Temperature Gradient Metamorphosis

The changes that occur to snow crystals over time in deep snowpacks, when the temperature at the surface of the snow is significantly colder than the temperature at the base of the snow for a period of time. This is most apparent when air temperatures are between 0 and -40 degrees Fahrenheit. Due to the insulating properties of snow, the base of a deep layer of snow will remain higher than the air temperature in these conditions.