The mosses that form on the surface impede drainage and permafrost areas develop marsh and tundra characteristics. Permafrost's Impact on Military Training. Permafrost lies below the active layer, or depth of the summer thaw, and extends several feet thick in the Arctic. Depths of permafrost are variable even within short distances in the discontinuous and sporadic permafrost zones. Depths of permafrost are depend upon exposure, ground cover, soil characteristics, and other factors.
Examples below reflect the average depth of perma frost encountered.
Permafrost, or permanently frozen ground is of great importance in the engineering and design of pipelines, roads, railroads, and training ranges and usages. The frozen ground forms an extremely strong and stable foundation material if it is kept in a frozen state. However, if the permafrost is allowed to thaw, the soil becomes extremely weak and foundation failures are very common. Training ranges can be utilized during winter while frozen, or restrict the continuous permafrost area from training utilization during summer months. Fort Wainwright and Greely are underlain by discontinuous and continuous permafrost.