There’s a scene in Harper Lee’s To Kill a Mockingbird — one of my all-time favorite novels — where the little girl-narrator, Scout, sees pretty white snow flakes falling and assumes the world is ending. She’s never seen snow before, since it’s a very rare occurrence in rural Alabama. The world didn’t end then, and it’s not ending now, but it’s just one more bit of evidence that weather is a very wacky thing.
Unless, like Scout, we’ve never experienced a genuine snowfall, we probably take snow a bit for granted. It’s just another form of precipitation, after all, and we have a pretty solid grasp of that particular cycle. Just for the record, snow is not frozen raindrops; that would be sleet. Under certain conditions, water vapor can condense directly into tiny ice crystals, skipping the raindrop phase altogether, and usually forming the shape of a hexagonal prism (two hexagonal “basal” faces and six rectangular “prism” faces).
To read the full, original article click on this link: Let It Snow: The Science of Snowflakes | Cocktail Party Physics, Scientific American Blog Network
