Camping in snow or slush

Transcription

1 Camping in snow or slush Pitching tents Ground insulation Sleeping bags Stoves Water bottles Eye protection Skin protection Emergency equipment Clothing Blizzard jacket Overpants Ideas and tips for comfort and safety Snow construction Many people think that there could be few experiences less enticing than camping in the snow. However, snow walking, snow shoeing, ski touring, back country snow boarding and snow camping are popular among outdoor enthusiasts and leaders of these groups. For a party to enjoy these activities safely and with some degree of comfort, all members of the party must be well equipped and have a sound knowledge of overnight bushwalking and camping skills. The basics for snow camping are almost the same as for regular bushcamping, the major difference being the higher standard of equipment and knowledge required. There are a number of 'tricks of the trade' which can make a big difference to the safety and comfort levels of snow camping.

2 Tents A double-skin tent with a sewn-in groundsheet is recommended for snow camping. There are two main advantages of a double skin tent: the air space between the inner and outer provides some insulation, and condensation forms on the outer of the tent, if the inner layer is made of a breathable material. Sewn-in groundsheets do not generally slip on snow. Separate groundsheets should be securely pegged down. Most good quality modern bushwalking tents are suitable for snow camping, but some modifications may be required. These include cords attached to the bottom eyelets of the tent, and bearing plates (billy lids or aluminium discs) on the ground for tents with weight bearing poles. The bearing plates stop the poles from disappearing into the snow. To avoid losing them, drill a hole into each one, and tie one end of a cord through it, and the other to a bottom eyelet of the tent. The sloping sections of the tent need to be taut and of sufficient pitch to allow snow to slide off. A vestibule (an unfloored tent area outside the inner tent but inside the fly) is virtually essential. Pitching tents To pitch a tent in the snow, select a sheltered campsite, avoiding snow-laden trees. Prepare the tent site by trampling down the snow until it forms a hard, level platform. Trampling is best done in boots, as skis do not generally give enough pressure to compress snow effectively. Once the site is well trampled down, ensure it is level and smooth, best done using skis. Pitch the back of the tent into the wind, preferably with the door facing across or down the hill, as cold air travels down hill and should go around the tent, not into it. Peg down the base of the tent using snow pegs or dead sticks that are cm long. Snow pegs save time and environmental damage. Loop snow pegs or sticks into the cords that are attached to the bottom eyelets, push the pegs into the snow, and pack the snow down by stamping. These cords, about 50 cm long, should be attached to all the points on the tent normally secured by pegs. If the sticks get frozen in, the cord can be cut and the tent removed. Then there is plenty of room for the pegs or sticks to be removed using boots, a snow shovel or similar tool, without the risk of damaging the tent. The roof guys and tent-pole guys are tied or looped to dead sticks that are cm long and the sticks driven into the snow. Remember to leave about 25 cm of stick out of the snow since this makes it easier to pull them out when the tent is taken down. Before leaving the site these sticks should be scattered to remove any trace of your presence. Plastic bags can be used instead of tent pegs, by filling with snow and tying to the guys and cords as before, then burying them. However, the can be difficult to get out later, and must not be left behind. Another way of anchoring the tent is to stamp a small trench parallel to the tent where you would normally put a peg in. Thread a stick through the extra piece of cord attached to the tent, place it horizontally in the hole and stomp snow down on top to bury. These dead men hold very well the only problem with this method is getting the sticks out later. Always try to keep the inner tent dry. This may mean laying the fly over and putting the two up

3 together, or pitching the fly first which is possible with some tents. Take an extra sponge or synthetic cloth to mop up any snow or water getting into the tent. If it rains, check the pegs regularly as they can be washed out. If it snows make sure the snow is knocked off the tent regularly or the tent can collapse under the weight. Ground insulation It is essential to have adequate insulation between your sleeping bag and the snow. A closed-cell foam sleeping mat is the lowest cost and most reliable option. Thin groundsheets or space blankets are not sufficient. Use your pack or a folded parka under your feet. Ordinary foam rubber is too heavy and absorbs moisture, while plastic air mattresses are unsatisfactory as they puncture easily, and the air inside does not warm up. Self-inflating, sealed-cell foam insulated sleeping mattresses (e.g. Thermarest), are excellent but expensive and can puncture. Another possibility is a closed-cell foam mat but with 1 cm egg-carton type bumps on one side. This doubles the insulation without doubling the weight, but is somewhat more bulky. Closed-cell foam is also available in 2 3 mm thickness, which is excellent for providing insulation and reducing condensation by covering all the tent floor. Sleeping mats are then placed over the top. Sleeping bags Sleeping bags for snow camping should be of a walled construction and filled with duck or goosedown and have a large draw-cord hood. Other points to look for in a sleeping bag are: loft the greater the loft the warmer the bag shape/fit which design best fits your shape, the extent that you move inside a bag, and how claustrophobic you are outer material (Gore Dryloft reduces dampness, but is expensive and makes the bag heavier) baffle design smaller down pockets are generally more effective in keeping the down where it is meant to be foot design for mummy bags a shaped foot is likely to improve comfort/ warmth zips let in cold draught tubes stop cold, but add weight. There are some good synthetic fibre bags on the market that are much cheaper than down bags. They dry much more quickly if wet, but they are generally heavier and bulkier to carry, and they do not seem to last quite so long. Manufacturers temperature guides for sleeping bags are just that guides. Some seem too cold, others too warm, and people have different insulation needs to feel comfortable. You will need to come to your own conclusions. An inner sheet will make a bag a few degrees warmer, and will prolong the life of your bag by keeping it clean. Cotton is cheaper, silk is lighter and slightly warmer but more expensive.

4 Stoves Kerosene or white spirit (Shellite) stoves with a pump are best for cold conditions. Gas stoves will not work satisfactorily because the liquefied gas will not vaporise in cold conditions. It is essential to carry sufficient spare fuel, as a lot of heat is required to melt snow for cooking and drinking purposes. A cm piece of three-ply timber or cork placed under the stove will stop it disappearing into the snow. Kerosene stoves will require more priming than usual, and some white spirit stoves also need priming when used below zero. Stores must always be lit entirely outside the tent. Cooking should be done with the stove completely outside the tent or in the vestibule. Never, ever cook inside the inner tent. Matches Each box should be sealed inside a plastic bag. Moisture-resistant or special windproof/ waterproof matches light better in wet conditions. Cigarette lighters work well also. Water bottles Running water can be extremely scarce above the snow line. About 1 litre of water should be carried as a minimum. Leave your bottle of water in your pack or tent overnight to avoid freezing. When collecting snow for water, always collect fresh-looking snow, well away from huts. Ice crystals and icy snow contain more water than an equivalent volume of powder snow. Always add snow each time you drink, as some water remaining in the bottle will thaw the snow more quickly. It is not recommended to eat snow directly, as the energy required for your body to melt it results in heat loss. Torch and candles These are essential items because of the shorter daylight hours. Cooking after sunset is common. A head torch allows for greater flexibility, especially while cooking. Candle lanterns reduce fire risk and are fairly windproof, but are heavy, have low light output and generally require expensive candles of a specific shape. Food Food for snow camping should be high energy value and it should require a minimum of preparation and cooking. See Chapter 27 for food ideas. Eye protection

5 Good quality sunglasses or goggles with side protection and an eye protection factor (EPF) of at least 10 are essential and should be worn throughout the day. Reflected sunlight from snow can lead to painful and dangerous snowblindness if goggles are not worn. Even on dull days it is possible to get severe headaches. Straps for keeping glasses in position are available, and they can prevent loss or damage to the glasses in falls. Double-lens goggles are less prone to fogging up, but are more expensive. Many experts suggest goggles are better for poor weather and sunglasses are better for sun. Skin protection All exposed skin must be protected. Do not neglect areas such as the lips, under the chin, the nose, and the ears, which are easily subject to rapid sunburn in snow conditions. Protective sunscreen with a minimum sun protection factor (SPF) of 15+ is essential. Avoid so-called quick tanning creams, as they may give the impression your skin is protected when it is not. Emergency equipment The following items should be carried by each party member at all times: a survival blanket or bivvy bag whistle waterproof matches some food torch map and compass personal first-aid kit water bottle. Clothing Several thin layers of clothing are desirable. Air is trapped between the layers and this provides very efficient insulation. This system also allows for flexibility in adjusting to variations in temperature. Heavy sweating should be avoided as it wets clothing and reduces the value of the insulation. Try to keep comfortably cool by stripping the outer layers early if you get warm. Many older bushies prefer woollen clothing for snow conditions as it is warm even when wet, compact to carry, and breathable. Synthetic clothing can be extremely good, but check for bulkiness and windproofness. Underwear Synthetic underwear (polypropylene, chlorofibre) remains relatively dry even with heavy sweating, and is therefore an advantage in snow activities. String or mesh singlets are also good for snow walking as they trap a large amount of air in the mesh. Warm tops

6 One or two light synthetic shirts/tops or light woollen jumpers worn over a skivvy or T-shirt give extra flexibility in temperature control. Heavy woollen jumpers should be avoided. Fleece jackets, although bulky, are light and dry quickly if they get wet. A windproof outer shell is required with some of these jackets to retain body warmth; others are reasonably windproof. Trousers Long loose-fitting woollen trousers, below-the-knee breeches or warm synthetic pants suitable for snow can be worn. Breeches can be made by cutting off part of the legs of normal trousers (leaving at least 15 cm below the knee) and finishing the trouser legs with a split-case cuff secured with tie buckles or a strip of velcro. Some types of ski pants, e.g. stretch nylon or Lycra are not suitable as they provide insufficient insulation. Tight and wet jeans can be deadly in the snow, due to the wicking effect greatly increasing heat loss from the body. Socks Two pairs of woollen socks provide the best combination, one light thin pair next to the skin, and a long, thick pair on the outside. Warm feet in the snow are important. Allow at least one pair of spare socks for wearing at night. Mittens Two pairs of mittens are recommended a pair of greasy-wool or closely knitted woollen mittens, and a separate pair of proofed-nylon, Gore-Tex or oiled japara over-mittens. Fleece mittens with a waterproof nylon outer are also available. Rubber dishwashing gloves are useful for situations where hands get very wet, such as building igloos, snow caves or shelters. They are also useful for activities which may otherwise require bare hands, such as tent pitching or stove lighting, but cannot be used alone for any length of time as they provide no insulation. Warm hat It is important to remember that up to 30% of the body s heat loss may occur through the head. A suitable warm hat is essential for keeping the head warm. Fleece is generally considered best; although wool is very good, some people are sensitive to wool next to the skin. Gaiters Gaiters are used to prevent snow from entering the top of boots. They generally have elastic or drawstrings at the top and bottom, and a strap under the instep of the boot to prevent them from riding up. They are made of heavy proofed nylon, canvas or Gore-Tex. Knee-length gaiters are an advantage in deep snow. Front fastening gaiters are suggested as better than rear, but Velcro and studs can be serviceable. Zip fasteners on gaiters are rarely satisfactory, as they become fouled with dirt. Yeti gaiters, which fully enclose the boot and lower leg, provide superior waterproofing for boots, but are very expensive. Boots Good boots are essential. One-piece leather boots with a good tread are the best. Old boots and lightweight boots with Cordura, suede or canvas inserts are not suitable for snow walking since they are likely to leak, making your feet wet and cold. Wearing plastic bags between socks and boots is not recommended as it prevents breathing and your feet become just as wet from your own sweat.

7 Boot proofing Boots should be warmed in the sun or in a warm room before and after applying the proofing. They should be proofed several times, starting a week or more before they are needed. Suitable proofing materials such as Sno-Seal or Nik Wax should be used. Bootees Cordura/Gore-Tex bootees lined with wool or synthetic fibre can be very comfortable for camp use, but are expensive and probably a luxury except for extended winter trips. They can be sewn by a handyperson for a very reasonable cost. Blizzard jacket The jacket should be made from waterproof, windproof but breathable fabric. Your jacket should be loose fitting and have a draw-cord hood. It should be long enough to sit on when being worn. Overpants Overpants should be proofed nylon, oiled or dry japara or Gore-Tex. Overpants are essential for providing insulation for the legs in rain with strong winds. They should be large enough to put on over boots some types have zippered legs to facilitate this. Models with full-length zips detachable at the waist can be put on without removing skis, which may be advantageous enough to justify the additional cost. Ideas and tips for comfort and safety Clothing for sleeping Clothing for night use should not be part of your normal day clothes. Suggestions for night clothing are wool or synthetic (polypropylene, chlorofibre) singlets, tracksuits, or long johns and socks. Keeping pack contents dry Most packs are not waterproof in rain or snow. Place a heavy duty 240 litre bin liner bag or garden clean up bag inside your pack, and put everything inside this. Pack every item of clothing, food, etc. in plastic bags. Also carry spare plastic bags, including a 240 litre bin-liner bag for use in hypothermia treatment. Preventing frozen boots Frozen boots are unpleasant, so try to prevent them freezing at night. Keep them inside the tent. Some walkers and skiers wrap them in plastic bags and stow them in or at the feet of their sleeping bags. Dehydration Have plenty to drink, as dehydration is a common problem with snow walkers and skiers. Do not swallow snow, as it can cause stomach cramps. If you have to eat snow or ice, let it melt in your mouth before swallowing. This is not recommended, due to the body heat loss from melting snow. Toiletting in the snow Toilet activities should be performed well away from huts and summer tracks, and your waste should be buried deeply in the snow. Where the snow cover is light enough, a hole should be dug down into

8 the ground. Many areas above the snow line have or are considering regulations which require faecal waste to be carried out. The best method seems to be allowing faeces to freeze, then carrying in heavy plastic bags in outer pockets of the pack, or in a poo tube made from 100 mm PVC pipe. Plastic barrels for a group can be towed on a sled if snow cover is good. Remember to empty as soon as you reach a toilet. Walking in snow Walking in snow is discussed in Chapter 14. Use of huts For comfort and cleanliness, many skiers and walkers remove their boots and pull plastic bags over their socks or wear bootees while moving around inside the hut. Snow shovels Snow shovels are indispensable for a wide variety of snow construction and general camp activities. Special equipment for snow and ice climbing An iceaxe, instep crampons, crampons and ropes are not normally necessary for snow walking, but are essentials for snow climbing. These are specialist items of equipment, so learn the correct way to carry and use them. Snow construction It is a good idea to dig a trench knee deep or more inside your vestibule to help get into and out of your tent. This should be filled in before you leave. If the wind changes or you can t get out of the wind it is possible to build a shelter around the tent using snow blocks. Igloos Commence by marking out a circle of the diameter you require on flat ground about 2.5 m is a minimum, but up to 4 or 5 m will accommodate up to five or six people. Cut blocks of snow about mm long, and lay them outside the circle. Cut the blocks from outside the igloo do not lower the floor level, as cold air will drain in. Igloos are built as a spiral, and the door is cut at the end. After laying, the first layer of blocks must be cut to form the base of the spiral, by trimming them so that the top slopes inwards, with the height increasing smoothly and gradually from ground level to the full height of the block by the end of the layer, as shown in Figure 13.1.

9 Continue laying blocks as you move around the spiral, always leaning them inwards. The last block will be round and conical like a cork from a large jar. The door is cut next to last, and then a protective tunnel can be built. Once inside, smooth the inside very carefully, as any low points will drip. Any cracks should be filled with snow from the outside. A snow shovel, a pruning saw or a plywood platform used to support your stove could be used to help build or cut blocks. Rubber washing-up gloves are also useful for handling the snow blocks. Snow construction can be hot work, so don t forget to drink while working. Snow caves Digging a cave in a deep bank of snow can produce a comfortable and secure living space if conditions are ideal. However, in bad weather or unstable snow it can be a dangerous venture. In 1999, near Mt. Kosciuszko, New South Wales, a group of snowboarders died in a snow cave they had dug. Snow caves are built by digging into a large snowdrift or bank. Dig an entry tunnel, starting at the base of the drift, initially in horizontally, then angling upwards. When in about mm, start digging the cave upwards and out on each side. One person should dig the cave inside, while another will be needed to clear the entry tunnel of snow from the cave. The floor of the cave should be above the top of the entry tunnel, so cold air cannot drain in. Smooth the roof very carefully, as any low points or bumps will drip. Make a ventilation hole in the roof with a stock. Snow cave construction is very hot, very wet work, and good waterproof jackets, overpants and mittens are essential.

10 Leaders should be aware of some serious risks associated with snow caving. If the cave is made too large or the snow is soft and wet, the roof may collapse onto the occupants. A cave should be no larger than is necessary to provide sleeping space and the roof should be carefully domed. If any cooking is done in the cave, then good ventilation must be provided, with the entrance lower than the sleeping platform and a chimney to permit exit of steam and carbon dioxide and carbon monoxide. If the entrance is higher than the cooking area then carbon monoxide, which is heavier than air, may settle in the lower portion of the cave and can threaten the lives of the occupants. If fresh snow falls through the night it is highly likely that the entrance to the cave will be filled with snow. A total blockage can lead to suffocation. It is useful to keep a stock or other suitable tool inside the cave to create air holes in the roof if needed. Where a cave is dug into a slope which has distinct layers of snow, a large slab of unstable snow could break away and slide down the mountain taking skis or any other gear with it. The occupants of the cave may find themselves exposed to the elements or the entrance to their cave may be blocked by the slide. Both these have occurred in Australia. One group lost important gear in the slide, which was effectively a small avalanche. All things considered, a good snow tent, well pitched in a sheltered site or with windbreak walls built around it is generally a safer shelter.