 Poster: A snowHead
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do anybody know of any ski resorts in europe with plenty of south facing slopes, i know of chamonix, alp dhuez, crans montana and saalbach.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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Alpe d'Huez has probably the sunniest slopes I know, of the ones you've mentioned.
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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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St Anton
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You need to Login to know who's really who.
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La Rosiere
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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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compostcorner, why do you want to know? To avoid these resorts? But many of these named are big with plenty of shaded slopes too. You are hardly seeking out sunny slopes??
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You'll need to Register first of course.
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Cervinia.
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| peanuthead wrote: |
| compostcorner, why do you want to know? To avoid these resorts? But many of these named are big with plenty of shaded slopes too. You are hardly seeking out sunny slopes?? |
Maybe he like to ski in the sum or is looking out for places with potential for good spring snow?
Anyway Samnaun is mainly south facing.
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Les Menuires has most of its skiing on south-facing slopes, and plenty of links to the rest of the three valleys for when south-facing slopes are not what you want.
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You'll get to see more forums and be part of the best ski club on the net.
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The Obertauernrunde actually directs you around either so you are facing the sun (assuming it is shining of course) or being a paranoid wimp and constantly having it behind you to prevent "over-exposure"! 
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Lech and Kappl do
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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| Quote: |
You are hardly seeking out sunny slopes??
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Why not? Skiing in the sun is great, and though you sometimes need to avoid the south facing slopes they are also useful in spring, when they soften up earlier.
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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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| pam w wrote: |
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You are hardly seeking out sunny slopes??
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Why not? Skiing in the sun is great, and though you sometimes need to avoid the south facing slopes they are also useful in spring, when they soften up earlier. |
Skiing in sunshine is great but the problem is snow quality. Can be rock hard in morning if not well groomed. In january, it gets churned up during the day, but after 2.30 or so the sun gets weak and the curned up snow can freeze again into a very dangerous and unpleasant surface with snow-rocks. In Feb you can have very hard snow in morning, and slush in afternoon, when most other slopes not really getting slush till march. Snow is one of best absorbers of radiation around so will rise in temp disproportionately if sun shines right on it. Snow condition is much more linked to sunshine and aspect than ambient temperature
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| Quote: |
| Snow is one of best absorbers of radiation around so will rise in temp disproportionately if sun shines right on it. |
If that were so we'd never have ice ages! Once a snow pack becomes isothermal at 0°c the temperature of the snow can not rise any higher. Snow most certainly does not rise disproportionately in temperature due to Sunshine - the air temperature might rise to 28°c with unbroken Sunshine, but the temperature of the snow pack will still be a maximum of 0°c. Dewpoint and RH can be more useful as indicators of snow quality than ambient temperature alone.
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You know it makes sense.
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In january, it gets churned up during the day, but after 2.30 or so the sun gets weak and the curned up snow can freeze again into a very dangerous and unpleasant surface with snow-rocks.
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That's a bit of a generalisation. or even a lot of a generalisation. When temperatures are low, and days short, south facing slopes can be perfect all day long and nice again in the morning. And they can be excellent well into February too. My apartment is at 1550m on a south facing slope so I am a bit of a connoisseur!! Can certainly get slushy late in the season, and frozen first thing, but most of the time it's fine.
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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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South facing slopes deteriorate much more rapidly (and lose their snow earlier in late season). Also, due to prevailing wind in the Alps, North facing slopes tend to collect more snow (being the lee slopes). This is why most ski resorts tend to develop primarily to take advantage of North facing slopes.
However it is nice to ski in the sun when the snow is new. 
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Poster: A snowHead
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Winterhighland, your argument is not logical. When snow at O degrees absorbs energy, it melts. Snow is a better absorber of radiation and shows greater temp rise than concrete
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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[quote="peanuthead"]
| pam w wrote: |
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You are hardly seeking out sunny slopes??
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Snow is one of best absorbers of radiation around so will rise in temp disproportionately if sun shines right on it. |
Only one flaw here. It isn't.
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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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emwmarine, confusing quote - I didn't write anything about whether or not snow is a good absorber of radiation.
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You need to Login to know who's really who.
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Sorry Pam I think it was peanuthead.
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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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| peanuthead wrote: |
| Winterhighland, your argument is not logical. When snow at O degrees absorbs energy, it melts. Snow is a better absorber of radiation and shows greater temp rise than concrete |
Yeah and then it's water not snow.
White things reflect radiation, not absorb it. You need a course in basic science,
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under a new name, not all correct. Believe it or not snow absorbs radiation very effectively and in fact is one of most effective substances in nature to do so
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| peanuthead wrote: |
| under a new name, not all correct. Believe it or not snow absorbs radiation very effectively and in fact is one of most effective substances in nature to do so |
easiest way for you to give us an indication that you might be correct is to link to some scientific articles...but basically......no.
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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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Winterhighland, it's getting 17 hours of Scottish sunshine, which is much colder than other kinds, as I remember. 
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peanuthead, from wikipedia I know, but hey!, " Albedos of typical materials in visible light range from up to 0.9 for fresh snow to about 0.04 for charcoal, one of the darkest substances. "
Now, visible isn't IR, but still this makes fresh snow the LEAST absorbent material in the list. http://en.wikipedia.org/wiki/Albedo
Going to try an correct me again?
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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Lizzard, no comment!!! 
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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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Snow absorbs SOME kinds of radiation well, but not infrared or optical, it depends on the wavelength. Bear in mind that 'radiation' means all electromagnetic waves from radio waves (wavelength of 10^3m) through IR (10^-5m) and visible light (0.5x10^-6m) and right up to Gamma radiation (10^-12m)
Here's a rather good study of the optical properties of snow.
http://www.atmos.washington.edu/~sgw/PAPERS/1982_RGSP.pdf
The IR albedo is more sensitive than the visible albendo to a number of factors (e.g. grain size and zenith angle)
The biggest factor in light absorbtion by the snow pack is the zenith angle. As it approaches 90 degrees/perpendicular to the slope angle, the absorption reaches it's maximum. As the angle decreases until it is (theoretically) parallel to the slope angle, the absorption reduces to zero.
It's the zenith angle that dictates that snow will melt faster in the spring, with the sun higher in the sky and for longer periods, the IR absorption of the snow is far higher than in midwinter.
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http://www.snowman-jim.org/papers/rambler.html
Just a quick web ref I can copy and paste from my phone, but any textbook or even avalanche handbook will provide all information to settle this
Snow has very high albedo at wavelenghts shorter than visible light. At visible light wavelengths it is near perfect reflector. But at short wave (uv) is is near perfect radiator. Ie it is rapidly heated when exposed to uv contained in sunlight, (and rapidly cools at night). It reflects IR which we associate with heat.
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You know it makes sense.
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UV doesn't do heating or cooling. IR is the heating component of the electromagnetic spectrum and it's at a longer wavelength than visible light.
Melanonin in skin, for example, can absorb UV and output IR but that's part of a biochemical reaction, not (as far as I know) something that a relatively simple crystalline structure such as snow or ice can do.
I think your author is confusing the range of wavelengths within the IR spectrum with the wavelengths of the electromagnetic spectrum in general.
The wording is inconsistent and a little misleading imho
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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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feef, there's no confusion. I am afraid your extrapolations are completely misinformed, and you are being quite emphatic about something you don't fully understand. And you won't learn it on wikipedia either I'm afraid
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Poster: A snowHead
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| peanuthead wrote: |
| feef, there's no confusion. I am afraid your extrapolations are completely misinformed, and you are being quite emphatic about something you don't fully understand. And you won't learn it on wikipedia either I'm afraid |
scientific evidence wouldn't usually be a link to an anonymous blogger. Feef is correct about the properties of UV v's IR. Not sure about the irrelevant bit about UV adsorption anyway. Isn't the reflected UV responsible for much of the goggle tan?
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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peanuthead, I'm a bit lost to what your original point was, unless it was badly explained.
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| Snow is one of best absorbers of radiation around so will rise in temp disproportionately if sun shines right on it. |
With hindsight I'll ask disproportionately to what? A granite rock sitting on the same slope, with same aspect as the snow or snow on another non sunlit aspect? As you've agreed a rise in temperature can only occur if the snowpack or part of it was below 0°c in the first place. Your statement about absorption of radiation was completely unqualified.
On a Sunny day with no snow on the ground, the ground will absorb the incoming radiation and warm up, radiating longer wavelength infrared that heats the air due to greenhouse gases, and the boundary layer additionally by conduction and convection.
On a Sunny day with snow cover a much larger proportion of incoming radiation simply gets bounced back (at wavelengths that do not heat the atmosphere) and some energy will go into melting snow. Because the surface has not heated up to the same extent, snow cover will suppress daytime maximum air temperature compared to what the same solar inputs and weather would give with no snow cover.
At night the air temperature under clear calm conditions will fall much lower with snow cover on the ground than without - the sub -20°c nights in Highland Scotland nearly always come with extensive and reasonably deep snow cover, because snow is not just a great reflector it's a great radiator of longwave infrared radiation and under clear skies with low RH results in much enhanced radiative cooling.
Gradient as well as sun and aspect come into play, feef talks about Zenith angles, one factor here in Highland Scotland is that the Sun is much lower in the sky than it is in the Alps. Thus steeper gradient slopes have an angle of incidence which favours solar warming in the depths of winter, and why (in combination with atmospheric conditions) at Glencoe in February this season, the Flypaper and East Ridge were luscious spring snow perfection while the gentle run outs over the plateau were unadulterated boiler plate. Oh ...and God Help anyone who went on the Flypaper 10minutes too late!  
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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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thanks for the science lesson folks, the reason i need to know is that i'm skiing the first week in january in 2014, and i just want to maximise my chances of a bit of sunshine, i usually go in march, but after breaking my arm this year i want to get back on the slopes as soon as possible..
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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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| peanuthead wrote: |
| feef, there's no confusion. I am afraid your extrapolations are completely misinformed, and you are being quite emphatic about something you don't fully understand. And you won't learn it on wikipedia either I'm afraid |
Where did I refer to Wikipedia?
One of the papers I have read, and which I linked to, was published in the journal Reviews of Geophysics and Space Physics.
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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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| compostcorner wrote: |
| thanks for the science lesson folks, the reason i need to know is that i'm skiing the first week in january in 2014, and i just want to maximise my chances of a bit of sunshine, i usually go in march, but after breaking my arm this year i want to get back on the slopes as soon as possible.. |
Knew it would be a simple explanation
Skiing in the sun (on reasonable snow) is one of life's pure pleasures.
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You'll need to Register first of course.
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compostcorner, Don't blame you. Think about your accommodation, too. Some places in deep valleys can get very short sunny hours in January. I stayed in one place in Les Houches and hadn't thought about it, but I spent a day in the chalet, reading, because of an injury and because it was warm weather (January, but still very warm, the snow was rubbish) I was sat out in a deckchair. But not for long enough - the building was in the shade most of the day. It's nice to be up on a south facing slope. I skied with some friends in our area, a couple of years ago, and he sulked if he had to ski in the shade. Made me really think about where to go to find the sun!
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| compostcorner wrote: |
| thanks for the science lesson folks, the reason i need to know is that i'm skiing the first week in january in 2014, and i just want to maximise my chances of a bit of sunshine, i usually go in march, but after breaking my arm this year i want to get back on the slopes as soon as possible.. |
A personal and longstanding thought of mine is that early January by far and away the best thing to do if you are not a large party is to wait and see where there is good snow, not much point in having nice sunny slopes if they are bereft of snow as occasionally happens in early January.
Plenty of cheap last minute deals to save money as well.
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yes, I'd agree with that - a last minute booking makes good sense at that time of year.
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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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that is the plan.
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I have checked my reference books re effect of solar radiation on snow
Snow acts like a black radiator of infrared. Ie it absorbs the energy from IR waves very readliy and heats up. The change in temperature is far in excess of surrounding air. Thus snow can melt under direct sunliight particularly if it is shininh more vertically as would be case with south facing slopes, even though ambient air temp can be well below freezing. It then re-radiates heat away at night and refreeezes. Refreezing can occur even if ambient air temp is above zero, but can be significantly impaired by things that impede radiation such as cloud cover
It is misperception that snow reflects IR because it reflects visible light. This does not bear on heating effect of sun on snow
Basically no one is really arguing that snow on south facing sloppes is always first to suffer
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