Every winter backcountry enthusiast should be well-versed in how to identify, prevent and respond to avalanches. Often avalanches can be prevented if you follow simple guidelines. At SOLE, we recommend that anyone participating in winter recreation should consider taking a formal avalanche certification workshop. Led by professionals in the field, participants will not only gain insight into how to recognize probable avalanche conditions they will be able to apply technical skills if they find one of their party caught in the midst of this natural beast.
Most avalanches are triggered by a human traveling across the unstable terrain. Once an avalanche is triggered and an individual is burried they have only a 27% chance of survival after 35 minutes. This is why understanding how to prevent an avalanche and how to react once one is triggered is so crucial. Therefore, individuals should look for potential avalanche danger and be prepared to respond if they find themselves or someone else in a dire circumstance.
Some important considerations to look for include:
- Recent avalanche activity
- Recent heavy wet snow or rain particularly on top of an already unstable snow pack
- Wind blown snow on leeward slopes
- Rapid warming and increasing temps
- A "whumpfing sound" coming from underneath as you travel
- Snow fractures occurring on the surface of the snow
- Snow collapsing underneath as you travel across
- Consistent weak snow layers even when there are no other warning signs
Another helpful tool is understanding the terrain you are traveling on. Some considerations regarding terrain include:
- Slope angle. Most avalanches occur on slopes ranging from 35-50 degrees. However slopes 30 degrees can slide as well.
- Steep slopes above a less step area. Even though you may be wanting to play on terrain less step you may still be prone to becoming caught in an avalanche if you are exposed to steep terrain above.
- Terrain traps. Anything that increases the likelihood that you may be caught in an avalanche, including, a run-out, flat transition above a steep slope, cliff bands and trees on a steep slope above.
- Trigger points. Avalanches can be triggered in specific points, along ridges or even flat transitions below steeper sections. Special considerations should be taken in areas including those with, wind deposits, rock outcroppings, low trees buried in the snow.
- Slope aspect. Ask yourself some simple questions to determine if the area is prone to avalanches. Does the slope face the sun or is it in the shade? Which direction does the slope face? Is their cornices that have built up on the ridges above?
- Have your party spread out.
- Have one person travel at a time across a slope in question.
- Avoid stopping near in potential run-outs or other terrain traps.
- Never descend directly above or near the group.
- Stay alert to changing conditions (see "red flags" listed above).
- Keep open communication with your group members.
- Be prepared to respond if someone triggers an avalanche.
Important basic items to consider, include:
- Avalanche beacon with new batteries and extra batteries
- Metal snow shovel
- Probe pole
- Compass (to determine direction slope is facing)
- Inclinometer (to determine slope angle)
- Good expedition first aid kit
- Gear to stay out overnight if needed
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