Velocity measurements from a GPS-station run by IES of near the equilibrium line of Dyngjujökul show that a surge is likely stared. Dyngjujökull in northern Vatnajökull is a surge type glacier, typically surging with 20–30 year interval. It surged last time in 1998–2000, when 21 year had passed from last surge. Since 1992 velocity stakes have been deployed on the glacier in the spring and revisited and measured in the autumn. In the years preceding last surge the velocity near the equilibrium line gradually increased from 60 m/year to 80 m/year, until the summer 1998 when the velocity jumped to 140 m/year at a start of a surge (see figure below). In 1999 to 2004 crevasses formed by the surge made it impossible to deploy stakes in this area, but in 2005–2015 the movement of this area was close to 50 m/year but increased gradually to 80 m/year in 2015–2024. A GPS-station deployed last spring shows a jump in the velocity but since start of July the average velocity corresponds to 150 m/year, slightly above the velocity in the summer of 1998. A surge has therefore likely started. We advice people not to travel over Dyngjujökull. Crevasses have probably already started to form in areas on Dyngjujökull, which in the past 20 years has been uncrevassed and safe to travel across.
Finnur Pálsson and Eyjólfur Magnússon, 12. November 2025
