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The most Common Types of Avalanches and their causes



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Avalanches can be the worst nightmare of anybody on a mountain, or below it for that matter.  When observing avalanches, if that’s even possible, you might notice a couple of differences in many of the ways that they form and why they are caused.  Remember, all avalanches are extremely dangerous, and one should not be taken more lightly than another.

 In general, there are three major types of avalanches, all of which are extremely dangerous to anybody near the mountain it forms on.  The first type is the Slab Avalanche.  The Slab Avalanche is the leading killer of people that are in avalanches.  The movies that portray horrible accidents on mountains, or even pioneering catastrophes are painting a vivid picture of the very destructive Slab Avalanche.  Slab Avalanches occur when a more cohesive or harder layer of snow sets on top of a less cohesive layer or softer and weaker layer of snow.  Sometimes the weak layer can hardly support the stronger layer that is resting atop of it.  When additional weight comes over the layers, say for instance a skier, the layers collapse and the snowpack fractures; thus resulting in the deadly Slab Avalanche.

The second most common type of avalanches are the: Sluffs or loose slow avalanches.  The word sluff is important to define here, and the definition is a cold, powdery surface slide that typically is a less dangerous type of slide.  While these avalanches might be considered “less dangerous” it is still important to remember that all types of slides are dangerous.  You can ski or board next to these avalanches, but if you were to get in their way, it would pretty much ruin your skiing or boarding experience. 

The third most common type of avalanche is called a “Wet avalanches”.  Wet avalanches, or wet slides, 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 tend to move more slowly than their counterparts, but can still be destructive if you get caught in their path.  Factors that influence wet avalanches include: if temperatures have been above freezing for an extended period of time wet avalanches are more likely to occur than normal. If you are sinking up to your knees or higher while you are riding a snowboard or skiing, than a wet avalanche is likely to occur (if said snow is wet).  Lastly, you can see if snow is “wet” snow by grabbing a handful of snow with your glove (I don’t advise grabbing it with your bare hand) and it makes your glove wet, or more severely: water is literally coming out of your handful of snow; than a wet avalanche is bound to happen if you continue to ski/board on the area.

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