Random.org is a website that produces "true" random numbers based on atmospheric noise.

There are several Random.org radio listening stations that generate 3,000 bits per second from the atmospheric noise picked up.

The atmospheric noise depends on frequency, location and time of day and year.

Nothing came from the speaker but atmospheric noise and the repeated Mayday message.

The sum of all these lightning flashes results in atmospheric noise.

From 1960s to 1980s, a worldwide effort was made to measure the atmospheric noise and variations.

Random.org generates random numbers using atmospheric noises (see also Random.org).

It was too loud to be atmospheric noise, random though it might have sounded.

Works best in winter due to atmospheric noise in summer.

Then on the third track, you hear dim, compressed atmospheric noise - from a night street?