How large can pingos grow in Arctic regions?

Pingos are dome-shaped, ice-cored hills found in permafrost regions. While estimates of their maximum size vary across scientific sources, they can reach heights of up to 90 metres (approximately 300 feet) and span more than 800 metres (0.5 mile) in diameter. Other observations indicate that these landforms generally range from 3 to more than 60 metres in height and 15 to 450 metres in diameter.12

These features are categorized into two types based on their formation:
* Closed-system pingos: These form in flat areas, such as river deltas or near shallow lakes, where advancing permafrost creates pressure that pushes saturated soil upward. They are typically larger than open-system pingos.21
* Open-system pingos: These generally form on slopes in regions with thin or discontinuous permafrost, where artesian pressure forces groundwater toward the surface to freeze into a lens shape.21

Because pingos require specific environmental conditions to develop, they serve as valuable indicators of climate change.1