ABSTRACT
This chapter considers landscapes underlain by either continuous or patchy permafrost (permanently frozen ground) – periglacial landscapes. It begins with a look at processes operative in periglacial environments: frost action, solifluction (frost creep and gelifluction), nivation, as well as fluvial and aeolian action. It shows how these processes fashion ground-ice landforms (ice wedges and a range of frost mounds – pingos, palsa, peat plateaux, string bogs, frost blisters, icing mounds, and icing blisters), ground-ice degradation landforms (thermokarst and oriented lakes), landforms resulting from seasonal freezing and thawing (patterned ground and periglacial slopes), and cryoplanation terraces. The chapter then explains how human-induced climate change is leading to permafrost degradation and the formation of thermokarst. Finally, it outlines the current periglacial features that are vestiges of frigid conditions during the Quaternary ice ages.
