Permafrost
About 20% of Earth's surface is covered by permafrost, land that is frozen year-round. Permafrost occurs at high latitudes or at very high altitudes—anywhere the mean annual s...
Read more
Permafrost
Permafrost is any ground, either of rock or soil, which is perennially frozen. Continuous permafrost refers to areas which have a continuous layer of permafrost. Discontinuous permafrost oc...
Read more
Permafrost
Permafrost