Permafrost is ground that stays frozen year round and underlies most of the Park. It dramatically shapes the landscape by determining where plants grow, the flow of surface water, and ultimately where animals live. In the summer, the upper foot or two of ground thaws; this is known as the active layer. However, because the ground beneath the active layer stays frozen, water collects on top of flat ground instead of draining away. There are many boggy areas, wetlands, and small lakes in the arctic landscape, in spite of the fact that most lowlands receive just 10 to 20 inches of rain and snow per year - less than most places in the eastern and midwestern United States.
Thawing of permafrost has many consequences, such as drainage of lakes, soil erosion, changing river patterns, increased sedimentation of streams and lakes, and changes in vegetation. All of these consequences can considerably affect how humans move across the landscape and the availability of wildlife and other food sources.
Permafrost monitoring involves looking at long-term changes in permafrost extent and temperature, active layer depth, and permafrost-related landforms. Results of this monitoring will help us understand broad changes in ecosystems that could occur as a result of climate change, such as changes in the area of ponds and lakes, the turbidity of streams, and the density of vegetation. Permafrost is a "Vital Sign" for the Arctic Network Inventory and Monitoring Program (ARCN).
Information gathered from this monitoring effort will be used to:
Permafrost - Its all over the place. Discover how to know it when you see it.
Pingos - Sounds like an exotic dessert. Watch the video and discover the magic of Pingos.
Ice Wedges - Discover the how and why of ice wedges in the arctic.
Additional NPS Resources
Did You Know?
Bob Marshall named Frigid Crags and Boreal Mountain "The Gates of the Arctic." These mountains are on the North Fork of the Koyukuk River.