Thermokarst activity ceases when a balance is restored between surface energy inputs and the depth of seasonal thawing. In areas of thin permafrost, this may involve the disappearance of permafrost. But where the permafrost is thick or cold, thermokarst activity often ceases and the ground surface stabilizes before all of the excess ice has ablated. For example, thermal erosion may cease where deposition of sediment buries exposed ground ice, where differential thaw along gully axes eliminates drainage gradients (Lawson 1982), or where water trapped in underground channels and pools freezes to form pool ice (Mackay 1988).

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