How does thawing ground ice create thermokarst landforms?

Thermokarst landforms are created when ground ice within permafrost melts, causing the overlying ground to settle unevenly. This process can be triggered by natural factors, such as a warming climate, or by human activities like deforestation, agriculture, or construction.12

As the ice thaws, the ground surface collapses, resulting in a characteristic hummocky topography that resembles the karst landscapes found in limestone regions. Specific features formed by this process include:12

• Depressions and Pits: Small pits, sinkholes, and steep-walled ravines.12
• Thaw Lakes: Depressions that fill with water, often referred to as thermokarst or cave-in lakes.2
• Mounds: Polygonal or circular hummocks that remain as the surrounding ice-rich network melts.2
• Subsurface Features: Tunnels and caverns that may exist undetected until the surface roof collapses.2

The scale and appearance of these landforms depend on the nature and extent of the ice present in the ground.1