A minor glacial outburst flood in Skaftá
Warning - jökulhlaup in progress
Within recent days, the level of the Skaftá river at Sveinstindur has risen slowly. Additionally electrical conductivity readings from the same location have increased. These observations suggest that a glacial outburst flood (jökulhlaup) is in progress.
It is likely that the flood originates from the western Skaftá ice cauldron, which last drained in June 2015; however this is unconfirmed until visual observations are made. The discharge of Skaftá at Sveinstindur at noon was 112 cubic metres per second.
The flood is not expected to cause any downstream disruption, although the following points should be kept in mind:
- Hydrogen sulphide is released from the floodwater as it drains from the Vatnajökull ice-cap. The gas is particularly potent at the ice margin, where concentrations will reach poisonous levels. Travellers must stay away from the edges of Skaftárjökull, Tungnaárjökull and Síðujökull while the flood occurs.
- Crevasses will develop rapidly around the ice cauldron, so travellers on Vatnajökull should stay away from the region, including the lower part of Skaftárjökull and Tungnaárjökull, where floodwater could burst through the surface.
The situation is being monitored closely.
Natural hazard specialists
Bryndís Ýr Gísladóttir
Matthew J. Roberts