Thoughts on New snow on glaciers and year round snow

[smitchell333]

Interested to hear what folks here think on calling avy danger with new snow on glaciers and permanent snowfields.

[iskibc]

Well, since Colorado has no glaciers we don't have to worry about it.

In my experience I've found that lower snowfall amounts typically stick pretty well to existing snowfields. I've never gotten much movement. Haven't really skied anything over 8" or so of new on top of an existing snowfield. Usually the snowfield is wet from the moisture and sticks to the new snow fairly well. I would be curious as well to see what the scientific response is to this.

[AltaPowderDaze]

glaciers where? around here, it seems that most glaciers/snowfields are pretty consolidated, therefore no problem with old snow. interface and new snow would be where you may see problems. a light snowfall 2-8" may fall and bond well but the resulting temp gradients can create one or two layers to watch in the future. once a solid slab w/ some weight shows up, then you could see movement. i have little to no experience with real glaciers, so take all that with a grain of salt. others like leeL may have some good info for you. you could also try tele tips for a scientific response.

[FiveLarge]

I should consult some of the other avy books I have for some other thoughts, and see if they have specific sections that address this...but I was just looking at the Snowy Torrents book for September/October avy accidents...and while they appear rare with the quick glance, in all that I saw, old summer snow was the bed surface. In the avy/snowpack analysis section for one of those accidents, the authors present the question..."how long for the new snow to bond well with the old?" Of course, many factors....but the authors state, in the case of new snow and old summer snow, the answer is often closer to weeks instead of days for a really solid bond.