[La mission DEMETER, investigations récentes sur dʼeffets ionosphériques associés à lʼactivité de lʼhomme, et à lʼactivité sismique]
Deux des principaux objectifs scientifiques de la mission DEMETER, concernaient la recherche dʼeffets ionosphériques associés à lʼactivité sismique et lʼétude des perturbations engendrées par lʼactivité humaine ou les phénomènes naturels tels les orages. Les données acquises depuis presque 6 ans en orbite ont fourni matière à des observations inédites et/ou à des progrès substantiels dans la compréhension de phénomènes déjà connus. Après une brève description de la charge utile et des modes de fonctionnement, nous donnons un aperçu de quelques résultats récents des travaux entrepris dans ces deux domaines. Les effets de lʼactivité humaine intéressent essentiellement les émissions radio-électriques et nous présentons plusieurs résultats concernant les émissions engendrées par les réseaux électriques et les perturbations de lʼionosphère par les émetteurs VLF de forte puissance. En ce qui concerne les perturbations dʼorigine sismique, nous présentons les études statistiques réalisées pour caractériser les ondes naturelles et permettre de distinguer dʼéventuels effets sismiques. Lʼune dʼentre elles a permis de mettre en évidence une diminution de lʼintensité des ondes naturelles dans le domaine ELF, entre 1 et 2 kHz, quelques heures avant les séismes.
Two of the main scientific objectives of the DEMETER mission concerned the search for ionospheric effects due to earthquakes and the study of disturbances associated with human activities or natural phenomena such as thunderstorms. The large data base gathered during nearly 6 years of in-orbit operation has lead to making new observations and/or to improving the understanding of several, already identified, phenomena. The main effects of human activities are observed in the field of radio-electric emissions and we present several results on the EM waves generated by power networks or associated with high power VLF transmitters. The search for ionospheric disturbances associated with earthquakes relies on thorough statistical studies to disentangle seismic effects from the variations induced by the physical processes that control the ionospheric plasma and natural emissions. Several studies are presented, and one of them has demonstrated a decrease of the ELF wave intensity in the frequency range between 1 and 2 kHz a few hours before the shock.
Mot clés : Ionosphère, Activité sismique, Onde naturelle et émissions artificielles
Tatsuo Onishi 1 ; Michel Parrot 2 ; Jean-Jacques Berthelier 1
@article{CRPHYS_2011__12_2_160_0,
author = {Tatsuo Onishi and Michel Parrot and Jean-Jacques Berthelier},
title = {The {DEMETER} mission, recent investigations on ionospheric effects associated with man-made activities and seismic phenomena},
journal = {Comptes Rendus. Physique},
pages = {160--170},
publisher = {Elsevier},
volume = {12},
number = {2},
year = {2011},
doi = {10.1016/j.crhy.2010.11.009},
language = {en},
}
TY - JOUR AU - Tatsuo Onishi AU - Michel Parrot AU - Jean-Jacques Berthelier TI - The DEMETER mission, recent investigations on ionospheric effects associated with man-made activities and seismic phenomena JO - Comptes Rendus. Physique PY - 2011 SP - 160 EP - 170 VL - 12 IS - 2 PB - Elsevier DO - 10.1016/j.crhy.2010.11.009 LA - en ID - CRPHYS_2011__12_2_160_0 ER -
%0 Journal Article %A Tatsuo Onishi %A Michel Parrot %A Jean-Jacques Berthelier %T The DEMETER mission, recent investigations on ionospheric effects associated with man-made activities and seismic phenomena %J Comptes Rendus. Physique %D 2011 %P 160-170 %V 12 %N 2 %I Elsevier %R 10.1016/j.crhy.2010.11.009 %G en %F CRPHYS_2011__12_2_160_0
Tatsuo Onishi; Michel Parrot; Jean-Jacques Berthelier. The DEMETER mission, recent investigations on ionospheric effects associated with man-made activities and seismic phenomena. Comptes Rendus. Physique, Volume 12 (2011) no. 2, pp. 160-170. doi : 10.1016/j.crhy.2010.11.009. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2010.11.009/
[1] Earthquakes in connection with electric and magnetic phenomena, Trans. Seismol. Soc. Japan, Volume 15 (1890), p. 135
[2] Ionospheric Precursors of Earthquakes, Springer, Hedelberg, New York, 2004
[3] Electro-magnetic earthquake bursts and critical rupture of peroxy bond networks in rocks, Tectonophysics, Volume 431 (2007) no. 1, pp. 33-47
[4] Stress-activated positive hole carries in rocks and the generation of pre-earthquake signals (M. Hayakawa, ed.), Electromagnetic Phenomena Associated with Earthquakes, Transworld Research Network, 2009, pp. 41-96 (Ch. 3)
[5] et al. The DEMETER microsatellite and ground segment, Planet. Space Sci., Volume 54 (2006) no. 5, pp. 413-427
[6] et al. ICE the electric field experiment on DEMETER, Planet. Space Sci., Volume 54 (2006) no. 5, pp. 456-471
[7] et al. The magnetic field experiment IMSC and its data processing onboard DEMETER: scientific objectives, description and first results, Planet. Space Sci., Volume 54 (2006) no. 5, pp. 441-455
[8] et al. The ISL langmuir probe experiment and its data processing onboard DEMETER: scientific objectives, description and first results, Planet. Space Sci., Volume 54 (2006) no. 5, pp. 472-486
[9] et al. IAP, the thermal plasma analyzer on DEMETER, Planet. Space Sci., Volume 54 (2006) no. 5, pp. 487-501
[10] et al. High-energy electron detection onboard DEMETER: the IDP spectrometer, description and first results on the inner belt, Planet. Space Sci., Volume 54 (2006) no. 5, pp. 502-511
[11] et al. The DEMETER science mission centre, Planet. Space Sci., Volume 54 (2006) no. 5, pp. 428-440
[12] et al. On the nonlinear triggering of VLF emissions by power line harmonic radiation, Ann. Geophys., Volume 17 (1999), pp. 79-94
[13] Power line harmonic radiation (J. Kultima, ed.), Some Aspects of ELF–VLF Emissions in Geophysical Research, Sodankylä Geophys. Obs. Publ., vol. 98, Oula Univ. Press, Sodankylä, Finland, 2005, pp. 53-84 http://www.sgo.fi/Publications/SGO/thesis/ManninenJyrki.pdf (available at)
[14] et al. Comparison of magnetospheric line radiation and power line harmonic radiation: a systematic survey using the DEMETER spacecraft, J. Geophys. Res., Volume 112 (2007), p. A04301 | DOI
[15] et al. Power line harmonic radiation: a systematic study using DEMETER spacecraft, Adv. Space Res., Volume 40 (2007), pp. 398-403
[16] et al. Power line harmonic radiation observed by satellite: properties and propagation through the ionosphere, J. Geophys. Res., Volume 113 (2008), p. A08317 | DOI
[17] et al. Penetration of lightning MF signals to the upper ionosphere over VLF ground-based transmitters, J. Geophys. Res., Volume 114 (2009), p. A12318 | DOI
[18] et al. Survey of magnetospheric line radiation events observed by the DEMETER spacecraft, J. Geophys. Res., Volume 114 (2009), p. A05203 | DOI
[19] et al. First in-situ observations of strong ionospheric perturbations generated by a powerful VLF ground-based transmitter, Geophys. Res. Lett., Volume 34 (2007), p. L11111 | DOI
[20] et al. Radiation belt electron precipitation due to VLF transmitters: Satellite observations, Geophys. Res. Lett., Volume 35 (2008), p. L09101 | DOI
[21] et al. Examples of unusual ionospheric observations made by the DEMETER satellite over seismic regions, Phys. Chem. Earth, Volume 31 (2006), pp. 486-495 | DOI
[22] Anomalous seismic phenomena: View from space (M. Hayakawa, ed.), Electromagnetic Phenomena Associated with Earthquakes, Transworld Research Network, 2009, pp. 205-233
[23] Electron and ion density variations before strong earthquakes (M > 6.0) using DEMETER and GPS data, Nat. Hazards Earth Syst. Sci., Volume 10 (2010), pp. 7-18
[24] Patterns of F2-layer variability, J. Atm. Solar Terr. Phys., Volume 63 (2001), pp. 1661-1680
[25] Simple model for post seismic ionospheric disturbances above an earthquake epicentre and along connecting magnetic field lines, Nat. Hazards Earth Syst. Sci., Volume 8 (2008), pp. 1341-1347
[26] et al. Spacecraft observations of electromagnetic perturbations connected with seismic activity, Geophys. Res. Lett., Volume 35 (2008), p. L05109 | DOI
[27] Atmospheric electricity coupling between earthquake regions and the ionosphere, J. Atm. Solar Terr. Phys., Volume 72 (2010) no. 5–6, pp. 376-381
[28] Synthetic description of VLF electric field spectra from the ICE experiment on DEMETER, automatic recognition and characterization of natural and man-made emissions, Notes du Pôle de Planétologie, Institut Pierre-Simon Laplace, June 2010 http://www.ipsl.fr/fr/Documentation/Les-publications-de-l-IPSL/
[29] et al. Global diagnostics of the ionospheric perturbations related to the seismic activity using the VLF radio signals collected on the DEMETER satellite, Nat. Hazards Earth Syst. Sci., Volume 6 (2006), pp. 745-753
[30] Ten cycles of solar and geomagnetic activity, Solar Phys., Volume 70 (1981), pp. 173-195
[31] A two-component solar cycle, Solar Phys., Volume 131 (1991), pp. 187-209
[32] et al. Seismoionospheric GPS total electron content anomalies observed before the 12 May 2008 Mw7.9 Wenchuan earthquake, J. Geophys. Res., Volume 114 (2009), p. A04320 | DOI
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