Avalanches are not random events, but the result of delicate instability in snow layers. We analyze the types of avalanches, the "insidious" conditions that cause them—such as temperature gradients and wind—and provide a detailed guide on how to react if you get trapped. From using an avalanche airbag to creating vital oxygen space, this article is essential for every mountain enthusiast.
Understanding Avalanche Formation
Avalanches occur when the stress on a snow layer exceeds its strength. This delicate balance can be disrupted by various factors, including new snowfall, temperature changes, wind loading, and human triggers. Understanding these mechanics is crucial for backcountry safety.
Types of Avalanches
Slab Avalanches
The most dangerous type, slab avalanches occur when a cohesive layer of snow breaks away and slides down the slope. They account for most avalanche fatalities and can be triggered by skiers or snowboarders.
Loose Snow Avalanches
Also called "sluffs," these start from a single point and fan out as they descend. They're typically less dangerous but can push victims over cliffs or into obstacles.
Wet Avalanches
Occurring during warm periods, wet avalanches move slower but carry tremendous force due to their heavy, dense snow. They can destroy buildings and infrastructure.
Danger Signs to Watch
- Recent heavy snowfall (30+ cm in 24 hours)
- "Whumpfing" sounds when walking on snow
- Shooting cracks in the snowpack
- Recent avalanche activity nearby
- Rapid temperature rise
Survival Equipment
Essential gear includes an avalanche transceiver (beacon), probe, and shovel. Consider an avalanche airbag backpack, which can help you stay on the surface during a slide.
If Caught in an Avalanche
- Try to escape to the side
- Deploy airbag if equipped
- Discard poles and try to "swim" to stay on top
- As snow slows, create an air pocket near your face
- Once stopped, try to determine which way is up
- Conserve air and wait for rescue
Companion Rescue
Most avalanche victims who survive are rescued by companions within 15 minutes. Practice with your transceiver regularly and take an avalanche safety course before venturing into backcountry terrain.
