Satellite monitoring of anomalous effects in the ionosphere probably related to strong earthquakes

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Abstract. To prove a direct relationship between the quasi-static electric field disturbances and seismic activity is a difficult, but actual task of the modern ionosphere physics. This paper presents new results on the processing and analysis of the quasi-static electric field in the upper ionosphere (h=800-900 km) observed from the satellite INTERCOSMOS-BULGARIA-1300 over earthquakes' source regions (seismic data of World Data Center, Denver, Colorado, USA). Present research focuses on three main areas (i) development of methodology of satellite and seismic data selecting, (ii) data processing and observations of the quasi-static electric field (iii) study and accumulation of statistics of possible connection between anomalous vertical electric fields penetrating from the earthquake zone into the ionosphere, and seismic activity. The most appropriate data (for satellite orbits above sources of forthcoming or just happened seismic events) have been selected from more than 250 investigated cases.The increase of about 5-10-15 mV/m in the vertical component of the quasi-static electric field observed by INTERCOSMOS-BULGARIA-1300 during seismic activity over Southern Ocean, Greenland Sea, South-Weat Pacific Ocean, Indian Ocean, Central America, South-East Pacific Ocean, Malay Archipelago regions are presented. These anomalies, as phenomena accompanying the seismogenic process, can be considered eventually as possible pre-, co-(coeval to) and post-earthquake effects in the ionosphere.

Section: Low and Near -Equatorial Latitudessupporting

confidence: 81%

Section: Introductionmentioning

confidence: 99%

Quasi-static electric fields phenomena in the ionosphere associated with pre- and post earthquake effects

Gousheva

Danov

Hristov

et al. 2008

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“…Further development of this model includes a new method for computation of the electric field in the atmosphere and the ionosphere over active faults for arbitrary spatial distribution of external current in oblique magnetic field (Sorokin et al, 2005(Sorokin et al, , 2006. In our previous papers (Gousheva et al, 2005a, b;2006a, b, 2007, 2008a on the basis of INTERCOSMOS-BULGARIA-1300 satellite data we found arguments for seismically-induced increases in the vertical components of the quasi-static electric field up to 2-10-15 mV/m in the near equatorial, low, middle and high latitude ionosphere. In this paper we present supplementary data about quasi-static electric field anomalies according INTERCOSMOS-BULGARIA-1300 satellite information over the Southern Atlantic Ocean, Tonga-New Hebrides region, Northern Islands of New Zealand, Indonesian region, Eastern Canada, Labrador Sea, Caribbean region, Central America, Western coast of South America, South-West Pacific Ocean, Kuril Islands, Aleutian Islands, Southern Pacific Ocean, Southern Iran during seismic events in AugustSeptember 1981.…”

Section: Introductionmentioning

confidence: 99%

Ionospheric quasi-static electric field anomalies during seismic activity in August–September 1981

Gousheva

Danov

Hristov

et al. 2009

Self Cite

Abstract. The paper proposes new results, analyses and information for the plate tectonic situation in the processing of INTERCOSMOS-BULGARIA-1300 satellite data about anomalies of the quasi-static electric field in the upper ionosphere over activated earthquake source regions at different latitudes. The earthquake catalogue is made on the basis of information from the United State Geological Survey (USGS) website. The disturbances in ionospheric quasistatic electric fields are recorded by IESP-1 instrument aboard the INTERCOSMOS-BULGARIA-1300 satellite and they are compared with significant seismic events from the period 14 August-20 September 1981 in magnetically very quiet, quiet and medium quiet days. The main tectonic characteristics of the seismically activated territories are also taken in account. The main goal of the above research work is to enlarge the research of possible connections between anomalous vertical electric field penetrations into the ionosphere and the earthquake manifestations, also to propose tectonic arguments for the observed phenomena. The studies are represented in four main blocks: (i) previous studies of similar problems, (ii) selection of satellite, seismic and plate tectonic data, (iii) data processing with new specialized software and observations of the quasi-static electric field and (iiii) summary, comparison of new with previous results in our studies and conclusion. We establish the high informativity of the vertical component Ez of the quasi-static electric field in the upper ionosphere according observations by INTERCOSMOS-BULGARIA-1300 that are placed above considerably activated earthquake sources. This component shows an increase of about 2-10 mV/m above sources, situCorrespondence to: M. Gousheva (gousheva@space.bas.bg) ated on mobile structures of the plates. The paper discusses the observed effects. It is represented also a statistical study of ionospheric effects 5-15 days before and 5-15 days after the earthquakes with magnitude M 4.8-7.9.

“…Using the GPS TEC map, they also found that these anomalies moved from the equatorial northern crest towards the equator a few days before the earthquake. Satellite-based measurements were also investigated before earthquakes (Trigunait et al, 2004;Gousheva et al, 2006;Sarkar et al, 2007;Hsiao et al, 2009;Akhoondzadeh et al, 2010). Gousheva et al (2006) examined the ion density and quasi-electric field data onboard the INTERCOSMOS-BULGARIA-1300 satellite and found disturbances in both measurements a few minutes before some of the strong earthquakes.…”

Section: Introductionmentioning

confidence: 99%

“…Satellite-based measurements were also investigated before earthquakes (Trigunait et al, 2004;Gousheva et al, 2006;Sarkar et al, 2007;Hsiao et al, 2009;Akhoondzadeh et al, 2010). Gousheva et al (2006) examined the ion density and quasi-electric field data onboard the INTERCOSMOS-BULGARIA-1300 satellite and found disturbances in both measurements a few minutes before some of the strong earthquakes. Using DEMETER satellite measurements near the epicenters of three strong mid-latitude earthquakes, Sarkar et al (2007) reported significant fluctuations in the electron and ion density data a few days before the events.…”

Section: Introductionmentioning

confidence: 99%

Ionospheric variations before some large earthquakes over Sumatra

Hasbi

Ali

Misran

2011

Abstract. The paper investigates the ionospheric variations before some large earthquakes that occurred during [2004][2005][2006][2007] in Sumatra using GPS and CHAMP data. The TEC shows the occurrence of positive and negative anomalies detected within a few hours to 6 days before the earthquakes. These anomalies mostly occur during the daytime hours between 4 and 17 LT. The TEC anomalies are mostly consistent with the CHAMP satellite electron density data. The electron density analysis over the 28 March 2005 earthquake epicenter shows that an equatorial anomaly modification took place a few days before the event. The modification took shape in the form of crest amplification during the daytime. The comparison between the TEC and electron density measurements during very quiet geomagnetic conditions is shown to be a useful indicator of a forthcoming earthquake.