Abstract: Glacier lake outburst floods (GLOFs) refer to sudden and in some cases cyclic release of meltwater from a glacier-dammed or moraine-dammed lake, which can result in a catastrophic flood. Thorarinsson (1939) introduced the term “jökulhlaup” for glacial floods due to the cataclysmic drainage of subglacial lakes in Iceland. It was originally referred to outburst floods triggered by volcanic activity and has been subsequently transferred to a variety of other types of glacial floods. It has become a widely used synonym for describing catastrophic glacial floods in general.