AP BIOLOGY

Detailed explanation-1: -The presence of permafrost retards the downward movement of water though the soil, and lowlands of the Arctic tundra become saturated and boggy during the summer thaw. During the winter, water in the soil can freeze into a lens of ice that causes the ground above it to form into a hilly structure called a pingo.

Detailed explanation-2: -If you dig down through the arctic tundra, you’ll soon strike a rock-like layer of frozen soil. Even on the warmest summer day, this permafrost layer lies anywhere from a few inches to a few feet below the tundra surface, never thawing. About 85% of Alaska’s land area is underlain by permafrost.

Detailed explanation-3: -Permafrost is any ground that remains completely frozen-32°F (0°C) or colder-for at least two years straight. These permanently frozen grounds are most common in regions with high mountains and in Earth’s higher latitudes-near the North and South Poles.

Detailed explanation-4: -The majority of soils in Arctic tundra regions are classified as a Cryosol. Cryosols are mineral soils that are formed in an environment underlain by permafrost, thus they are often referred to as permafrost soils. Permafrost is ground that remains at or below 0 degrees Celsius for two or more years.

Detailed explanation-5: -Continuous permafrost is defined in the name itself, which is a continuous sheet of frozen material. Continuous permafrost extends under all surfaces except large bodies of water in the area. It exists under almost the entire land surface in an area.