|Original Art and Story (c) by Sandra Russell|
A good friend of mine takes hundreds of color photos of flowers every year. She has an abundant series of garden beds with gorgeous combinations of colors planted. A few days ago she took a lovely photo of some frozen apricot flower (I can't recall the name) against a background of sage green leaves and deep violet multi-bloomed stalks of flowers; a stunning image. All in the foreground was covered in tiny hairs or beads of ice which she called hoar frost. Well, as a kid I read a story in my grandma’s attic library about "Jack Frost" and his army of frost fairies who came along in Autumn to touch the leaves and change nearly all the greens to oranges, purples, reds and gold...I don't remember how the story went entirely and have been searching to find it again. I have a couple of strong leads including as I found yesterday a huge controversy about one “King Winter” with variations; authored by Helen Keller/Annie Sullivan. Who knew? Anyhow, today I learned that 'hoar frost' is also sometimes confused with 'rime frost' and I learned the difference.
Rime ice often happens in areas of dense fog. It is when supercooled water drops (in liquid form) in the air come in contact with a surface below freezing. Those liquid water droplets then freeze on contact. When very wet atmosphere touches a very cold metal mailbox for example, rime ice may form on contact. Hoar frost is similar to dew and happens on cold and clear nights. This is when water vapor as a gas, not a liquid form freezes onto a below-freezing surface skipping the liquid stage. I guess I can understand the difference here a little bit? If you see frost on a foggy night or morning, it's likely to be 'rime ice’ or ‘rime frost.’ If you see it on a clear dry atmosphere, then it's ‘hoar frost’? However, it you look at the photos available for images of both of these types of frost, they can sometimes look pretty much the same. I will say though that rime ice images tend to show sharp longer spikey formations with hoar frost looking a bit more like pave diamonds, crusted low surfaces of clinging frost. I think I prefer to think of that pesky ‘Jack Frost’ and imagine him fencing with an icicle for a sword at a stubborn oak leaf not willing to give up his green coat for gold... Maybe for more delicate jobs he uses a paintbrush and turns the berries on the bushes to scarlet. Oh and stirring in the wind the frost fairies tiptoe along even the evergreens coating them with diamond jackets of ice.