A sprite producing lightning discharge emits a particularly intense broadband radio signal up to ~130 kHz which was recorded on board the DEMETER spacecraft on 17 November 2006

Figure 4. A sprite producing lightning discharge emits a particularly intense broadband radio signal up to ~130 kHz which was recorded on board the DEMETER spacecraft on 17 November 2006.

Abstract

The acceleration of electrons results in observable electromagnetic waves which can be used for remote sensing. Here, we make use of ~4 Hz–66 MHz radio waves emitted by two consecutive intense positive lightning discharges to investigate their impact on the atmosphere above a thundercloud. It is found that the first positive lightning discharge initiates a sprite where electrons are accelerated during the exponential growth and branching of the sprite streamers. This preconditioned plasma above the thundercloud is subsequently exposed to a second positive lightning discharge associated with a bouncing-wave discharge. This discharge process causes a re-brightening of the existing sprite streamers above the thundercloud and initiates a subsequent relativistic electron beam.