Modelling the diurnal evolution of the resonance spectral structure of theatmospheric noise background in the Pc 1 frequency range

We calculate the frequency spectrum of the electromagnetic background noise in frequency range 0.1-5 Hz based on the model attributing its formation t o the ionospheric resonant filtration of the radiation from distant lightni ng discharges (Belyaev, P.P., Polyakov, S.V., Rapoport, V.O., Trakhtengerts , V.Y., 1989. Theory of formation of the resonance spectral structure of at mospheric electromagnetic noise background in the range of short-period geo magnetic pulsations, Izvestiya vuzov-Radiofizika 32(7) 802-810). Characteri stics of the spectral resonance structure (SRS) formed due to the ionospher ic Alfven resonator are obtained and their dependence on ionospheric parame ters is considered; the SRS variation during a day is discussed. The calcul ations are compared with the ULF ground based observations at Sodankyla and Nizhny Novgorod; consistency of theory and experiment is demonstrated. Opp ortunities to use such data to determine some of ionosphere parameters are discussed. (C) 2000 Elsevier Science Ltd. All rights reserved.