16. The Role of Lightning in Global Communication
Surprisingly, lightning—often considered as a disruptive agent for communications—actually plays a vital part in preserving world radio communications. This is the result of a phenomena sometimes referred to as “sferics” or “radio atmospherics”.
Every lightning strike releases a wideband radiation surge. Travelling great distances, these radio waves bounce between the surface of Earth and the ionosphere—a layer of charged particles in the high atmosphere. This produces a natural waveguide enabling very low frequency (VLF) radio waves to spread around the planet.
Using this phenomena, the U.S. Navy and other agencies have established long-range communication systems. These VLF systems allow some degree of penetration of saltwater, therefore enabling subsurface communication without surface access.
Moreover, the ionosphere’s electrical characteristics are preserved in part by the continual background of radio noise produced by worldwide lightning activity. The ionosphere would progressively lose its capacity to reflect radio signals without this continuous electrical stimulation, hence perhaps upsetting long-distance radio communications.
Scientific study also makes advantage of radio waves produced by lightning. Scientists may follow world thunderstorm activity, analyse the Earth’s ionosphere and magnetosphere, and even probe the electrical characteristics of distant worlds by tracking these natural radio transmissions.
Fascinatingly, lightning on other worlds—including the massive storms on Jupiter—also generates radio transmissions. Analysing these alien lightning strikes offers important new perspectives on the atmospheric dynamics of other worlds inside our solar system.