ИСТИНА

According to recent studies, sprites and other mesospheric transient luminous events over thunderclouds are due to large cloud-to-ground (CG) flashes almost exclusively with positive polarity. It appears that a long-lasting intense continuing current in the parent positive lightning is necessary for the initiation of the sprites. The presence of the strong continuing current in sprite-associaeted lightning strokes can explain, in principle, the time lag of the sprite, which may delay from a few milliseconds to a few hundred milliseconds from the lightning discharge. Simultaneous optical and ELF electromagnetic observations are an effective trchnique for detecting sprite-associated events and for improvement of spatial, temporal resolution of both the sprites and parent CG lightning. In order for extracting sprite current and ELF magnetic variations is commonly modeled. In this report the main emphasis is on ELF power spectra of magnetic variations due to sprite-producing ligthning discharges, A teqnique of sprite parameters extracting based on lightning power spectrum is proposed.