Special Issue: The 2004 Great Sumatra Earthquake and Tsunami
- Open Access
GPS detection of total electron content variations over Indonesia and Thailand following the 26 December 2004 earthquake
Earth, Planets and Space volume 58, pages159–165(2006)
We report the response of the ionosphere to the large earthquake that occurred in West Sumatra, Indonesia, at 0058 UT on December 26, 2004. We have analyzed Global Positioning System (GPS) data obtained at two sites in Sumatra and at three sites in Thailand to investigate total electron content (TEC) variations. Between 14 and 40 min after the earthquake, TEC enhancements of 1.6–6.9 TEC units (TECU) were observed at subionospheric points located 360–2000 km north of the epicenter. From the time delays of the observed TEC enhancements, we find that the TEC enhancements propagated northward from the epicenter. The time delays between the earthquake and rapid increases in TEC, which occurred near the epicenter, are consistent with the idea that acoustic waves generated by the earthquake propagated into the ionosphere at the speed of sound to cause the TEC variations. A small TEC enhancement of 0.6 TECU was observed south of the epicenter, while no TEC enhancements were seen east of the epicenter. From a model calculation, we find that this directivity of the TEC variations with respect to the azimuth from the epicenter could be caused partially by the directivity in the response of the electron density variation to the acoustic waves in the neutral atmosphere.
Afraimovich, E. L., N. P. Perevalova, A. V. Plotnikov, and A. M. Uralov, The shock-acoustic waves generated by earthquakes, Ann. Geophys., 3, 673–686, 2001.
Artru, J., T. Farges, and P. Lognonné, Acoustic waves generated from seismic surface waves: propagation properties determined from Doppler sounding observations and normal-mode modeling, Geophys. J. Int., 158, 1067–1077, 2004.
Blanc, E., Observations in the upper atmosphere of infrasonic waves from natural or artificial sources: A summary, Ann. Geophys., 19, 395–409, 1985.
Calais, E. and J. B. Minster, GPS detection of ionospheric perturbations following the January 17, 1994, Northridge earthquake, Geophys. Res. Lett., 22, 1045–1048, 1995.
Fukao, S., Y. Yamamoto, W. L. Oliver, T. Takami, M. D. Yamanaka, M. Yamamoto, T. Nakamura, and T. Tsuda, Middle and upper atmosphere radar observations of ionospheric horizontal gradients produced by gravity waves, J. Geophys. Res., 98, 9443–9451, 1993.
Heki, K. and J. Ping, Directivity and apparent velocity of the coseismic traveling ionospheric disturbances observed with a dense GPS array, Earth Planet. Sci. Lett., 236, 845–855, 2005.
Hines, C. O., Internal atmospheric gravity waves at ionospheric heights, Can. J. Phys., 38, 1441–1481, 1960.
Hooke, W. H., Ionospheric irregularities produced by internal atmospheric gravity waves, J. Atmos. Terr. Phys., 30, 795–823, 1968.
Igarashi, K., S. Kainuma, I. Nishimura, S. Okamoto, H. Kuroiwa, T. Tanaka, and T. Ogawa, Ionospheric and atmospheric disturbances around Japan caused by the eruption of Mount Pinatubo on 15 June 1991,J. Atmos. Terr. Phys., 56, 1227–1234, 1994.
Kanamori, H., J. Mori, and D. G. Harkrider, Excitation of atmospheric oscillations by volcanic eruptions, J. Geophys. Res., 99, 21,947–21,961, 1994.
Kirchengast, G., Elucidation of the physics of the gravity wave-TID relationship with the aid of theoretical simulations, J. Geophys. Res., 101, 13353–13368, 1996.
Lay, T., H. Kanamori, C. J. Ammon, M. Nettles, S. N. Ward, R. C. Aster, S. L. Beck, S. L. Bilek, M. R. Brudzinski, R. Butler, H. R. DeShon, G. Ekström, K. Satake, and S. Sipkin, The great Sumatra-Andaman earthquake of 26 December 2004, Science, 308, 1127–1133, 2005.
Ogawa, T., H. Kumagai, and K. Sinno, Ionospheric disturbances over Japan due to the 18 May 1980 eruption of Mount St. Helens, J. Atmos. Terr. Phys., 44, 863–868, 1982.
Olsen, N., T. J. Sabaka, and L. T. Clausen, Determination of the IGRF 2000 model, Earth Planet Space, 52, 1175–1182, 2000.
Park, J., K. Anderson, R. Aster, R. Butler, T. Lay, and D. Simpson, Global seismographic network records the great Sumatra-Andaman earthquake, EOS, 86, 57, 2005.
Picone, J. M., A. E. Hedin, D. P. Drob, and A. C. Aikin, NRLMSISE-00 empirical model of the atmosphere: Statistical comparisons and scientific issues, J. Geophys. Res., 107(A12), 1468, doi:10.1029/2002JA009430, 2002.
Saito, A., S. Fukao, S. Miyazaki, High resolution mapping of TEC perturbations with the GSI GPS network over Japan, Geophys. Res. Lett., 25, 3079–3082, 1998.
Tanaka, T., T. Ichinose, T. Okuzawa, T. Shibata, Y Sato, C. Nagasawa, and T. Ogawa, HF-Doppler observations of acoustic waves excited by the Urakawa-oki earthquake on 21 March 1982, J. Atmos. Terr. Phys., 46, 233–245, 1984.
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Otsuka, Y., Kotake, N., Tsugawa, T. et al. GPS detection of total electron content variations over Indonesia and Thailand following the 26 December 2004 earthquake. Earth Planet Sp 58, 159–165 (2006). https://doi.org/10.1186/BF03353373
- total electron content
- acoustic wave