15-95. You will face many obstacles if your survival situation is in an arctic or subarctic region. Your location and the time of the year will determine the types of obstacles and the inherent dangers. You should—
Avoid traveling during a blizzard.
Take care when crossing thin ice. Distribute your weight by lying flat and crawling.
Cross streams when the water level is lowest. Normal freezing and thawing action may cause a stream level to vary as much as 2 to 2.5 meters (7 to 8 feet) per day. This variance may occur any time during the day, depending on the distance from a glacier, the temperature, and the terrain. Consider this variation in water level when selecting a campsite near a stream.
Consider the clear arctic air. It makes estimating distance difficult. You more frequently underestimate than overestimate distances.
Avoid travel in "whiteout" conditions. The lack of contrasting colors makes it impossible to judge the nature of the terrain.
Always cross a snow bridge at right angles to the obstacle it crosses. Find the strongest part of the bridge by poking ahead of you with a pole or ice axe. Distribute your weight by crawling or by wearing snowshoes or skis.
Make camp early so that you have plenty of time to build a shelter.
Consider frozen or unfrozen rivers as avenues of travel. However, some rivers that appear frozen may have soft, open areas that make travel very difficult or may not allow walking, skiing, or sledding.
Use snowshoes if you are traveling over snow-covered terrain. Snow 30 or more centimeters (12 inches or more) deep makes traveling difficult. If you do not have snowshoes, make a pair using willow, strips of cloth, leather, or other suitable material.
15-96. It is almost impossible to travel in deep snow without snowshoes or skis. Traveling by foot leaves a well-marked trail for any pursuers to follow. If you must travel in deep snow, avoid snow-covered streams. The snow, which acts as an insulator, may have prevented ice from forming over the water. In hilly terrain, avoid areas where avalanches appear possible. Travel in the early morning in areas where there is danger of avalanches. On ridges, snow gathers on the lee side in overhanging piles called cornices. These often extend far out from the ridge and may break loose if stepped on.