Faceting?

With cool clear nights in still relatively early season, I'd have expected to see plenty of trip reports noting the development of faceting and depth hoar within the snowpack. I've reluctantly been out of the mountains for the last two weeks or so, so I haven't been able to put shovel nor skis to snow. I've been surprised at the lack of metamorphosis I've seen reported. Is it happening?

Did the rains right before the arrival of high pressure hydrate the snowpack into a brick that's taking its sweet time to facet? Are we growing the "hard depth hoar" that LaChappelle occasionally notes?

After writing the above, more surfing shows that there are some reports of faceting in the snowpack info exchange, perhaps below the crust. Anyone else seeing something similar?

Thanks!

In the one pit I've dug in the last couple of weeks, the snowpack was a frozen brick to the ground -- this was last sunday near Alpental. The snow near the ground was wet, loose rounds -- maybe 4" of 4 finger to fist. We didn't see any faceting, but we didn't break out the lens and really analyze the entire block. No failures on a tap test and shovel shear.

Glad you brought this subject up Trumpetsailor.
Like you I was wondering the same thing. Maybe like me it's to cold to tour to far from the mothership. I have been surprised at the amount of reports that HAVE been reported given the temps. My fears are staying warm if I have a mechanical failure or potential injury.

Marcus' pit is interesting because of the ground surface conditions, wet rounds with some body. When a cold snap hits it reminds me of the conditions that happen in Alaska, where the hard surface ice facets to sugar. But I did read on NWAC that there is potential for deep faceting. I'm curious how that condition creates itself in the super cold.
Is it because the gradient temps are warmer at depth because of the earth surface? A full explanation of that phenomena would be interesting.

has anyone taken any temp profile readings lately? I'd guess the temp gradient would be pretty text book right now due to our consistent weather the last few weeks.

It is surprising that we're not seeing the cold temps (and dry air) drive faceting at the ground, does anyone have a explanation? Our snowpack shouldn't be deep enough yet to prevent this...

I didn't take temps in that pit described above, but the snow near ground was pretty wet and the entire snowpack was very, very hard and dense.  My guess is the rain saturation, followed by very cold temps, has mostly taken that liquid water straight to ice and there's not a lot of room for the water vapor to move (at the moment).

Even very hard, dense snow usually has a large amount of air in the space between the crystal grains. Most of the water vapour in the snowpack is generated by sublimation anyway ( not melting ), so it doesn't matter if there's liquid water or not. Moisture transport in the snowpack is complicated, but generally speaking, moisture moves from the top of one crystal to the bottom of another.

Specifically, facets form because of various complicated rules about moisture/deposition on convex/concave surfaces on individual snow crystals, but the high growth rate is what creates the facets, and high growth occurs best when there is significant mass transport in the snowpack. Large temperature gradients move lots of moisture because water vapour travels from high concentration ( in the relatively warm snowpack ) to low concentration ( in the very cold atmosphere ).

For Joedabaker:

Depth hoar forms in the snowpack for the same reasons that large crystals form in the atmosphere:

1. Relatively warm temperatures ( close to the ground is relatively warm ).
2. The most moisture for crystal growth is found in the warmest areas ( warmer air holds more moisture than colder air ).
3. Depth hoar crystals have been growing for the longest time.