Poster: A snowHead
|
There have been a couple of references on snowRacers to firming up race courses in Meribel otherwise in really poor condition by mixing tons of salt with the snow. Permitting events to go ahead even if under much less than ideal conditions.
Now how does that work?????? When I were a lad, we put salt on snow and ice to melt the stuff. Can anyone please explain?
I'm baffled.
|
|
|
|
|
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
|
Not a clue, except that I thought it was a "different kind of salt" - which binds the crystals together to create a hard crust...
|
|
|
|
|
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?
|
kuwait_ian, it is true that if you put salt (shall we say sodium chloride in this example) on ice then the ice will melt and the salt will dissolve. However, this is not due to any kind of "heating", it's simply that the system is trying to attain a phase equilibrium - i.e the state in which solid salt and solid ice can exist in equilibrium with each other. For sodium chloride and ice that state occurs at -21 C. Hence the effect of adding the salt is to melt a bit of the ice but, more importantly I guess in this case, it is to achieve a rapid cooling effect by formation of this "freezing mixture", which will temporarily stabilise the bulk of the snow/ice and give them time to hold the races
|
|
|
|
|
You need to Login to know who's really who.
You need to Login to know who's really who.
|
|
|
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
|
An interesting article on course inspection here including
Quote: |
Hard Crust over Soft Snow
This type of condition occurs after a warm spell or rain, and one night of cold. Small controlled groups should be allowed to do a tip to tail slip, but the main inspection should be performed by side slipping outside the course. To get a look at the line, stop in each section, outside the course, and glide in on a railed edge to look at the line. When you are done with that section or gate, glide back out. If we don't follow the glide in and out method, we will scrape down through some of the crust. The first few racers will get by ok, but by the mid 30-50's holes will start to develop, and people will start pre-releasing from their bindings. In some cases salt or fertilizer will be applied to the surface 30-40 minutes prior to starting. No one should be allowed on the course during that period to allow the chemical to set up. If the hill was not groomed prior to the snow setting up, then we will have a mess on our hands, with lots of slipping and chemicals. |
Quote: |
Fresh Heavy Wet Snow
This is the most difficult situation to deal with in racing, and needs to be controlled by the race organizer and the TD to ensure proper course conditions. In some cases a light slip over the top of the snow by several experienced slippers followed by salt will work. |
So it seems no bashing is done after adding the chemical(s). Fertiliser is presumably more meadow-friendly
|
|
|
|
|
You'll need to Register first of course.
You'll need to Register first of course.
|
Alan is right. Two effects have to be considered: the transient effect (while a reaction is occurring) and the nature of the new equilibrium (when it is finished). Mixing ice/water with salt is an endothermic reaction, i.e. one that absorbs thermal energy, producing a cooling effect. As for the new equilibrium, a mixture is produced which will have a melting/freezing point as low as -21C (attained if the proportion of ice/snow/water and salt is exactly right).
With a piste, while there is a still a decent quantity of H2O, albeit in the from of slush, the predominant place from which thermal energy can be absorbed is the slush itself (rather than from the ground or the air) - so, it gets icier, at least temporarily. After a while, it will absorb heat from the surroundings and will not maintain the low temperature necessary to remain in the solid state. So the whole process is good for the racers but bad for the punters who follow the next day.
As for the roads, the idea is get to the salt on before snow settles or ice forms. The energy to fuel the endothermic reaction then comes from the road surface and the air and the freezing point is depressed so that no ice or snow can form/settle on the road. In colder countries than England the method is useless and they tend to grit instead.
|
|
|
|
|
|
laundryman, fine explanation - I can get my head round that. TVM
|
|
|
|
|
|
kuwait_ian wrote: |
There have been a couple of references on snowRacers to firming up race courses in Meribel otherwise in really poor condition by mixing tons of salt with the snow. |
It can't be good on an ecological level. I know the highways department in the Savoie are concerned about the effect snow had on the environment and are as sparing as they can be in its use, they are not even allowed to salt part of the road to my LSR.
|
|
|
|
|
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.
|
davidof, I'll accept the thicky baton if necessary but what's an LSR ?
So we know now how it works but the original refs indicated the salt was mixed with the snow, and all I've found since indicates it's just sprinkled on the top and left there. Anybody seen it done?
|
|
|
|
|
|
|
|
snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
|
|
|
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.
|
Lovely Snowy Retreat ?
|
|
|
|
|
|
Bernard Condon, Not confirmed yet until davidof responds. All I could come up with was Little Side Road - which fitted the context but isn't nearly as much fun as tomski01's answer...
|
|
|
|
|
You know it makes sense.
|
This salt stuff is all very well. Where's the pepper? And I wouldn't mind a bit of Tabasco.
|
|
|
|
|
Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
|
Quote: |
effect snow had on the environment
|
I have to nominate davidof as the new holder of the snowHeads Thicky Baton for that typo. OK with you, Bernard ?
|
|
|
|
|
Poster: A snowHead
|
|
|
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
|
kuwait_ian wrote: |
Quote: |
effect snow had on the environment
|
I have to nominate davidof as the new holder of the snowHeads Thicky Baton for that typo. OK with you, Bernard ? ;-) |
fair cop.
LSR - local ski resort although the other variants are perhaps better.
|
|
|
|
|
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?
|
Bernard Condon, I have no problem admitting to being intel (ectually) challenged, both in this area and particularly concerning all skiing matters .. however don't you think it takes a real plonker to accuse others or highlight others' incompetence ?
All in the best possible taste ... of course
|
|
|
|
|
You need to Login to know who's really who.
You need to Login to know who's really who.
|
Newbie50 Sorry! You can be a professor or a rocket scientist on this site - it DOESN'T matter!! I am a relative newbie like you and was ambushed with this baton I just asked how the 'Search' facility worked! - you have been forewarned so you are lucky. But be on thy guard, it's not a gift one likes to keep and davidof will be keen to pass on the charm as soon as possible.
|
|
|
|
|
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
|
Bernard Condon, No problem ! Thanks for the context, now makes sense. Unfortunately (?) I am neither related to Einstein nor blessed with the skill of teaching others; recall a few relays as a youngster but dropped the baton then as well.
I am 'en guarde'.
|
|
|
|
|
You'll need to Register first of course.
You'll need to Register first of course.
|
The idea of the thicky baton is new to the site. Somebody started a thread about it somewhere a few days back but it's kind of propagated around the forums. Anyone can nominate a new holder but the primary responsibility for getting rid of it rests with the snowHead with the sticky hand and claw like fingers.
|
|
|
|
|
|
There's no end to the possibilities. A weekly pedant prize, a troll trophy.... not sure what it would do for the forum's good natured atmosphere though!
|
|
|
|
|
|
Quote: |
don't you think it takes a real plonker to accuse others or highlight others' incompetence ?
|
as a one-time holder of said stick I reckon Newbie50 has the right idea. Hopefully it will go the way of my dropped £80 carbon fibre pole, lost in the deep poudre and never seen again
|
|
|
|
|
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.
|
laundryman, most people melt ice with salt in Toronto, and it works, so it's not just for pre ice forming.
|
|
|
|
|
|
Newbie50, If Albie Einstein or Charles Darwin were snowHeads and had posted the Theory of Relativity, or Evolution of Species on this site, they would both have been hit with the Thickie Baton. That boy from Kuwait is FAST on the SEND key!
|
|
|
|
|
snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
|
I was wondering whether to start a battleships style, 'Find-Alan's-skip-pole' game....
|
|
|
|
|
|