ELF resonant cavities in the geospace as space weather indicators

1Koloskov, AV, 1Sinitsin, VG, 1Gerasimova, NN, 1Yampolski, Yu.M
1Institute of Radio Astronomy of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine
Kosm. nauka tehnol. 2008, 14 ;(5):049-064
Publication Language: Russian
Ground-based techniques for space weather monitoring rely on measurements of electric and/or magnetic field components in the ground signatures of wave processes in the geospace. The structural formations which can respond to variations of physical conditions in the magnetosphere (and thus become space weather indicators) are the resonant cavities for electromagnetic and MHD waves which exist owing to the non-uniform spatial distribution of the terrestrial plasma. The characteristic time periods shown by wave processes in these cavities fall into the range of ULF and ELF waves. We consider the frequency, amplitude and polarization parameters of the wave fields in the magnetospheric resonator, the ionospheric Alfven resonator and the cavity between the Earth and the ionosphere, varying under the impact of geomagnetic field disturbances and solar proton events. A theoretical model is developed for the coupling of Alfven wave resonators in the ionosphere and magnetosphere.
Keywords: geomagnetic field, resonators, solar proton events
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