Avalanches

In fiction, many people cause an avalanche with shouts.
It really can’t be done, beyond the shadow of a doubt.
Our strongest voices offer maybe two pascals of pressure,
At least a hundred times too small for causes we can measure.
In theory, it could happen with a supersonic boom,
But that has never been confirmed. Some scientists assume
That avalanches triggered by a lower-flying jet
Respond to wind or shock waves more than sound (we don’t know yet).
They happen far more often with a snowmobile or skis,
So when you’re on a snowy peak, proceed with caution please.