Sublime

The sub-zero temperatures quickly freeze the water into the conical structure, so that a mass of ice begins to grow. The end result has the same high, narrow dome-shape typical of Buddhist shrines, hence the “stupa” part of the name, which slows down subsequent melting because the surface area exposed to the sun and warm temperatures is minimised.

This can happen at a subtle level (slight holding of the breath, and stillness) and at a gross level (literally being unable to speak or act, and often dissociating within the freeze response).