Construction of adequate temporary shelter in snow conditions.

This is a specific technical knowledge.

A snow shelter, properly constructed, can maintain an interior temperature significantly above the outside temperature because of snow’s insulating properties.

The specific techniques for constructing such shelter — the entry tunnel that prevents cold air from dropping directly into the living space, the smooth interior surfaces that prevent dripping as body heat causes the ceiling to melt slightly and refreeze, the ventilation considerations that prevent carbon dioxide buildup — are not intuitive.

They are taught.