I have no idea why the script writers for the Wizard of Oz didn’t put those words into the mouth of the Wicked Witch of the West in this familiar scene. As she transitions straight from a green solid to a presumably noxious vapour, the Wicked Witch instead shrieks . . .
Pshaw. It’s a clear-cut case of sublimation. Not in this sense . . .
the act of expressing strong emotions or using energy
by doing an activity or creating something,
or the activity or work itself
but in this one . . .
Sublimation is the conversion between the solid
and the gaseous phases of matter,
with no intermediate liquid stage.
I checked the clip again to be sure. Yeah, no. No intermediate liquid stage — no wretched puddle of melted witch — so sublimation it was.
“How did we get here?” you ask. Maybe I’m sublimating something else into this blog post, but I think it’s as simple as our snow pack being down significantly this week (Calloo, callay!). As always, there is less melt-water on the streets than I’d expect, even allowing for the ten-to-one equivalence factor, snowfall to rainfall. And as our wind speeds this week approached 60 km/hr, I was reminded of a relatively recent learning — which, at my age, means something I picked up in the last 10 years or so — that windy days evaporate snow with no intermediate liquid stage required.
. . . in the western U.S.,
there’s a wind called the Chinook, or “snow eater,”
that vaporizes snow before it even has a chance to melt. . . .
The air is so dry that when it hits a snowpack,
the frozen water evaporates, going directly from the ice to vapor and bypassing the liquid phase entirely.
This is called sublimation,
and it’s a common way for snow to disappear in the arid West.
– Dave Thurlow of the Mount Washington Observatory
Well, if anyone had bothered to ask, I would have said that the Chinook (which I’ve never before heard called Snow Eater) was a quintessentially Calgary phenomenon, bringing its distinctive arch to the horizon, migraines to susceptible people, and respite from winter to everyone else. Now I know that it gets as good as it gives, taking snow vapour with it as it dances down the Foothills and out across the Prairies.
And although the humid East doesn’t get the arid West’s Chinooks, here also a sunny and windy day eats more snow than a sunny day all by itself.