Cold weather survival is as much a mental challenge as a physical one. As extreme cold saps your will and makes it more difficult to think clearly and act decisively, careful planning and having the proper gear can be the difference between life and death. Ideally, you'll have a radio or a buddy along to help keep your mind occupied and clear. But those won't guarantee your survival. In addition to the gear you'd bring on any other trip, a few cold weather essentials should also be in your pack.
Dressing in loose layers is essential to cold weather survival. When choosing clothes, synthetic fibers are preferable to cotton, which absorbs more moisture. Having multiple layers keeps pockets of warm air close to your body, providing natural insulation. Wear only dry clothes, though, and remove excess layers if necessary to avoid sweating during physical exertion. Don't neglect to include your legs when you're planning your layers. Any type of hat will also increase your ability to retain heat and, if the had does not cover your ears, a scarf or balaclava will improve coverage and insulation. Gloves, knee-high socks and waterproof footwear are also essential. Nearly half your body heat can be lost through your uncovered head, and the heat lost through your uncovered neck, ankles and wrists is significant as well.
A sleeping bag rated to 20 degrees Fahrenheit or lower is an important piece of gear for cold weather survival situations. A foam mat gets your body off the cold ground or snow and prevents heat loss while you sleep. Keep your sleeping bag dry when not in use by packing it in a watertight bag or rolling it as tightly as possible. Do not wear wet clothing in the sleeping bag, and keep your head outside the bag so your breath does not condense near your body.
Cold weather survival requires a high-calorie intake to maintain adequate body heat. Foods high in carbohydrates with sufficient protein, combined with enough physical activity to keep your metabolism up, are crucial to making it through cold weather. Trail mixes and granola bars generally have a balanced mix of carbohydrates and protein, but avoid overly sugary foods unless they're needed to stimulate blood flow during treatment of hypothermia. Also avoid food or beverages that can dehydrate you, like meat, chocolate, coffee and alcohol. Drink at least two quarts of water every day.
First Aid and Other Gear
In addition to having a basic first aid kid with gauze, ointment, scissors, a fishing kit, a reflective mirror and tweezers, you should be able to recognize the onset of health complications related to cold weather. Hypothermia can occur in temperatures above freezing. It begins with shivering but progresses to slurred speech, lack of coordination, poor decision-making, weak pulse and loss of consciousness. It should be treated by removing any wet clothing, getting warm and eating high-energy food. Skin that is numb or burning or has changed color may be frostbitten. Gradually warm mildly frostbitten skin with warm water heated by a camping stove or fire. Be sure to bring a lighter, waterproof matches or a flint so that you'll be able to start a fire. Don't defrost severe frostbite without professional medical assistance.