Can a Loud Noise Really Cause an Avalanche?

Anyone who has spent time watching action movies has seen the heart-pounding moment when a loud noise -- a gunshot or a woman's shriek, for example -- sends a shock wave into a mountainside, triggering a life-threatening avalanche. The truth is, no matter how loudly you yodel, scream, or shout, you can't move a mountainside. Slab avalanches actually occur when a fragile sheet of snow gets covered by a more compact one, and then a vibration causes the whole thing to collapse. To force an avalanche, snow safety teams use dynamite to create the vibration they need. Researchers have tried to get the same results from loud sounds, including using a bullhorn, but eventually they had to pack it in -- the snow didn't budge. According to the Utah Avalanche Center, even low-altitude airplane flights and sonic booms can't shake things up enough to cause an avalanche.

What you don't know about snow:

• In 1988, scientist Nancy Knight used a microscope to prove that two snowflakes really can be identical.
• Syracuse, New York, made snow "illegal" in 1991 after getting hit with 162.5 inches (4.1 m) that winter; an additional two inches (5 cm) fell two days later.
• In March 2015, a whopping 100 inches (2.5 m) of snow fell on Capracotta, Italy, in only 18 hours.