“…In numerous but already classical papers, it was shown that the knowledge of a conductivity‐height profile for the two lower layers of the ionosphere, the D and E layers, allows proper reconstruction of the fundamental properties of the Schumann resonances [ Wait , 1960, 1970; Galejs , 1961, 1962, 1965, 1972; Jones , 1964, 1967; Chapman and Jones , 1964; Chapman et al , 1966; Bliokh et al , 1977; Greifinger and Greifinger , 1978, 1979; Tran and Polk , 1979; Sentman , 1983, 1990; Sentman and Fraser , 1991]. As the natural mechanism of the ELF field propagation in the global resonator is two‐dimensional, Madden and Thompson [1965] proposed a model in which the two‐dimensional telegraph equation was used. The computations in their study were performed by solving a two‐dimensional network that was the lumped circuit representation of the transmission‐surface equations.…”