Is it dangerous to sleep in a tent alone in a forest in -20°C?

Piece of cake.

I was working for St. John's Cathedral Boys' School in the late 70's. The school had a winter program that included week long dog sled expeditions. We had the odd case of frostbite, but nothing serious.

On a bet, I slept under a tarp for a year. It wasn't a fancy setup. I started in the fall, and threw a tarp over a large willow bush, bent the branches, and tied the corners down to near by shrubs. I ended up with a 5' high 8 foot diameter bubble. I then put a foam pad underneath.

I knew I was pitching for the long haul, so I picked a high spot that I was reasonably sure wouldn't flood in the spring melt.

Once a week I'd bring my sleeping bag in to the house to dry it thoroughly. Or if the day looked clear, I'd lay my bag on the roof to dry out.

Minimum temperatures during that time were about -45 C

Sleeping out in winter is not a big hazard.

Winter travel is far more hazardous. I've done a few solo hikes in cold winter (below -15 C). The hazard is a slip and fall. A badly sprained ankle in summer is a nuisance. You nurse it for a couple of days, and limp out. Skiing or snowshoeing on such an injury is far more problematic.

Incidentally: The span from -5 to 5 C (25 to 40 F) is the most dangerous time to be in the wild. It's hard to stay dry, which in turn means it's hard to stay warm. Below -5 snow tends to not melt on the surface of your clothing. Above 5 or 10 drying out with a fire is reasonable, and there aren't piles of snow everywhere.

posted about 10 years ago

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Sherwood Botsford‭

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Get a Lavvu with a stove!

^{Photo from Wikimedia Commons}

The Sami population of Lapland have lived for centuries in Lavvus in a climate with temperatures down to -40°C. They did decide about a hundred years ago or so to live in houses, because it is a tad more comfortable. As the Sami still exist, this proves that it's not immediately lethal to live at such temperatures. They did have a very high infant mortality, but I suppose you're not planning to give birth in the tent. A rather important point though: in a lavvu you can have a fire:

^{photo from the Norwegian UFO centre}

See also this discussion.

However, keep in mind that allemansrätten does not apply!. The Swedish right of everybody applies for short-term stays, usually 1–2 days. If you are planning to stay weeks or even months, you will need permission from the land owner, or stay on a proper campsite and negotiate a good price. The latter also has the advantage that you have a nearby emergency escape if things go bad (near a city there can be other dangers than cold).

posted almost 12 years ago

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gerrit‭

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Re: tent size and down sleeping bags

1. the bigger the tent is the more energy it takes to warm it up. You want a balance between space (to move around in) and energy here, so probably not something you can stand up in.
2. your sleeping bag should be fairly close fitting (i.e. not a rectangular bag). Same reasoning here as in #1.
3. be careful how much stuff you put on top of a down sleeping bag as this will compress the down and make it less effective. One exception is a bivy or waterproof liner outside of the bag (for rain/snow/etc). Bag liners that go inside the bag can add 5-10 degrees F.

posted almost 12 years ago

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Aaron‭

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-20 celsius is not particularly cold, but 3 weeks summer hiking experience is not particularly helpful. You might not kill yourself, but you probably won't thank yourself, either.

posted almost 11 years ago

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Andrew‭

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There is a definite danger of hypothermia depending upon the "type" of tent you choose to use. Eskimos live in -70F environments from one day to the next, so it is doable certainly. Native Americans as cited above have tents to provide for living in environments that commonly get to -50F (by keeping a fire burning inside the tent). A TeePee isn't what I would call portable; it's more of a temporary building (early mobile home).

But if you choose a tent that does not deal with the humidity produced by your sweat and breath, you can drench your sleeping bag AND clothing while you sleep. Moist means loss of effective insulation.

If looking for a semi-permanent place to live, learn from homeless people, or the traditional hobo. Solid walls make better wind barriers and newspapers provide excellent insulation if kept dry.

But if you want to use a backpack style tent:

Do not pitch a tent under trees. Branches falling can rip your tent.

Flooding for a backpack style tent in the winter is of no concern. So resting in a depression can block the wind.

I never started a fire; ever. I always used fuel just for cooking; really just heating food and drink.

Separate water bottles for bathing and eating.

You MUST have a closed-cell foam mat (or other non-compressible insulation like layers of pine needles) to lay on. This is NOT optional. Your weight will compress your sleeping bag. The warmth of your body will melt the ice/snow under the tent and 1) freeze you down, and 2) freeze the bottom of the tent and sleeping bag to the ground.

This is NOT subjective, this is personal experience. I used to backpack in the winter and when I first started out, I had a few things to learn. My first night it was 10F and my breath created frost on the tent inside the tent, and when the wind blew it would shake the frost down over me while I slept (snowing inside my tent). My body heat caused the frost to melt and saturated my sleeping bag (actually just very moist, not really saturated). I began to get cold and woke up groggily. It was a bit before I had the awareness of potential danger. I was only about 5 miles from home, so I got dressed quickly, even though my clothes were very moist (I was sleeping with them in by bag anticipating the morning cold). Cold, I hurriedly put everything on and started moving quickly to tear the tent down; frozen to the ground. I left it. I began running to build up my body heat. My pack was lighter because of no tent and no sleeping bag. I didn't want to start sweating, so I walked/ran to try to build body heat controllably. Was more difficult because my feet started to sweat (get cold from lack of effective insulation) before my body was warm. Once I was "comfortable" again I kept a fast pace until I got home.

Things I changed.

Good Willed my tent.

Fell in love with Gortex. Closed-cell sleeping pad. Arctic tent by Kelty (vented differently; Gortex liner lets moisture out and outer shell collects frost and slides down outside the Gortex liner). Gortex top sheet to lay over sleeping bag while sleeping (humidity out, moisture from frost stays out; a cycle of drying). Keep all my clothes hanging under the flap of my backpack at night (pull clothes in during morning to warm them up). Made lined Gortex tent bags for tent and poles, and wear these during the night for added insulation for my legs and feet (dual duty because weight is important; turn them inside out while hiking). Don't eat or drink anything within 3 hours of going to sleep. Evacuate before bed.

During the day, even at -10F (coldest I've been in), moving, eating, Sunlight, insulated foot gear, and head gear make a huge difference. But at night, none of that day gear helps.

I have almost always hiked alone. I prefer the winter because there are no insects. Sounds are softened. Water is clear. Fish are hungry. Animals are bold and visible. You can hike for weeks and not see anyone else. I stash supplies for long outings; for daily sustenance and for emergencies (keep hand drawn mylar maps of local area features and resources; cheap, and every trip it's something to do to keep the mind engaged).

Bathing is a wash cloth, and a bottle of water you slept with the previous night. Hair gets washed with the same wash cloth; no soap. Every day a water source is found, wash and wring the wash cloth out and hang it on the pack to dry while walking. Wash your feet daily also. If you are sensitive about mixing your hair and feet, then I suppose bring two wash cloths.

I keep a very small bottle of clear chlorine bleach in my pack. I put 2 drops in my bathing water bottle. This lasts for multiple outings. I use an ultraviolet sterilizer for my drinking water bottle.

You can use soap when near a water source to clean the wash cloth. But your body is at-risk for hypothermia if you drench yourself. You can clean part of your body while the rest of your body is covered. Then when warmed up again, wash the other parts.

At altitudes above 10,000 feet, do not bathe in water sources when air temperatures are below 60F. The higher altitude causes water to extract more heat from the body faster due to drier conditions and the related much greater evaporation.

I cannot address the needs of a woman, I've never backpacked with a woman. I've only backpacked in the Summer with my father during fair conditions. My summer packs have otherwise been solo except for one trip to a high mountain lake in New Mexico.

posted about 10 years ago

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no interest anymore here‭

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I know the base question is about survival but, based on your back story, one of my biggest concerns would be security.

During the day when you are away you will need to take everything you value with you or risk it being stolen. Even if you take everything with you thieves will not know that and may rifle through your belongings looking for something of value. During the night being alone will make has it's own vulnerabilities.

You mention moving every couple of days. Moving this frequently will probably place you in neighborhoods that you are not familiar with and presents a number of risks.

posted almost 12 years ago

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Brad Patton‭

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Yes, it is definitely doable. -20°C is only -4°F. The real question is whether it is doable by you at the level of discomfort and hassle you are willing to put up with. Only you can answer that. At best we can point out what the hassles and discomforts will be.

First, your fear of dying of cold in your sleep is silly. You'd have to do something pretty stupid to die of hypothermia, and even that's not going to happen when you're inside the sleeping bag. The main danger will be from frostbite, but that again would largely need stupidity to help it along, although that's easier to do than outright death from hypothermia.

Your tent will be a long term fixed installation you set up once at a time and conditions of your choosing. You can therefore afford a larger and heavier tent with more stuff you bring in once. Definitely get a tent you can stand upright in. That will make changing clothes much quicker and more comfortable. Since you should be able to keep water out of the tent, get a nice down sleeping bag and a few light blankets. The down bag should be rated for most nights, then put the blankets on top for the few unusually cold nights. Since again weight is not really a issue, get a full sleeping bag, not a mummy bag. They are simply more comfortable. Get a good insulating pad, and another two as backup. Get a tent large enough to fit your sleeping bag and something to sit on next to it, like a folding chair. Put something under the legs to spread out the weight to that they don't hurt the tent floor. Get one of those rubber-backed mats people sometimes put just inside their doors and put it just inside your tent. That allows a place to step with boots still on, then you can sit down on the chair with boots still on the mat to take them off. The crud stays on the mat, which you can shake clean by reaching outside after having put on your down hut booties.

Some things are going to be a hassle. At -4°F you want to keep your gloves on whenever possible, but some tasks will be difficult that way. You end up taking your gloves on and off a lot, trading off efficiency with cold fingers. Get a pair of polypro glove liners. They are thin and still allow many tasks to be done, but provide at least a little insulation. Their main advantage is that any metal you touch won't immediately conduct the heet from your hand away. Touching bare metal at -4°F is a good way to get frostbite.

Be prepared for some discomfort no matter what equipment you have. The toughest part will be getting yourself out of the sleeping bag in the morning. You'll really have to will yourself to leave the warm comfort of the bag and get into the air at probably the coldest part of the day. At some point you'll have to change your clothes and get undressed in the process. That's going to be cold. It won't be cold long enough to be any real danger, so it's really a mindset issue to get over. Whether you can or not and are willing to push yourself in that way only you can say.

You say you have access to heated buildings during the day, so it would make things a lot simpler for you if you don't have to deal with cooking and eating at your camp. Perparing food outside in the cold takes a lot longer than in a heated kitchen, severly limits what you can do, and may also risk predator encounters depending on what is around your area in the winter.

posted almost 12 years ago

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Olin Lathrop‭

1473 reputation 14 251 114 39

Even the temperatures around 0 C are real threat to life!

For -20 C you'll definitely need very good equipment. A sleeping bag with comfort temperatures around -20 C will cost much but without it you won't cope. But you must note, that 'sleeping' in tents in such low temperatures is often not real sleep, but overnighting.

If it matters if you sleep alone or with someone else - yes, definitely! Each person in tent warms up the air, it is much much warmer with 4 people than with 2, and sleeping single is a challenge. Also, if you get ill, 1 km in deep snow is much more exhausting than you could imagine.

My answer: you are risking your life. In team the risk can be really low, but I wouldn't risk such expedition alone if I were you, if you're not a survivalist.

posted almost 12 years ago

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Danubian Sailor‭

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I cannot answer directly if you are risking your life or not, however, it is quite possible to tent in -20C weather, given appropriate preparations and gear. Condensation, possible wind and snow-load are a few of the environmental factors to consider in your preparations and gear selection. The condensation one is critical, as damp gear (in general) loses significant heat retention value.

Presuming you are close enough to the city that wild animals are not a problem, you might still want to check the local area for what kind of animals are about in the winter.

Given that you have no winter camping experience, I would strongly suggest you try it out for a day or two first, perhaps somewhere closer to home, before you go. Winter camping is significantly different in some ways than summer. Cooking will take significantly longer. Even heating water can take a long time and burn quite a bit of whatever fuel you plan to use. You will unavoidably have to remove heavy gloves to do certain tasks, and your hands will invariably get quite cold. The rest of you can be more-or-less well insulated - but you'll have to have quit a few layers and changes of clothing to be comfortable/dry.

I would further suggest some kind of check-in system, that someone knows where you are to be every morning, and comes looking if you don't show up to class. If for whatever reason you are caught out, the sooner someone starts looking, the better off you'll be.

Remember too, any electronics or similar kit may not work at those temperatures, and if they do, the battery life may well be significantly worse.

So by all means, prepare well and then try something new, but perhaps with a few days of a test run first.

posted almost 12 years ago

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sdg‭

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