There are plenty of cold-weather survival scenarios. You might be an avid camper or hiker lost in the dead of winter. You could be the victim of a plane crash in the Swiss Alps. Maybe you've had a car accident going over the river and through the woods to grandmother's house. Or perhaps you've simply lost electricity for an extended period of time in your own home. Knowing some basic tips and tricks can help make a difference in your comfort level, and even whether or not you make it through the night.
Nearly 50 percent of the Northern Hemisphere's total landmass can be classified as a cold region at some point in the year [source: Discovery Channel]. Ocean currents, elevation and wind all have an impact on how frigid it gets. Within these regions there are two subclassifications -- wet cold weather and dry cold weather. Wet cold describes conditions where the average temperature over a 24-hour period is 50 degrees Fahrenheit. This typically means that there are freezing conditions at night followed by thawing temperatures the following day. Dry cold means that the average daily temperature is below 14 degrees. In dry cold conditions, there is no thaw.
The other thing that's factored in with cold weather is wind chill -- the effect of moving air on exposed skin. Antarctic explorer Paul Siple coined the term "wind chill factor" in the late 1930s to help describe the effect that wind has on heat loss. He experimented by timing how long it took to freeze water in varying degrees of wind strength [source: USA Today]. In layman's terms, wind chill is described as how cold it "feels."
Cold weather has a dramatic effect on human health. According to a University of California, Berkeley economist, deaths related to cold reduce the average life expectancy of Americans by a decade, if not more [source: UC Berkeley News]. Cold weather also indirectly causes fatalities through accidents due to snow and ice, carbon monoxide poisoning and house fires. The elderly and the infirm are most susceptible to cold weather illness and injury, although the same UC Berkeley study reports that women make up two-thirds of the deaths after a cold spell.
In this article, we'll go into more detail about the effect cold weather has on humans. We'll also go over the basics of surviving freezing weather conditions -- from building a snow shelter in the wild to simple tips for the average homeowner.
Frostbite and Hypothermia
The two main cold-weather illnesses are frostbite and hypothermia. Frostbite means that your skin has fallen below the freezing point, and ice crystals are forming within your skin cells, killing them. If you're able to warm your skin, it will form a blister, change from blue to black in color and harden into a shell. This shell will eventually fall off to expose new skin underneath if the damage isn't too severe. This is the very painful "superficial" frostbite. Severe frostbite penetrates all the way to the muscle and bone and is characterized by tingling of extremities and changes in your skin's color and texture. The stages of frostbite are:
- Red skin - initial stage
- White skin - middle stage
- Hard skin - getting severe
- Blisters - severe
- Blackened skin - advanced stage
Severe frostbite usually causes tissue damage, and can even lead to amputation of fingers, toes, hands and feet. It's vital when afflicted with frostbite to warm your skin gradually. Cover your ears and put your fingers under your arms. Don't ever rub the damaged skin or submerge it in hot water -- you'll cause even more damage. Water between 100 and 106 degrees Fahrenheit is ideal to use as a warming agent. If you can, get into a warmer area immediately, even if it's just a tent or shelter. Remove any tight clothing that may restrict blood flow. You can put gauze or cloth between your fingers and toes to soak up moisture and prevent them from sticking together. It also helps to slightly elevate the affected area to reduce swelling.
Hypothermia is when your body loses more heat than it produces and your core body temperature drops. Some of the symptoms of hypothermia are:
- Slurred speech
- Stiff joints
- Loss of coordination
- Slow pulse
- Uncontrollable shivering
- Loss of bladder control
- Puffy face
- Mental confusion
Many times, getting wet in addition to the cold leads to hypothermia, and the result can be as severe as coma or death. To combat hypothermia, get yourself into a warmer environment as soon as possible. Cover with any items you can find -- blankets, sleeping bag, pillows or even newspaper. Most heat is lost through your head, so cover yours immediately if it's not already. If you have on wet clothing, take it off and replace it with some dry duds. If you have no dry clothing, it's better to strip naked than to wear something wet. You should always handle hypothermia victims carefully, as it's easy for them to go into cardiac arrest. Keep them horizontal and calm -- reassure them that they're going to be fine. If you're with someone, get into a sleeping bag together or simply hug each other tight to create warmth. If you're not trapped in the wilderness, seek professional medical attention as soon as possible.
In the next section, we'll look at how your shelter plays a part in cold weather survival.
A good shelter is the first thing you need to survive the freezing cold. Choosing your shelter's location is extremely important. Don't be lured in by clearings in the mountains -- they can be prime spots for avalanches. Check for accumulated debris and broken tree stumps at the base of the clearing. If you find both, chances are you're in an avalanche chute. The side of the clearing is a much better shelter location. You should also avoid areas near overlooks and cliffs.
If night is falling fast, you need to build an emergency shelter as soon as possible. Don't get too fancy -- your goal is to make it through the night. Dig a snow trench deep enough to provide a wind break. Pile and pack additional snow on the windy side for further protection. Get as much soft material as you can to line the bottom for insulation -- pine boughs are plentiful in most wooded areas. Once in, cover yourself with copious amounts of pine or any other leaves you can get. Snow is a better insulator than your average tent, so your emergency shelter should get you through the night.
If you have the time, build a more elaborate snow cave. Not only will it provide better protection from the elements, but constructing it will get your heart rate going and warm you up. Just make sure you don't sweat -- moisture is your enemy in the freezing cold. Hillsides provide good wind shelter and low-lying areas are colder and more damp. Make your shelter as small as possible to help retain heat. This is especially true for the entrance, which should be blocked with a backpack or stacked up tree branches.
It's also important to ventilate your shelter. Poke small air holes in the ceiling with tree branches and make sure your blocked entrance allows enough airflow. If you have a cooking stove or lantern, avoid using it inside unless the shelter is extremely well ventilated. It's best to not risk it at all -- carbon monoxide poisoning is a killer in the woods and sneaks up on you fast. Avoid using metal like a plane wing or found tin roofing to aid your shelter -- it will suck up the heat you need.
When you're trapped in the cold and there is no snow, build a debris hut:
- Place a ridgepole, the pole that runs the length of the shelter, with one end on the ground and the other on top of a sturdy base like a tree stump or boulder. You can also lash it to a tree.
- Take two more thick branches and place them diagonally at the top of the ridgepole and lash them together with vine or rope.
- Use thick branches to line the length of the ridgepole to create the ribbed frame. Make sure it's wide enough to accommodate you.
- Place smaller sticks crosswise to make a lattice effect.
- Add lighter soft debris like pine needles and leaves until it's at least two feet thick -- the thicker the debris, the more protection it offers.
- Cover the interior floor with pine and leaves and block the entrance with a rock or more debris.
These are just a couple of examples of wilderness shelters. More can be found in How to Build a Shelter. In the next section, we'll look at how water and your choice of clothing can help you survive the freezing cold.
Water and Clothing
Once you've built your shelter, you should focus on water and warmth. The human body can survive for about a week or less without water, depending on conditions. Dehydration can set in within a few hours [source: EPA]. It's important to remember that water is just as important in cold weather survival as it is in hot weather. A minimum of two quarts of water is needed for survival and in cold conditions, you should drink even more [source: Wilderness Survival].
Eating snow may seem like a great idea, but it will lower your core temperature and actually bring on dehydration. Melt your ice and snow in a container if you have one. If not, wrap it in cloth and suck the water out as it melts. It's also important to purify the water by boiling it for 10 minutes whenever possible. Snow and ice in remote locations can be safe to ingest, but it's always a risk. Avoid drinking coffee or alcohol if you have them on hand. It may give you a short term warm-up, but it'll dehydrate you quickly. Try to find open water -- rivers, streams, lakes and springs. If you have no means to purify, get your water from a fast-moving body and strain it with some cloth to remove large bits of sediment. You can read more about collecting water in How to Find Water in the Wild.
Warmth is the next step in your bid to survive the freezing cold. Almost everyone knows that layered clothing is important to stay warm. Use the C.O.L.D. acronym to help you remember these important tips:
- C - Clean: Keep your layers clean. Dirt and sweat can mat down air spaces, reducing your clothes' warmth.
- O - Overheating: Sweating dampens your skin and clothes, which leads to further chill. Avoid overheating by adjusting your layers accordingly.
- L - Loose Layers: Blood flow is essential to staying warm. Tight-fitting clothing can restrict your circulation.
- D - Dry: Wet clothing is your enemy in the cold. Avoid absorbent cotton fabrics and keep your neck area loose to allow moisture to escape.
Just as you layer your clothing, you should also layer what you have on your feet. Try a thin pair of nylon, silk or wool socks for starters -- then layer with additional wool socks. Keep your feet dry, even if it means taking off your socks temporarily to do so. Mittens are warmer than gloves because your fingers come into direct contact with each other.
While it is a myth that most of your body heat leaves through your head, you still want your head covered for protection against the elements. Get a stocking cap that covers your ears and don't take it off unless you start to sweat. Even a baseball cap can help retain heat. Your parka should ideally be waterproof and lined with goose down or some other fibrous filling. Make sure it's large enough to fit comfortably over your layers and is well ventilated.
Your sleepwear should never be the clothes you wore that day -- chances are they're damp. The best thing to sleep in is some kind of thermal underwear or sweats. Avoid wearing these items during the day to ensure you have something warm and dry to sleep in. Wear your driest socks and keep your hat on. Even though it may feel warmer, don't sleep with your head and face inside your sleeping bag. Your hot breath becomes moist and adds dampness.
In the next section, we'll look at how fire is crucial to your freezing cold survival.
Once you have your shelter and water, get a fire going. In addition to keeping you warm, fire can be used to melt snow for water, cook food, dry out clothing and create smoke for rescue. You can read about emergency fire starting techniques in How to Start a Fire Without a Match, but for now let's assume you have the necessary equipment -- either matches or a lighter. Dig a fire pit near your shelter's entrance with a good wind break piled around it. The fire should be in the center, with room for your wood and a place to sit.
After you dig your pit, start collecting your fuel. You'll need a tinder starter, small to medium kindling and larger branches and logs -- make sure you have a wide range of sizes. If it's dry, you can use any brown leaf, pine straw or bark for the starter. If it's wet, peel bark away from trees and use your knife to get fine shavings from the trunk. Dry wood can be found under thick trees. As for how much, a good rule of thumb is to collect as much wood as you think you'll need, and then double that amount.
Once you've dug the pit and collected enough wood, you're ready to build your fire. There are two basic versions that work well -- the tepee and the log cabin. For a tepee fire:
- Stack medium-sized branches in the pit side by side for your base.
- Place your tinder on the center of the base.
- Get a medium-sized forked branch and a straight branch of like size.
- Rest the straight piece in the fork and add additional pieces around it, meeting at the center to form a solid tepee frame.
- Add smaller kindling until it's fairly dense, while allowing air to pass through.
- Light your tinder and gently blow until it's well lit.
- The smaller kindling around your tepee will ignite, while the heavier frame pieces stay in place.
Once the fire is burning strong, the tepee frame will light and fall. At this point, start adding your larger pieces of fuel.
For a log cabin-style fire:
- Place two medium-sized branches parallel to each other, about 18 inches apart.
- Stack two more like-sized branches on top to form a square.
- Keep doing this until you have a "log cabin" about a foot high.
- Place some branches inside the cabin on the bottom for your base.
- Put your tinder on top of the base and light it.
- Add small kindling to the tinder until it's well-lit.
Your cabin frame will get hotter and hotter until it ignites, leaving you a hot base of coals to add your larger branches and logs. Once your fire is going strong, build another outer frame to dry wet logs.
Some other fire tips:
- Add chapstick, petroleum jelly or insect repellent to make your tinder burn hotter and longer.
- Break apart dry animal dung to use as tinder or kindling.
- Place large rocks around the fire to contain flames.
- Push hot rocks into your shelter for additional warmth.
- Use your fire as your entrance blockade -- just make sure the smoke stays out.
- Keep your fire going after it's lit.
- Feed your fire slowly.
In the next section, we'll look at some tips for surviving freezing weather in your home during power outages.
Surviving in Your Home
Not every cold-weather survival scenario involves being in the middle of nowhere. If you live in a frigid area and rely on electricity for your heat, you might find yourself freezing in your own home. Winter power outages can be scary situations for the young, elderly and infirm. Wintertime road travelers should also take extra care in planning their journeys.
If you live in an area that gets severe weather in the wintertime, you should have a gas-powered heater on hand in case of a power outage. Kerosene heaters are fairly inexpensive and easy to operate. Pick one that's wide and has a low center of gravity. This makes it difficult for you or a pet to knock it over. You should also avoid using flammable solvents and sprays near the open-flame heater.
No matter how cold you get, never use your gas oven as means to warm your home -- the same goes for gas clothes dryers. Carbon monoxide poisoning is a serious threat and hard to detect -- the gas is odorless and colorless. It can lead to nausea, headaches, coma and even death. Invest in a carbon monoxide detector. Many smoke detectors also sniff out carbon monoxide. Have your furnace checked once a year to make sure there's no buildup of carbon monoxide in the system.
If you have a fireplace, use it as your main heat source. Sleep in the room with the fireplace if possible. It's not a bad idea to make sure you have a nice stockpile of wood -- some outages can last weeks. You need to make sure your chimney is clear and clean and always use a fire screen to keep hot embers where they belong. If you're suffering from a power loss and you have no gas heater or fireplace, the same clothing principles as outdoor survival should be used. Layer your clothing well, put on several pairs of socks and always wear a hat. If you have a sleeping bag, put it under the covers of your bed and sleep in it at night. If you get a deep snow, only shovel it if you're in pretty good physical shape -- you could have a heart attack and end up freezing to death in your own driveway.
If you're traveling in wintry conditions, think ahead and put some blankets or a sleeping bag in your trunk. Always keep some waterproof matches or a lighter in your glove box, and if you get stranded and go for help, don't forget to take them with you. You should also have a map of the area you're traveling through, even if you know it well. Blizzards can disorient you, and a good map can be the difference between life and death. You should also let someone know when and where you're going, and pack an emergency kit for the trip. Aside from blankets and matches, a first-aid kit, a gallon jug of water and some energy bars or chocolate can come in handy.
If you want to read more about surviving extreme conditions, you can look into the articles on the following page.
- How to Build a Shelter
- How to Find Water in the Wild
- Harrowing Survival Stories
- How the Army Rangers Work
- How Fire Works
- How Food Works
- How Water Works
- How does the windchill factor work?
- Why do bridges ice before the rest of the highway?
- Why do they use salt to melt ice on the road in winter?
- Why is it colder at the top of a mountain than it is at sea level?
- Why is snow white?
More Great Links
- "Basic Principles of Cold Weather Survival." wilderness-survival.net, 2007. http://www.wilderness-survival.net/cold-3.php
- "Cold Weather Survival." The Discovery Channel, 2007. http://dsc.discovery.com/convergence/survival/guide/environment/cold/cold.html
- Davis, Jeanie Lerche. "Cold Weather Survival 101." WebMD.com, 2007. http://www.webmd.com/content/Article/29/1728_68023.htm
- "Formula used to calculate wind chill." USA Today, October 30, 2001. http://www.usatoday.com/weather/resources/basics/windchill/wind-chill-formulas.htm
- Maclay, Kathleen. "Economist examines costs of extreme cold weather." UC Berkeley News. Dec. 19, 2007. http://www.berkeley.edu/news/media/releases/2007/12/19_cold.shtml
- Montague, Arthur. "Winter Survival Skills." Conscious Choice, 2002. http://www.consciouschoice.com/2002/cc1501/wintersurvival1501.html
- "Surviving the Cold Weather." National Safety Council, 2007. http://www.nsc.org/library/facts/cold.htm
- "Survival, Evasion, and Recovery." U.S. Military Field Manual 21-76-1, June 1999.
- Teague, Leanna. "How to Survive in Freezing Cold Weather." Associated Content, February 10, 2007. http://www.associatedcontent.com/article/140156/how_to_survive_in_freezing_cold_weather.html
- "Water Trivia Facts." epa.gov, 2008. http://www.epa.gov/SAFEWATER/kids/water_trivia_facts.html