Information about snow in general - what is it, how it forms, weather patterns that bring snow, snow making, snow grooming, different types of snow and stuff.
What snow is
Snow is precipitation. If forms when water freezes on nuclei, forming characteristic symmetric six sided crystals. Apparently no two snowflakes are identical, but I haven't looked at them all.
As a general proposition, snow will melt down to a depth of water 1/10 its depth as snow, but this depends on the moisture content of the snow. The lighter the snow, the smaller the amount of water when it melts. Generally, snow that forms in warmer temperatures and in areas of greater humidity is heavier.
Basics on how to interpret a synoptic chart looking for key things like cold outbreaks and cutoff lows. What on earth is a 540 line and why do people talk about it? What does cold snow bearing cloud look like on a satellite image? What pet theories are then on predicting snowfalls or the season ahead? What about the future and global warming, what impact will that have on us?
What is the difference between a fan gun and an air/water gun? Under what conditions can you make snow? What is the difference between natural snow and the man made stuff?
There are even some home made snow guns operating in Aussie suburbs.
What about cloud seeding?
Groomed slopes are often called "piste" while runs that are not groomed are called "off-piste".
When a ski run is groomed, it has had a snow tractor ("sno-kat") drive over the ski run with special grooming equipment attached. The purpose is to flatten any bumps created by traffic and remove any unseen hazards such as dangerous ice patches. The final result after a slope has been groomed is a super flat and smooth run free of any hazards that could affect your skiing or snowboarding. The grooming machines leave a surface that looks like corduroy, and groomed snow is sometimes referred to as corduroy.
Types of Snow
- Corduroy: The surface left after a grooming machine has finished with snow. Corduroy describes the appearance oof this snow before boarders and skiers sink their edges into it.
- Corn Snow: Usually found in the Spring, this snow is characterized by it's large, corn kernel size granules. Also known as Ego or Hero snow as it is very easy to ski on and very forgiving.
- Crud: Heavy, wet snow (although other opinions exist)
- Crust: Snow that has a crust on the surface. Generally formed by light rain/mist freezing on the surface, trapping in the dry snow underneath.
- Death Cookies: Large frozen lumps of snow created by poor grooming, avalanche debris, crumbled cornices etc. Deadly when hit, and even worse when covered by a layer of new snow so they are invisible.
- Ego Snow: See Corn Snow.
- Elephant Snot: Similar to wet snow but characteristic of Aussie conditions when you get nice dry snow and then it warms up and turns to the consistency of porridge.
- Freeze Dried: Snow that has a lot of moisture sucked out of it by a heavy frost. This type of snow can sometimes has similar properties to powder.
- Hard Pack: When natural snow becomes firmly packed by repeated grooming or continuous wind exposure. Often snow that has never melted or recrystalized.
- Hero Snow: See Corn Snow.
- Horizontal Snow being blasted horizontally by a blizzard.
- Icy: Icy is a hard, glazed surface created by one or a combination of the following: freezing rain, rapid freezing temperatures or saturation from ground water seeping up into the snow and then freezing. This type of snow often has a translucent appearance.
- Machine Groomed: Loose granular snow that has been repeatedly groomed by power tillers.
- New Over: This snow is used to describe any accumulation of snow over an existing surface, for example "New over packed powder" or "New over machine groomed".
- Packed Powder: Powder snow that has been packed down up the above mentioned forces. It is no longer fluffy, but not hard snow, either.
- Powder: The product of fresh, natural snow. Cold, new, loose, fluffy dry snow that has not been compacted by skier traffic or grooming.
- Porridge: See Elephant Snot.
- Sastrugi Firm (if not icy) windblown ridges.
- Sierra Cement: See Elephant Snot - term used mostly in the Sierra Nevadas in California as their snow isn't as dry as places like Colorado
- Slurpee Park: See Elephant Snot.
- Slush: Typically Spring snow that has suffered the effects of high temperatures and becomes very wet.
- Spring Snow: Generally used in the same context as corn snow, but can be used to mean the full cycle of snow that occurs in Spring, ie: firm in the morning, softening to corn snow, then possibly slush.
- Wet Snow (Wet Pack): Snow that has become moist due to thaw or rainfall. Snow with a high moisture content when it fell.
- Wind Blown Pockets: Dry snow that accumulates in valleys/depressions from being blown by the wind.
- Wind Packed: Fresh snow that has been packed by the wind. Generally, this snow is dry.
- Wind Polished: Ice, in resort snow report speak.
- Yellow You don't want to know. Not to be eaten.
- Cornices are steep, often overhanging snow drifts that form on the lee side of ridges. As the wind crosses the ridge it slows down, and windblown snow is deposited. The drifts formed in this way can be very deep - much deeper than surrounding snowpack. Cornices are often unstable and the lips break away and roll down hill. Sometimes the whole cornice will slide.
- Snow Angels Shapes kids (or adults) make when they lie in the snow on their back and flap their arms up and down. It makes the shape of wings in the snow and combined with the body imprint leaves the shape of an angel.
- Snow Ghosts Snow ghosts are trees covered in snow and ice shaped by wind and sun. What causes Snow ghosts?
Types of Lift
- Aunty Jack Lift Alternate name for a rope tow. So named because they rip your bloody arms off, the catch cry of Aunty Jack.
- Chairlift Self explanatory. A chair suspended from a cable that carries you up the mountain. In the olden days most chairs were doubles (although there are some singles). As time, technology and loading and unloading methods advanced quad chairs arrived. Then sextuples. There are now 8 seater chairs, which operate with surprisingly little carnage at the top. There is one at Perisher.
- There are two basic types of chair:
- Fixed grip The chair travels through the loading station at the same speed as the cable.
- Detachable Chairs are clamped to the cable, but are detached as they enter the loading or unloading station. The chair travels slowly while peeople get on and off, but travels quickly for most of the ride.
- Detachables move more people than fixed grips. There are lifts that are a hybrid of these two types, such as those that use a moving carpet to accelerate riders up to the speed of a fast moving fixed grip chair.
- Combined Lifts Basically a mix between a chairlift and a gondola on a standard detachable lift. An example would be the Horse Hill Lift/Gondola at Mt Buller which consists mainly of chairs and some gondolas grouped in fours.
- Gondola Similar to a chairlift, but fully enclosed. Sitting down. Out of the wind. Quick. The happiest lift of them all. There are rumours of certain clothes optional activities during longer rides, but truly dedicated folk are concentrating on their next run.
- J-bar A drag lift where a large disc is placed between the legs which drags you up the hill. Also called Pomas, but Poma is a tradematk of the Pomalgalski Lift Co, so you should not call it a Poma unless it is a Poma. Sometimes called Cheap Thrill Lifts. I don't know why. Do not shout "Single!!" People will love you, but you will look like a goose.
- Jig Back Gondola A strange one. There are two groups of gondola cars that shuttle backward and forward, reversing direction each time. There is one of these at Seaworld on the Gold Coast. They are not much use as a means of moving people up a hill, but are sometimes used as people movers. There is one at Panorama in Canada.
- Lateral Ground Transportation System What Alta, with tongue firmly planted in cheek, calls a rope tow.
- Magic Carpet A conveyor belt that takes beginners up th hill. Simple, not intimidating and effective.
- Nutcracker These are essentially rope tows, but you get pulled up by attaching a nutcracker (a belt with large metal clamp that resembles a nutcracker) to the rope. This allows you to go up very steep slopes that would be almost impossible to get up if you were just grabbing onto the rope. Nutcracker tows are the usual type of lift in the New Zealand club ski fields.
- Rope Tows The simplest lift of them all. A rope goes round and round. You grab it, and are dragged up the hill. Crude but effective.
- T-bar A surface lift. This means that the rider remains on the surface of the snow. Also called a drag lift. The rider is dragged up the hill. A horizontal bar is tucked under the backside of the riders, and they are dragged uphill. Drag is an important concept. If you sit on a t-bar you fall off. People will laugh. T-bars are designed for two people. If, through incompetence (and I am looking at you, snowboarders), or ignorance you ride single when there is a crowded line people will laugh and hurl abuse. If you are alone shout "Single!!" and someone will probably join up. It could be the start of a beautiful friendship. At the very worst you will find that your observations about the weather and conditions are shared by a total stranger. Riding a T-Bar.
- Tram or Telecabine A big box containing heaps and heaps of people who are whisked uphill.
Snowdepths in Australia
Snowy Hydro have been tracking snow depths in the NSW mountains for many years. They have a snow depth chart on their web site, which allows you to call up charts for snow depths at 3 locations in various years, and to compare different years. The data for Spencers Creek most closely matches the depths in the actual resorts. It is not a perfect match.
In Victoria, the snowdepths are traditionally measured by the resorts themselves. Many years ago there were lots of accusations of inaccuracies. However with the advent of snowcams people are easily able to check the accuracy for themselves. Most resorts have an offical measuring post for natural depth (for example Hotham's is in the trees next to the road runner lift). There are also measurements taken in an area that is representative of snowmaking depth.
Snowdepths and Conditions in North America
America generally has a better and longer snow seasons than the Australian ski resorts due to their weather system and altitude of the ski resorts. Average bases can range from 2 metres deeps to a massive 10 metres deep depending on the ski region. Be warned though that even though the snow conditions are much more reliable than in Australia, they do too have bad seasons that struggle have any terrain open.
For more information about snow depth in US, visit this site. This site has an incredibly detailed analysis of snowfalls in North America spanning many years.
This category has only the following subcategory.