 Poster: A snowHead
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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My understanding is the issue is the relative water content of the snow which is going to be determined by the extent of refreeze (a glacier is going to keep the snow very cold even if the air temps are warm). But if it doesn't refreeze over night on normal non glacial snow then as the sun warms the snow it will rapidly transform into wetter snow with a higher water content. This water creates the stickiness and after a certain it can have enough adhesion to literally stop you in your tracks. Take a look at your bases after you have been skiing in really sticky snow and look at the water pattern on your bases. You can offset it with the right wax to some degree. Or you can order a beer, sit on the terrace and get a suntan. 
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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You can offset it with the right wax to some degree. Or you can order a beer, sit on the terrace and get a suntan
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Thats really a tough choice though. 
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You need to Login to know who's really who.
You need to Login to know who's really who.
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It's mainly about the age of the snow being exposed to the warm temperatures, thus the structure of the snow and how this affects water content. The fresher the snow is, the stickier and slower it will be when exposed to warm temperatures and this is what happened on CairnGorm on Saturday, fresh snow having fallen overnight thawing for the first time (and getting rained on overnight).
As the snow ages in freeze/thaw cycles and becomes more granular it's less likely to get stick, true granular spring snow has a large crystal structure that has a lot of free space that allows water to drain freely through the snow pack. An effect of this in Scotland is that in rain or very warm temperatures the snow will actually get faster as melt water rounds off the snow crystals giving a ball bearing type effect.
Ironically thus over the coming days on CairnGorm as the thaw continues and last weeks accumulations melt out and snow depth reduces, surface conditions and thus the quality (though not quantity) of the skiing on offer will improve steadily.
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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Should have added to the above that in such conditions as found Yesterday, recently pisted or heavily skied terrain will be best. The more ski traffic on a run the more the water gets squeezed out, the snow structure breaks down and ages and it will gradually start to improve. Probably why the Cas and White Lady were reportedly much better than higher off piste stuff that would have been glue - I've skied up to the Summit up the Marquis Well's snowfield without skins in such conditions!
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You'll need to Register first of course.
You'll need to Register first of course.
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I always thought that snow that thawed refroze as ice, not different shaped snow crystals. When it does thaw, I have only ever known it form a crush on powder, not form ball bearing shaped snow crystals. When a thawed piste freezes over night and is pisted, the surface is corduroy ice.
The stickiness I have experienced has been purely down to water surface tension on too cold a base wax. I admit to only ever having had 2 days of wet sticky snow experience.
Is Scottish snow different or am I wrong?
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bar shaker, the way snow transforms or goes through metamorphosis is very dependent on the temperatures both of the snow pack and the air temperature. In spring this can become quite radical as the warmth of the spring sun shifts to freezing overnight. As it goes through the melt and refreeze process (assuming the latter happens at this time of year which is doesn't always depending on conditions and altitude) the shape of the snow crystals changes significantly. So that whilst as you say it does freeze, the snow that then unfreezes can be very different from that that fell (or was part of the snow pack) the day before. In general if it starts with nice dendrytic star shaped crystals then over time and the melt refreeze process they will tend to transform into much larger granular rounded crystals. In spring these crystals are often surrounded by quite a bit of liquid water. This liquid water means that during the refreeze the snow if very hard, but as soon as it melts when the sun comes out very soft and wet.
The impact of sun on a chilled beer on a terrace can also be quite bad and the refreeze of beer over night can really screw things up. This is why it is much better to drink the cold beer in the sun on the terrace really quite quickly...
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bar shaker, it refreezes as neve rather than ice unless it melted completely. Generally to get this it needs to have had quite a bit of sun/heat well past the point of being spring snow to what most people would call rotten snow or if on piste slush. When it's this wet you shouldn't be skiing it off piste anyway as it's dangerous and it screws up the spring snow as the deep tracks freeze solid in it. Anyway, overnight the rotten snow refreezes and becomes absolutely bulletproof then warms up to become spring snow again followed by overheating and rotten snow which has a massive water content.
I agree with your reason for slowing down in this snow: it's purely down to water tension between the ski/board and the wet top of the snow, in this case there is just too much water present on top of the snow. As well as using a warm temp wax and zardoz notwax having a deep structure ground into the base helps a hell of a lot as it enables more water to drain. As an aside I noticed the other day that a lot of the speed skiers had a deep channel down the middle of their skis which I thought might have something to do with this.
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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You can do an experiement to re-create the sticky effects of different moisture contents in your very own local public loo - assuming it has a hot air hand drier (a traditional one, not one of those trendy one like an airblade or xcelerator)
After your next visit wash your hands (!) and go to the hot air hand drier. Rub them constantly as you dry your hands. Whilst they are very wet, they remain slippery with little friction. Just before they dry completely they will start to stick together and there is much more friction as you rub them. Then finally when they are completely dry they become smooth and not sticky again.
der der
science in action in your local bogs.
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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Animal Pee. Marmots/Badgers/Deer etc.
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Gazzza, I understand hydrodynamics from a previous career in windsurfing and before that, club level slalom water skiing. Neither had anything to do with wet hands, but then I have never managed to achieve lamina flow when rubbing my hands under a hand dryer.
Swirly, That makes sense to me.
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You know it makes sense.
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| Swirly wrote: |
| . As an aside I noticed the other day that a lot of the speed skiers had a deep channel down the middle of their skis which I thought might have something to do with this. |
Until quite recently all skis had that channel. I seem to remember that it was supposed to help keep the ski running straight but they discovered it actually had little effect so dropped it. Perhaps enough effect to make a difference to speed skiers. (I doubt that water in the snowpack would have time to be pressed into the groove - though I'm prepared to be told I'm wrong.)
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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snowball,
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Poster: A snowHead
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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I can't remember how long ago it changed, actually: 15 years ago perhaps? A bit more? As I said, quite recent
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I've got a pair of '92 Salomons in the garage that have the groove down the middle of the base.
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FAQ
, but can somebody tell me why snow sometimes gets very sticky as it warms up 
. You have to remember I still have my 1958 skis stored away.
)