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

<p><strong>Figure 4.</strong> 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.</p> <p><strong>Abstract</strong></p> <p>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.</p>