Heat and Cold


What is permafrost?

Permafrost refers to soil that is frozen all year long, even during the summer, for two consecutive years or more. Such conditions occur in areas where the mean annual temperature is 23°F (–5°C) or less. Construction in polar regions where permafrost is found can be problematic, because sometimes the ground can thaw beneath a building that was constructed over frozen ground; when this happens, building foundations are easily compromised.


This is a web preview of the "The Handy Weather Answer Book" app. Many features only work on your mobile device. If you like what you see, we hope you will consider buying. Get the App