Often the site of mounds called pingos, it is formed by a process known as pergelation.
A patch of it is unexpectedly found in the crater of Mauna Kea at an elevation of over 13,000 feet, and the Russian term "talik" describes regions that lie above it but below the active layer. Often the site of mounds called pingos, it is formed by a process known as pergelation. Estimated to comprise around twenty percent of the world's land surface, it can maintain its integrity if it is composed of well-drained, coarse-grained sediments as opposed to finer-grained soil with lots of ice. Mostly located at latitudes greater than 60 degrees, for 10 points, what is the term for ground that is kept below 0 Celsius for a period of at least two years?
A patch of it is unexpectedly found in the crater of Mauna Kea at an elevation of over 13,000 feet, and the Russian term "talik" describes regions that lie above it but below the active layer.
{permafrost} [begrudgingly accept {permanently frozen ground} before “ground”]