Sferic

sferic [sfe-rik] (sfîrˌ◌ĭk, sfĕrˌ◌-).
noun

1. “A radio atmospheric signal or sferic - an electromagnetic impulse caused by natural atmospheric interference; i.e. a short burst VLF radio emission produced by lightning. Sferics or ‘spherics’ can be received thousands of kilometres from their source.”

2. “Also spherics (used with a singular verb) the study of atmospherics.”