"By the look of this snow debris, my guess is that we just experienced an avalanche, otherwise known as 'The White Death'. These things are deadly since they carry a huge force and can travel faster than 150km/h. In fact, 150 people around the world die from avalanches each year. An avalanche tends to occur when snow on the surface is too heavy or weak that it can't hold onto the slope, so it slides downhill. Usually this isn't caused by a scream or a loud noise, but rather by the pressure of something against the snow, like the weight of a person's step. So yell all you want, but watch where you step!"