- the speed of sound is greater in denser materials, so the velocity of sound is greater in fog than in normal air.
- distant noises mostly sound low and dull; nearer noises are higher and brighter
- fog carries sound more efficiently than dry air, so even the faintest noises drift for miles. You can never judge distance accurately from the noises you hear in fog because they will probably be distorted in some way.
- size can become distorted too; when visibility in fog is between 30 and 150 yards (about 25 to 140 m), vessels and other objects frequently appear twice their normal size. This illusion effectively doubles the speed of approach...
Shadows are cast through fog in three dimensions.
The fog is dense enough to be illuminated by light that passes through gaps i
n a structure, but thin enough to let a large quantity of that light pass through to illuminate points further on. As a result, object shadows appear as "beams" oriented in a direction parallel to the light source. These voluminous shadows are due to the same cause as crepuscular rays, which are the shadows of clouds, but in this case, they are the shadows of solid objects.
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