Vail Daily column: Be prepared when you’re out in the cold
Vail, CO Colorado
“The mountains are just as cold and lonely tonight as they were 100 years ago. Don’t ski alone.”
This is the warning from ski resorts across the country. The tragic death of the snowboarder in Lake Tahoe over the holidays was a sad reminder of this fact – despite the lift towers, lodges, and highly trained ski patrollers, mountains are still risky places. Our mountains are fun to play in if you are dressed right and prepared. Snow and cold, however, can be dangerous for those caught unaware. Hypothermia is one of the key dangers resulting from overexposure to cold, and it can be deadly.
Most people associate hypothermia with exposure to extremely cold temperatures, but it can develop anytime the surrounding temperature is lower than normal body temperature. Hypothermia develops when a person loses heat faster than they produce it. Our bodies produce heat from metabolism, or the burning of food molecules using inhaled oxygen. When our bodies move, heat production from skeletal muscles can increase as much as 10 times compared to the resting rate. Shivering alone can help the body increase its heat production by five times. As long as our bodies are moving and producing more heat than we are losing to the environment, we stay warm and cozy.
As a species, human beings are not well adapted to the cold, at least not physically. With our big heads, sparse fur, and long thin limbs, we are almost constantly transferring heat to our environment. Starting with our big head to body ratio, which is even bigger in children, our heads are a tremendous source of heat loss, responsible for about half of the total heat radiated to the environment. Wear an insulated hat (or helmet) and keep body surfaces covered to reduce heat loss from radiation.
We also lose heat through conduction, or direct contact with cold surfaces. Everyone who has sat on a cold ski lift seat has felt the sensation of heat being sucked out through their backside – slowed significantly by insulated ski pants and padded lift seats.
Perhaps the biggest source of heat loss is from convection. Convective heat loss occurs when our bodies are immersed in moving fluids, like air or water, that have a temperature less than that of our bodies. Imagine standing outside on a windy day. Your body is constantly radiating heat, warming the air directly in contact with you. The wind then blows these molecules away, replacing them with new, cold molecules that your body must warm again. In water, the process is even more dramatic, as a body immersed in cold water loses heat at a very rapid rate. The end result of all this heat loss can be the lowering of body temperature known as hypothermia.
Hypothermia is a serious condition and requires emergency treatment. Symptoms of hypothermia include uncontrolled shivering (initially), clumsiness, drowsiness, confusion, apathy, and eventually, a weak pulse and shallow breathing. Patients with suspected hypothermia should be treated gently, as sudden or vigorous movement can cause cardiac arrest. Warming should occur gradually, and should start with a slow warming of the body core. Heat applied to the limbs can cause cold blood to go directly to the body’s core, which can be fatal. Bring patients indoors if possible, and seek professional medical help for suspected hypothermia patients.
The best cure for hypothermia is an ounce of prevention. It’s important to plan ahead, dress carefully, and always go out with a buddy. Know the signs and symptoms that indicate danger, and have a backup plan for emergencies. We can also follow the wise advice from Peter Marchand, author of “Life in the Cold,” who tells us that the Inuit people of the north say that the best way to handle the cold weather is to “take care not to be cold.”
Safe travels, everyone.
Jaymee Squires is the director of graduate studies at Walking Mountains Science Center. She especially loves to play outside when the sun is shining and the temperature is above freezing.