# Why does a rolling thunder always starts with a high pitch and ends with a deep, low sound? Tags: acoustics, atmospheric-science, lightning - Score: 11 - Views: 2157 - Answers: 2 - Answered: yes - Asked by: Deschele Schilder (1 rep) - Asked: 2016-06-03 - Edited: 2016-06-05 - Site: physics - Closed: closed ## Question Rolling thunders always come cracking in with a high frequency, and the sound grows more deep as the rolling advances, ending with the deep sound of a roaring lion. Why? This is not the same question than the one of the extended sound but about the way we hear the rolling thunder from the beginning till the end. The sound starts with a higher frequency than that with which it ends and I was wondering why. ## Answers ### Answer by Han-Kwang Nienhuys (score: 2 [ACCEPTED]) Higher frequencies are attenuated (absorbed) more strongly than lower frequencies. Here are a couple of attenuation values from this table of sound-wave attenuation (90% relative humidity): f (kHz) a (dB/km) 1 5.3 2 9 4 20 8 63 The discharge itself will generate a wide spectrum of frequencies, from infrasonic all the way to ultrasonic. Your ear is much more sensitive to high frequencies (1 kH