PDF · Útgáfa NR-1800-958 — janúar 2025

Future proglacial lake evoluti­on and outburst flood hazard in Iceland – Final report

This project investigates future proglacial lake development and outburst flood hazard in south Iceland. Icelandic glaciers have lost 20 percent of their ice volume since 1890 and are predicted to lose at least 20 percent more by 2100. Much of this meltwater accumulates in proglacial lakes in front of glaciers, which can drain suddenly in jökulhlaups if a rock avalanche or landslide enters the lake and generates a tsunami-like wave that overtops the lake dam. These mass movement events become a greater risk in a warming climate as retreating glaciers remove support from valley walls, destabilizing slopes. Though this process triggers glacial lake outburst floods (GLOFs) worldwide, only one such event has occurred in Iceland—a 1967 jökulhlaup at Steinsholtsjökull. However, it will likely become a greater likelihood in future under projected climate warming. This project investigates: 1) How will Icelandic proglacial lakes evolve in a warming climate? 2) How will lake development affect outburst flood risk? 3) How will this hazard impact downstream infrastructure and communities?