sferics

noun[plural only]2

1. •
   Electromagnetic pulses caused by atmospheric phenomena, such as lightning. plural of sferic

   • A Sferics Locating System has been developed to determine the geographical location of lightning strokes... — 1920
2. •
   Radio interference caused by sferics; atmospherics.

   • In the identification of sources of short whistlers, the spectral characteristics of the sferics can often be used to establish many sferics as doubtful... — 1959