As we begin December with record snowfalls in November, we face the dangers of an avalanche occurring. From winter enthusiasts trekking through the back country to motorist on the roads, we all need to be aware of one of nature's most dangerous calling cards.
All that is necessary for an avalanche to run is a slope. As temperatures warm the snow can lose its bond with the surface causing it to slide. For example, we have all noticed snow pack on a car windshield. The snow sticks to the surface while the temperatures remain cold, but when temperatures warm, the snow slides down the windshield in small slabs - a smaller version of an avalanche.
Mountain avalanches are much larger and more complex. A large avalanche may release 300,000 cubic yards of snow making it equivalent to 20 football fields filled with ten feet of snow. These large avalanches are often naturally released. Smaller avalanches are most dangerous to skiers and other winter enthusiasts. Walking or skiing across an already unstable area may cause an avalanche to occur.
An avalanche has three parts; the first is the starting zone. This is the area of the slope where the snow is most unstable and can fracture releasing it from the surrounding snow cover. The second is the avalanche track. This is the path an avalanche travels as it heads down hill. Look for large vertical paths of missing trees; this will often signal a re-current avalanche path. The third is the run out zone. This is the area where snow and other debris come to a stop at the bottom of the slope and is also an indicator of a frequent avalanche path.
Several factors can affect the likelihood of an avalanche occurring such as temperature and wind as well as slope steepness and snow pack conditions. These conditions change frequently, so a vigilant awareness of your surroundings is needed.
Avalanches often occur during a storm that deposits heavy amounts of snow or within the first 24 hours following it. Being aware of current weather conditions, as well as conditions from the previous couple of days, is important. If there has been heavy snowfall the day before your outing, you might want to postpone your trip to avoid the increase in avalanche danger.
When enjoying the outdoors or driving down the road, be aware of any cracks shooting across the snow pack as this can signal instability. If walking or skiing, and you hear a hollow thumping sound under the snow, this may indicate a weaker layer, leaving the surface more vulnerable to collapse.
So what can you do to prepare for an emergency such as an avalanche? If you are an outdoor enthusiast and trek the back country, always travel in groups and stay with the group. Investing in an avalanche beacon and taking it with you could be what saves your life if you are caught in an avalanche. Make sure it is on and set to transmit rather than to receive. Purchase a portable shovel made of plastic or aluminum. These are light weight and compact enough to carry in a backpack.
If you are caught in an avalanche use free-style swimming like motions, thrusting upward to try and stay near the top of the flow. When avalanches come to a stop and debris piles up, the snow can set as hard as cement within a matter of minutes. If you are not near the surface, try to maintain an air pocket in front of you by punching into the snow with your hands and arms. Try to preserve your air space. Snow is a great insulator, and rescuers will hear you until they are right on top of you. Stay calm and keep your breathing steady. If you are able to remain calm, your body will conserve energy better.
If driving and you need to travel through an avalanche zone, continue driving until you have reached a safety zone. These areas are well marked, and signs are posted for your protection. Carry a small shovel, food and water, as well as blankets and a portable radio in your vehicle during travel. You should also carry a first aid kit and tire chains.
If you live in a known avalanche area always be sure to have extra supplies of food and water and other essentials for your disaster preparedness kit such as flashlights with batteries and a portable radio.
While enjoying the snow this season remember to follow these simple safety tips and always be aware of the current conditions. For more information you may visit our web site at www.alaska.redcross.org or call the offices of your American Red Cross of Alaska at 463-5713.
About the American Red Cross of Alaska: Governed by volunteers and supported by community donations, the American Red Cross of Alaska is dedicated to saving lives and helping Alaskans prevent, prepare for and respond to emergencies. Led by over 1,500 volunteers and 27 employees, last year the American Red Cross of Alaska mobilized relief to over 1,050 Alaskans affected by disaster, trained over 32,000 people in lifesaving skills, taught over 78,500 Alaskans how to be better prepared for disasters, and exchanged more than 4,100 emergency messages for U.S. military service personnel and their families. For more information about the American Red Cross of Alaska, please visit our website at www.alaska.redcross.org.