Recently discovered TLEs (Transient Luminous Events) such as red sprites and elves provided a great opportunity to revisit the electromagnetic waves in the lower ELF (Extremely Low Frequency) region known as the Schumann resonances (SR). The resonance behavior is afforded by the low attenuation experienced by electromagnetic waves in this frequency range. Since TLEs are caused by energetic lightning with abundant energy in this range, these so-called ELF transients can be analyzed on a global basis from single measurement stations. In particular, the geographical location and the vertical charge moment of the lightning flash may be determined remotely. In this chapter, we aim at providing readers with an overview of electromagnetic waves from lightning in the SR frequency band. Then we introduce the technique to determine the location and demonstrate the global mapping of lightning for different thresholds of charge moment change based on the ELF transient observations in Rhode Island, USA. Meteorological interpretations of the global maps are also provided. Furthermore the sprite-producing winter lightning activity is characterized in Hokuriku by using the ELF field site in Moshiri, Japan. The generation condition for winter sprites and their coupling to the tropospheric lightning and to the ionosphere are also presented.
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