Questions
What can trigger an avalanche?
What is the avalanche "danger zone"?
How are people working to prevent avalanches from harming others?
Why do you think skiing can trigger an avalanche, but a person yelling would not?
Fast Facts
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- Approximately 90% of avalanche incidents are triggered by a victim or someone with the victim.
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- Avalanches can reach speeds of approximately 129 kilometers per hour (80 miles per hour) within five seconds.
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- Avalanches are most common during and in the 24 hours after a storm dumps 30.5 centimeters (12 inches) or more of snow.
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- Although many people believe that avalanches occur without warning, there are many precursors. Avalanches actually begin several hours or days before the snowfall, because previous snowfalls may have already weakend the layers below.
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- If you are caught in an avalanche, it's best to try to "swim" to the surface.
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- If dug out within 15 minutes, about 93% of avalanche victims survive.
Vocabulary
| Term | Part of Speech | Definition | Encyclopedic Entry | |
|---|---|---|---|---|
| avalanche | noun | large mass of snow and other material suddenly and quickly tumbling down a mountain. |
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| sluff avalanche | noun | small slide of loose snow. |
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| slab avalanche | noun | dangerous slide of snow that falls as a large, flat whole (slab). |
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| slope | noun | slant, either upward or downward, from a straight or flat path. |
Writers
O'Shannon Burns
Editors
Christina Riska
Producers
Alison Michel
Sources
http://environment.nationalgeographic.com/environment/natural-disasters/avalanche-profile.html
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