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Resonances in the Earth-Ionosphere Cavity by A.P. Nickolaenko & M. Hayakawa (Kluwer 2002)

Course: Topics in Discharge Phenomena (Fall 2003). Resonances in the Earth-Ionosphere Cavity by A.P. Nickolaenko & M. Hayakawa (Kluwer 2002). Introduction. theme: e.m. resonance phenomena in the Earth-Ionosphere cavity

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Resonances in the Earth-Ionosphere Cavity by A.P. Nickolaenko & M. Hayakawa (Kluwer 2002)

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  1. Course: Topics in Discharge Phenomena (Fall 2003) Resonances in the Earth-Ionosphere Cavityby A.P. Nickolaenko & M. Hayakawa (Kluwer 2002)

  2. Introduction • theme: e.m. resonance phenomena in the Earth-Ionosphere cavity • tool for probing global thunderstorm activity and properties of lower ionosphere • focus primarily at Schumann resonance (SR; predicted by W.O. Schumann in 1952) at 8, 14, 20 Hz • Fundamental parameters of the Earth-Ionosphere cavity • conducting earth and ionosphere • lower 30 km of atmosphere as dielectric • sustaining e.m. waves at • very low frequency (VLF) band : 3 – 30 KHz • extremely low frequency (ELF) band : 3 – 30 Hz, with wavelength of ~40,000 km (4 Mm)

  3. Historical • N. Tesla (1893): first attempt to artificially excite e.m. waves in the E-I cavity • A.P. Popov (1895): first detection of natural e.m. radiation from thunderstorms • G. Marconi (1901): used spark transmitters to send and receive radio signals across the Atlantic • E.O. Schumann (1952): predicted e.m. waves from thunderstorm activity could excite global e.m. resonance, aka Schumann Resonance (SR) • Balser & Wagner (1960): first confirmation of the SR • SR researches were aimed at military application, e.g. in submarine communication; 1990s: interests renewed after the discovery of sprites and other TLEs; TLEs are sources of Q-burst band below 50-60 Hz and slow tails above 300 Hz (reading: Boccippio et al., Sprites, ELF transients and Positive Ground Strokes. Science, 269, 1088-1091,1995; Cummer, JASTP 2003) • Three major thunderstorm regions: equatorial Africa, America and Southeast Asia

  4. Global lightning distribution(Sep-Nov, 1999)

  5. Resonances in the E-I cavity by simple geometrical argument • Longitudinal resonance (SR); where the radius of Earth a is 6400 km • Transverse resonance; where the height of the E-I cavity h is taken as 75 km • The transverse resonance frequencies is two orders of magnitude higher than those of the SR. No mixing is possible.

  6. Characteristics of lower ionosphere Electron gyrofrequency (cyclotron freq): Plasma frequency: Conductivity: Siemens (Sm):

  7. Special foci of this book • Practical information on site selection, layout, antenna and receiver characteristics, and system calibration • Detailed formalism on Schumann resonance; for both uniform isotropic and non-uniform anisotropic E-I cavity • Effective/engineering models for lightning discharges • Parameterization of global thunderstorm activity and its usage in interpreting the seasonal and interannual modifications in the SR recordings • Statistical models of natural radio signals in the frequency and time domains • Techniques of signal processes; how to extract particular geophysical information from SR recordings

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