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Mapping Utah Avalanches

There are many variables that come into play regarding avalanches. But, for the purpose of this website, I will limit my explanation to the most obvious factors. First, slope angles, generally, must be greater than 30 degrees in order for an avalanche to occur. And the higher degree of slope angle, the more likely it becomes that an avalanche will occur if other variables are present. The second variable is the snowpack. The snowpack is the most indicative variable of avalanche hazard. The snowpack is dependent on many factors like precipitation, wind, and temperature flux, all of which are beyond the scope of my education, and are also affected by slope aspect. In summation, in order for a slope to slide, the slope angle needs to be around 30 degrees, there must be at least one unstable layer in the snowpack and all the weather variables also increase the likelyhood of a slide happenning on a slope of 30 degrees with a weak layer of snow present. So, if those factors are present, be aware and be safe.

For more information on the science of avalanches, please click here for my links page.

Slab avalanches: Slab avalanches occur when a more cohesive or harder layer of snow sets on top of a less cohesive or softer and weaker layer of snow.  When the less cohesive and weaker layer is disturbed, the layers of snow above that will start to slide. Slab avalanches are often large, voluminous and flow downslope with ferocity and momentum. Most people that die in avalanches, die in slab avalanches.

Sluffs or loose snow avalanches: Sluffs are powdery and cold surface layer avalanches. These are often the most forgiving avalanches but they too can be dangerous when exposure is high.

Wet avalanches: Wet avalanches occur when warm temperatures melt the surface snow layers and saturate them with water.  The water weakens the bonds between layers and avalanches often occur. Wet avalanches move at a slower pace but due to the wet cement like character, they tend to be very dangerous if caught. 

The following link is an avalanche safety tutorial- http://www.avalanche.org/tutorial/tutorial.html

 

The following videos explain the most popular avalanche safety tests for backcountry travellers:

Compression Test Video (provided by fsavalanche.org)

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Rutschblock Test Video (provided by fsavalanche.org)

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