This Phenomenon Occurs Shortly Before A Lightning Strike

Above the cliff, the crackling of electric current could be heard in the air.
This phenomenon occurs shortly before a lightning strike, when static electricity builds up in the atmosphere.
Before a lightning strike, an intense electric field creates conditions for the accumulation of charge, which causes characteristic sounds and sometimes even visible effects such as a "glow" in the air.
This is a process related to changes in the electromagnetic field, which in turn are caused by changes in the workings of the Earth's core.