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Bradgate Park, we're back investigating ~14,000 year old archaeology
Pingo is the Eskimo word for “hill”.
A pingo is a hill formed by the upheaval of ice underneath the soil in regions characterized by permafrost.
They are typically conical in shape and can grow up to 70 meters high and 1000 meters in diameter. Pingos are found in Arctic and subarctic regions where the ground is permanently frozen.
Pingos are important features of the Arctic landscape and provide valuable information about the history of permafrost and climate change. They are also home to a variety of unique plants and animals.
Image: Ibyuk pingo near Tuktoyaktuk, northern Canada.
Discontinuous permafrost is a region where permafrost is present in some areas, but not in others. The term "discontinuous" refers to the lateral continuity of permafrost. It is associated with the Subarctic zone, and most of it is much younger, having formed within the last several thousand years.
Talik: in permafrost regions, unfrozen ground is called talik. It occurs due to local anomalies in thermal, hydrological, hydrogeological, or hydrochemical conditions.
Active layer: The top of the permafrost thaws and freezes on an annual basis, and the maximum seasonal thaw depth is called the active layer.
There are two main types of pingos:
Open-system or hydraulic pingos: These form when groundwater flows into a closed depression in the permafrost. Hydrostatic pressure initializes the formation of the ice core as water is pushed up and subsequently freezes. It expands and pushes up the overlying soil, creating a hill.
Closed-system hydrostatic pingos: These form when a lake freezes over and the ice expands, pushing up the lakebed. As the lakebed freezes, it creates a core of ice that continues to grow, pushing up the surrounding soil.
The British pingos may relate to the last, Late Devensian ice age, 12,000 to 33,000 years ago.
This is an example of pingo remnants near Retford, England.
The Pingo Trail Walk in Norfolk takes you around 'ponds', in reality the water-filled depressions or kettle holes that were left behind when the ice lens under a pingo melted.
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