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Basic experimental results .

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Basic experimental results .

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  1. International symposium on monitoring and prediction of Earth’s environment by using electromagnetic methodsMay 27, 2013, The University of Electro-Communications, Chofu, Tokyo, JapanGeneration and scattering of the VHF electromagnetic radiation by seismic related electric discharges in the troposphere.V.M. Sorokin Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, Russian Academy of Sciences (IZMIRAN), 142190 Troitsk, Moscow , Russian Federation • This report presents the theory of generation of electromagnetic radiation and VHF electromagnetic wave scattering by random electrical discharges in the lower atmosphere. Discharges arise in turbulent atmosphere at strong DC electric field connected with growing seismic activity. The theoretical results are confirmed by observation data.

  2. Basic experimental results. Seismic related quasi-static electric field in the atmosphere – ionosphere circuit. • Enhancement of seismic activity and typhoons produce DC electric field disturbances of the order of 10 mV/m in the ionosphere. • These ionospheric disturbances occupy the region of the order of several hundred km in diameter over epicenter. • DC electric field enhancement arises in the ionosphere from hours to 10 days before earthquakes. Chmyrev et al., Phys. Earth Planet. Inter. 1989. Sorokin et al., Journ. Atmos. Sol.-Terr. Phys. 2005. Gousheva et al., Nat.Haz.Earth Syst.Sci., 2008. Gousheva et al., Nat.Haz.Earth Syst.Sci., 2009. • DC electric field on the Earth surface in epicenter area does not exceed the background value ~100 V/m. Vershinin et al., Atm. Ionosp. Elect.-Magn. Phenom., 1999

  3. VHF radiation of the troposphere disturbed region located over seismic zone. VHF radiation is generated at the altitudes 1 – 10 km in the atmosphere over the epicenter of Eqs. Ruzhin et al., Geophysical Res, 1999. Permanent monitoring of the electromagnetic VHF radiation for three-year period in Greece shows that the generation region is located at altitudes (1 – 10) km in the atmosphere above the epicenter of an EQ area. The radiation is observed during several days before an EQ. Enhancement of the DC electric field up to the value of the order of 10 mV/m in the ionosphere is observed by the satellite during the same period. The occurrence of such a strong DC electric field in the ionosphere is related to the electric current flowing into the atmosphere – ionosphere circuit.

  4. The region of generation of VHF electromagnetic radiation is at the altitudes of the order of several kilometers above EQ epicenters located behind the horizon.VHF radiations are found to have occurred for several days before an EQ. Their duration reaches several days. If VHF electromagnetic radiation is propagated on the distance more than a wave length, the condition of optical propagation is fulfilled. Consequently, it is possible to receive the signal at distance of the order of 300 km just in the case if its source is located in the atmosphere above Earth’s surface. Ruzhin and Nomicos (2007)

  5. Over horizon propagation of the VHF transmitter signal. Kushida & Kushida (1998, 2002) introduced an empirical earth­quake prediction method based on monitoring anomalous VHF-band radio waves transmitted from an FM radio station beyond the line of sight. Sakai el al.(2001) showed that anomalous propagation of VHF-band radio waves emitted from a broadcasting station in Sendai City were related to earthquakes with magnitude greater than 5 that occurred in the area between Sendai and the Tateyama observatory in Chiba Prefecture. Fukumoto et al.(2002) confirmed that the anomalous propagation events were the result of scattering of VHF-band radio waves immediately prior to earthquakes, by documenting reception at an observatory that was beyond the line of sight of transmission location. Pilipenko et al. (2001) showed that the received intensities of scattered waves were stronger when the antenna was at a shallower angle, which implied that the scattering body was in the middle atmosphere rather than in the ionosphere. Fujiwara et al.(2004) also reached the same conclusion using a more rigorous method, and recorded no scattered waves when antennae were oriented vertically. Hayakawa et al.(2007) described a generation mechanism of atmospheric disturbances resulting from changes in geochemical quantities associated with earthquakes and VHF radio wave refraction. Yonaiguchi el al.(2007) discussed that the effect of long-range VHF wave propagation is usually due to meteorological radio ducting. Moriya et al., (2010) have observed the anomalous VHF-band radio-wave propagation beyond the line of sight prior to earthquakes. Radio waves transmitted from a given FM radio station are considered to be scattered, such that they could be received by an observation station beyond the line of sight.

  6. Schema of the over horizon transmitter wave propagation due to scattering one on electric discharges in the troposphere. • 1. Transmitter. 2. Receiver. 3. Disturbed region of troposphere with electric discharges. 4. Line of sight. 5. Incident wave. 6. Scattered wave.

  7. This theory is based on the model for atmosphere – ionosphere electrodynamic coupling. According to this model DC electric field is generated by seismic related Electro Motive Force (EMF) in the lower atmosphere. Inclusion of EMF into the atmosphere – ionosphere electric circuit leads to DC electric field growth up to 10 mV/m in the lower ionosphere. [Sorokin et al., 2001; 2005; 2007; Sorokin and Chmyrev 2010] 1. Earth surface 2. Conductive layer of the ionosphere 3. External electric current in the lower atmosphere 4. Conductivity electric current in the atmosphere – ionosphere circuit 5. DC electric field in the ionosphere 6. Field - aligned electric current 7. Charged aerosols injected into the atmosphere by soil gases Electric field in the ionosphere

  8. The ionization-recombination processes Equilibrium values of ion number densities are determined by the recombination process and the adhesion to aerosols in the atmosphere. The light single-charged ions and the heavy ions are produced as a result of light ions adhesion to aerosols in the atmosphere near the Earth’s surface. [Sorokin et al., 2007] EMF electric current and charge densities:

  9. Spatial distribution of external current, atmospheric conductivity, aerosols and DC electric field in the convective atmosphere is described bythe self-consistent set of nonlinear equations[Sorokin et al., 2007]:

  10. Input parameters of model are the atmosphere turbulence and convection, atmosphere radioactivity and aerosols density near the ground. A source of ionization defines the conductivity in the near ground atmospheric layer Radioactive elements such as radon, radium, thorium, actinium and their decay products enter the atmosphere together with soil gas. [Sorokin et al., 2001; Sorokin et al., 2007] The vertical distribution of ion production rate is a result of atmospheric absorption of gamma radiation and alpha particles from the decay of radioactive elements being constituents of the atmospheric radioactivity. Curves 1,2 and 3 correspond to different levels of atmospheric radioactivity growing from 1 to 3.

  11. Calculation result of the altitude dependences of external electric current and atmospheric conductivity at the epicenter of disturbed region at different levels of atmospheric radioactivity. Sorokin et al., Natural Hazards Earth System Sci. 2007. • External current is formed as a result of: • convective transfer of charged aerosols, • ionization of lower atmosphere by radioactive sources, • adhesion of electrons to molecules, • interaction of charged ions with charged aerosols

  12. DC electric field related to current in the atmosphere – ionosphere electric circuit. Sorokin et al., J. Atmos. Solar-Terr. Phys. 2005. The equations for calculation of the horizontal components of electric field in the ionosphere have a form: The vertical component of electric field in the atmosphere – ionosphere layer is derived from the equation:

  13. An examples of large magnitude DC electric field distribution in the lower atmosphere normalized to the breakdown electric field [Sorokin et al., 2011] At definite conditions the seismic related DC electric field can reach the breakdown value in some region of the atmosphere (marked out by red in the figure below).

  14. Fluctuations of the atmosphere density and DC electric field reaching the breakdown value in turbulent vortices result in the formation of random electrical discharges in the disturbed region

  15. Generation of VHF radio emissions in the atmosphere Coordinates used for the calculation of characteristics of electromagnetic radiation. Maxwell equations

  16. Frequency spectrum of the electromagnetic radiation generated by random electric discharges. Green function Power spectrum of the electromagnetic radiation of discharges, which is observed during an interval of time T, is defined by the formula: The frequency spectrum of electric field of radiation is defined by the power spectrum:

  17. Discharge is the infinitely thin pulse linear current. Their spatial temporal distribution is chosen in the form: The model of distribution of linear current in a discharge is chosen in the form: Iudin and Trakhtengerts, Radiophysics and Quantum Electronics, 2001. is the square of cross-section of discharge. is the length of discharge. is the velocity of current wave in the discharge.

  18. The spectrum of electric field of radiation at a distance from the epicenter of disturbed region of the atmosphere is the mean-square value of linear current amplitudes of discharges in the cells, is the amplitude of linear current of discharge in the cell with number k. Spatial distribution of the probability density of discharges.

  19. Calculation result of the spectrum of electromagnetic radiation at distance 300 km from the epicenter of disturbed area. Radiation is formed by random discharges in the disk-like region. This region has radius 40 km and thickness 1 km. The centre of region is located at the altitude 6 km in the atmosphere. The vertical sections of line are denoted the experimental data.

  20. Calculation result of the spatial distribution of amplitude of the electromagnetic radiation at a frequency 50 MHz.Radiation is formed by random discharges in the disk-like region.The centre of region is located at the altitude 6 km in the atmosphere.

  21. Theory for scattering of transmitter wave on the random electric discharges. Coordinates used for the calculation Discharge is the vertical segment of conducting channel. The current density is formed as a result of charge polarization in the conducting channels by electric field of incident wave. Incident monochromatic wave is radiated by transmitter. Scattered electromagnetic field

  22. Spatial distribution of the mean value of electromagnetic radiation scattered by the conducting channels of random electric discharges Scattered electric field Green function:

  23. Calculation results of the over horizon spatial distribution of mean value of scattered electric field. The transmitter monochromatic wave is scattered on the random electric discharges. These discharges are occurred in the region of troposphere in which electric field reaches breakdown value. Axially symmetric scattering region Ellipsoidal scattering region 100km X 100km 100km X 600km

  24. Scheme of registration of VHF signals on the satellite. • Transmitter, • Receiver, • Satellite, • Direct signal, • Scattered signal, • 6. Electric discharges. VHF observations onboard the satellite could be an effective tool for detection and locating the seismically modified atmospheric regions of anomalously strong (breakdown) DC electric field. It could be reached through simultaneous registration of broad band VHF radiation from the ‘discharge’ region and electromagnetic waves from the ground VHF transmitters, both direct and scattered signals. Using of the direction finding technique with highly sensitive onboard VHF receivers could allow to locate the source of emission and scattering in the atmosphere and therefore to make applicable an additional type of the precursor signals in space.

  25. Pre-earthquake DC electric field reaching the breakdown value initiates numerous chaotic electrical discharges and related phenomena in the lower atmosphere • Chaotic electrical discharges. • Heating of atmosphere in the discharge region and the generation of outgoing long wave (8-12 μm) radiation. • Broadband electromagnetic VHF emission observable on the ground and in space. • Airglow in visible range of wavelengths. • Refraction and scattering of VHF radio waves in the troposphere providing the reception of VHF transmitter signals by over-horizon ground-based receivers and by satellites. • Growth of ozone concentration in the disturbed region.

  26. Atmosphere Above Japan Heated Rapidly Before M9 Earthquake (http://www.technologyreview.com/blog/arxiv/26773/)Infrared emissions above the epicenter increased dramatically in the days before the earthquake in Japan (D. Ouzounov et al., 2011)

  27. Conclusion DC electric field of conducting current flowing between the atmosphere and ionosphere can reach the breakdown value in the lower atmosphere over seismic area. The current source is an electromotive force in the ground-air layer caused by vertical transport and gravitational fall-out of charged aerosols injected by soil gases in the atmosphere during seismic activity. The region in which electric field reaches breakdown value is located at the altitudes from 1 to 10 km. Electric field forms the random electric discharges in this region of the atmosphere which are the source of VHF electromagnetic radiation. Over horizon propagation of the VHF transmitter signal is realized by scattering of this signal to the random electric discharges over seismic region. Calculation results are confirmed by observation data.

  28. Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, Russian Academy of Sciences (IZMIRAN) Brief information IZMIRAN, Kaluzhskoe Hwy 4, Troitsk, Moscow, 142190, Russian Federation http://www.izmiran.ru

  29. IZMIRAN is located in the new area of Moscow. • The Institute of Terrestrial Magnetism, Ionosphere and Radio Wave propagation deals with • solar and terrestrial physics, • physics of the solar-terrestrial relations, • cosmic rays, • physics of the ionosphere and magnetosphere, • the ionosphere and magnetosphere radio wave propagation, • the magnetism of the Earth and planets of the solar system.

  30. Scientific research departments Magnetism of the Earth and Planets Ionosphere and Radio Wave Propagation Solar-Terrestrial Physics Information and Computing Center Geophysical Forecasting Center Space Information Technologies Center Theoretical Dept. Education center A distinctive feature of IZMIRAN research is a desire to stage multi-disciplined investigations, using ground, aircraft, balloon, rocket and satellite methods.

  31. Center for Space Information Technologies The Center offers integrated solutions for the design, testing and exploitation of the onboard information complexes for spacecrafts as well as information support for space-based experiments of different nature. Center for Space Information Technologies was created in 1999 with the aim of providing information support for various space projects.

  32. CORONAS stands for "Complex Orbital Near-Earth Observations of the Solar Activity" (in Russian). The three stages of the Project were named  CORONAS-I, CORONAS-F and PHOTON. CORONAS is an international project with participants from Russia, Ukraine, Poland, Slovakia, Bulgaria, Germany, USA and France. The coordination of all activity within the framework of CORONAS project is carried out by IZMIRAN. The first of the three satellites, CORONAS-I, was successfully launched on March 2, 1994. The second spacecraft, CORONAS-F, was launched on July 31, 2001. CORONAS satellites are placed into the polar orbits with an altitude of about 500 km and inclination about 83 degrees.

  33. The CORONAS-I spacecraft • Among the principal scientific objectives of the project are • the study of energy transport from the solar interior to the surface; • the study of major dynamic phenomena of the active Sun (sunspots, flares, plasma ejections); • the study of cosmic rays accelerated in solar flares; • seismological studies of the solar interior based on observed global oscillations;

  34. Current space projects ISS International Space Station Jan 30, 2009 : Successful launch of the "CORONAS-PHOTON" spacecraft Space projects in stage B INTERHELIOPROBE Resonance Moon-glob Seismoprognos Space projects in Stage A PEP Polar Ecliptic Patrol IONOSAT Ionospheric Studies IZMIRAN participated in more than 25 completed space projects.

  35. Technical data of “COMPASS-2” SC Micro-satellite “Compass” was developed and produced by SRC “Makeyev Design Bureau” in cooperation with IZMIRAN. The first launch was in December 2001, the second launch was in 2006. Satellite mass (scientific equipment), 80(20) kg Volume for equipment, 67 dm3 Average orbit power consumption , 25 W Attitude control accuracy, 1 angular min S/C mission lifetime – 3 years (at least) Orbit parameters: - altitude, 500 km - inclination, 79 deg

  36. The Laboratory of Electromagnetic Field Theoryis included in Ionosphere and Radio Wave Propagation department Main direction of the works Electrodynamics of the ionosphere and the atmosphere. Electromagnetic and plasma response to the influence of different origins to the ionosphere. MHD waves in the ionosphere. Generation and propagation of the ULF/ELF electromagnetic waves in the ionosphere – magnetosphere plasma. Interaction of waves and particles in the ionosphere – magnetosphere plasma.

  37. Certain basic results:A theory of new type instability of acoustic gravity waves by electric field in the ionospheric plasma.  First satellite observation of and theoretical interpretation of the electron density fluctuations in the ionosphere over seismic region.A theory of generation of the short period geomagnetic pulsations related to absorption of solar flier X- radiation in the ionosphere.A mechanism of the acoustic gravity waves modification by magnetic field in the ionosphere.A theory of slow magneto hydrodynamic waves in the ionospheric plasma.First observation of and theoretical interpretation of the magneto ionospheric wave disturbances.A theory of gyrotropic waves in the ionospheric plasma.First satellite observation of and theoretical interpretation of the DC electric field formation and electron density fluctuations in the ionosphere over typhoon zone. A mechanism of the generation of narrow bend geomagnetic pulsation related to rocket flying observed on the Earth surface.   A theory of formation of the lower ionosphere disturbances by atmospheric electric current flowing into the ionosphere.A mechanism of the relative amplification of DC electric field in the ionosphere above seismic region as a result of external current formation in the lower atmosphere.The electrodynamic model of atmosphere – ionosphere coupling and its application to the investigation of plasma and electromagnetic effects related to natural and artificial disasters.

  38. Comprehensive study of a nature of the electrodynamic atmosphere-ionosphere interaction was carried out in the laboratory. An analysis shown that the single reason for the atmosphere-ionosphere electrodynamic coupling is the electromotive force (EMF) formed on the lithosphere-atmosphere boundary.

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