Why do sounds sound more intense and mysterious at night?

Question

Why do sounds sound more intense and mysterious at night?

Answer 1

'what you can't see, you imagine'

Answer 2

you rely on your auditory senses because of poor visibility.

Answer 3

Sound is a compression wave, formed by compressiobn and rarefaction of the air molecules.  Therefore, the more dense the air, the more intense the sound will be.

At night, there are two effects related to this: The air is colder, and more dense; but more importantly, it is more dense nearer the ground; so the sound waves tend to travel more readily in the horizontal direction (during the day; sound travels upward more than horizontally - somehting you will observe if you ever travel in a hot air balloon.

Therefore, the sound travels more readily in a horizontal direction at night; which anyone living or staying near the seaside will attest.

In addition, of course, there are less extraneous noises during the night. from machinery, taffic, etc.

Edit: Michel is also correct: another reason why sound seems different at night.  Michel explaibned why it SEEMS different, I explained why it SOUNDS different.

Answer 4

When you lose sensory perception in certain areas, your mind will make up for that by focusing more attention on the other senses.

So, when you cannot 'see', your brain focuses more attention towards your sense of hearing to make up for it.  Thus, you notice more sounds and they have a greater effect on your thoughts/emotions when it's dark.