Why can you see through a large bottle of water or to the bottom of a deep swimming pool but not through a tropical rain storm or whiteout?

Answer 1

Light is funny stuff, isn't it? In looking through a bottle of water or a pool, there is one interface between the mediums. Light is passing through air and water to let you see what you see. Each transition light has to make between mediums creates interference called refraction. That makes trying to see something clearly through multiple transitions increasingly difficult. You can "see through" a single incidence, and without difficulty. Just as stated in the question, you can see through a large bottle of water. But look at a drinking straw in a glass of water. You can see it clearly, but it appears to be "bent" in the water. Refraction. And when multiple refractive transitions occur because the light is having to move many times between mediums to get to you (through air, through a drop, through air, through a drop, etc.), your ability to resolve an object is increasingly challenged. A larger and larger amount of the light is "rearranged" in heavier rain (and at increasing distance). In addition, a bit of reflection off each drop occurs. That light is scattered, and it is unavailable to you to help you see something. In a heavy rain, your visibility drops, and that's why. A whiteout is the term we assign to snow that is so thick that resolving images at a distance becomes impossible. All we see is white. There isn't too much light passing through the snow flakes. The many "faces" on the crystals of frozen water that make up the structure scatter the heck out of the light. The light goes every which way, and when there is a ton of snow falling, the light is "all around us" and there is plenty of it, but it is coming from everywhere and not from anything we wish to see, even if it is a short distance away. Recall that light comes to us from what we see, either because that thing generates the light or it reflects light from another source (or both). For instance, if the light reflected off a car in a parking lot has to travel through a lot of snow flakes to reach you as you gaze out the window of a building at that car, you won't be able to see it clearly. And if the snow if heavy enough and the car is far enough away (or a combination), you won't see it at all. Everything went white in the whiteout. The light you needed coming off the object you wished to view, its "image" as it were, went everywhere.