Sound is louder at night

Everything is louder at night. It’s not your imagination, it’s physics. The science is simple, sound likes to travel through cold air.

When the sun is up, the Earth’s surface is constantly being heated, which also warms the surrounding air. After being lightly toasted, the air closer to the ground becomes hotter than the air further away in the sky. To stay in this colder air, sound bends upward towards the sky, away from listening ears.

When the moon rises, something interesting happens, something called a temperature inversion. Because the Earth’s surface is not heated by the sun, the air closer to the ground gradually becomes colder than the air … in the air. So to try and stay with this now colder, lower air, sound bends downward towards the ground, where ears all around can listen.

That’s why noise is clearer, and louder at night; the sounds are travelling further. The effect is also amplified if a sound is moving over water. Now you know why everything is louder at night.