1326. doi: http://dx.doi.org/10.4236/oalib.1101326.
Hayakawa, M., Molchanov, O.A., Kodama, T., Afonin, V.V. and Akentieva, O.A. (2000) Plasma Density
Variations Observed on a Satellite Possibly Related to Seismicity.Advances in
Space Research, 26, 1277-1280. http://dx.doi.org/10.1016/S0273-1177(99)01224-7
Liu, J.Y.,
Chen, Y.I., Jhuang, H.K. and Lin, Y.H. (2004) Ionospheric f0F2 and TEC Anomalous Days
Associated with M ≥ 5.0 Earthquakes in Taiwan during 1997-1999. Terrestrial
Atmospheric and Oceanic Sciences, 15, 371-383.
Liu, J.Y., Chen, Y.I. and Chen, C.H. (2009) Seismoionospheric GPS Total Electron
Content Anomalies Observed before the 12 May 2008 Mw 7.9 Wenchuan Earthquake. Journal of Geophysical Research A, 114, Article ID A04320.
Liu, J.Y., Chen, Y.I., Chuo, Y.J. and
Tsai, H.F. (2001) Variations of Ionospheric
Total Content during the Chi-Chi Earthquake. Geophysical Research Letters, 28,
1381-1386. http://dx.doi.org/10.1029/2000GL012511
Liu, J.Y., Tsai, Y.B. and Ma, K.F. (2006) Precursory Phenomena Associated with the
1999 Chi-Chi Earthquake in Taiwan as Identified under the iSTEP Program. Physics and Chemistry of the Earth,
31, 365-377.
Pulinets, S.A., Khegai, V.V., Boyarchuk, K.A. and Lomonosov, A.M. (1998) Atmospheric Electric Field as a Source of
Ionospheric Variability. Physics-Uspekhi, 41, 515-522. http://dx.doi.org/10.1070/PU1998v041n05ABEH000399
Pulinets, S.A., Hernandez-Pajares, M. and
Depuev, V.K.H. (2003) Equatorial
Anomaly Variability as a Function of the Local Time and the Longitude. Proceedings of the IRI
Task Force Activity, Trieste,
159-166.
Zakharenkova, I.E., Shagimuratov, I.I. and Tepenitzina, N.Yu. (2008) Anomalous Modification of the Ionospheric
Total Electron Content Prior to the 26 September 2005 Peru Earthquake. Journal
of Atmospheric and Solar-Terrestrial Physics, 70, 1919-1928. http://dx.doi.org/10.1016/j.jastp.2008.06.003
Liu, L., Wan,
W., Zhang, M.L., Zhao, B. and Ning, B. (2008) Prestorm Enhancement in NmF2 and Total Electron Content at Low
Latitudes.Journal
of Geophysical Research, 113, A02311. http://dx.doi.org/10.1029/2007JA012832
Zhao, B.Q.,
Wang, M. and Yu, T. (2008) Is an Unusual Large Enhancement of Ionospheric
Electron Density Linked with the 2008 Great Wenchuan Earthquake? Journal of Geophysical Research, 113, A11304. http://dx.doi.org/10.1029/2008JA013613
Fujinawa,
Y. and Tkahashi, K. (1990) Emission of
Electromagnetic Radiation Preceeding the Ito Seismc Swarm of 1989. Nature, 347, 376-378. http://dx.doi.org/10.1038/347376a0
Pulinets, S.A., Boyarchuk, K.A., Hegai, V.V., Kim, V.P. and Lomonosov, A.M. (2000) Quasielectrostatic
Model of Atmosphere-Theremosphere-Ionosphere Coupling. Advances in Space Research, 26, 1209-1218.
Yizengaw, E., Moldwin, M.B., Mebrahtu,
A., Damtie, B., Zesta, E., Valladares, C.E. and Doherty, P.H. (2011) Comparison of Storm Time Equatorial Ionospheric
Electrodynamics in the African and American Sectors. Journal
of Atmospheric and Solar-Terrestrial Physics,73,156-163. http://dx.doi.org/10.1016/j.jastp.2010.08.008
Burke, W.J.,
Gentile, L.C., Huang, C.Y., Valladares, C.E. and Su, S.Y. (2004) Longitudinal
Variability of Equatorial Plasma Bubbles Observed by DMSP and ROCSAT-1. Journal
of Geophysical Research, 109, A12301. http://dx.doi.org/10.1029/2004JA010583
