Why Does South Dakota Snow Appear To Have A Blue Tint?
What is that picture? Is it a giant pile of shaving cream? Or could it be a big egg that is about to hatch an alien? OK, maybe I'm watching too many sci-fi movies.
It's actually a pile of snow in Sioux Falls that has buried a high-power white LED floodlight. The alien egg sound more fun though. But the question I had when I took the picture is how come the snow appears to be blue?
Have you ever noticed a blue tint in a pile of deep snow? I've lived in the snow belt pretty much my whole life and I've only just noticed this blue tint. At first, I thought I was seeing things but it really is there.
It turns out the reason for a blue tint in deep snow is the same reason that glaciers appear blue.
According to the USGS, "Glacier ice is blue because the red (long wavelengths) part of white light is absorbed by ice and the blue (short wavelengths) light is transmitted and scattered. The longer the path light travels in ice, the bluer it appears."
And according to NASA, that principle is the same reason the sky appears blue.
So the next time you are breaking your back shoveling deep snow, you will at least know why it has a blue tint.