Geophysists at the Met Office warn that next Vatnajökull glacier burst in river Skaftá, South Iceland, may turn into a natural hazard because of unusual conditions and that people in the area should beware.
Two sub-glacial lakes, Skaftárkatlar, in the western part of Vatnajökull, regularly fill up with melt water, due to geothermal heat, and cause floods that ordinarily rush down Skaftá.
Now, it’s been unusually long, or three years, since one of the lakes last flooded. Aerial footage shot a few days ago shows that there’s an extensive amount of water in that lake.
Glacier bursts caused by that lake, which is further to the east, are usually bigger than from the other one and the flow of the river can go up to 1.500 cubic metres per second, or five times the river’s average flow.
Furthermore, due to changes in the glacier itself the glacier burst might diverge and flood river Hverfisfljót as well but bridges there are not built to endure such an extensive flow.
“If more than one third of the flood rushes down Hverfisfljót, it might cause some danger there,” geophysist Bergur Einarsson told RÚV.
He added that the danger was not just due to water, which might damage roads and bridges. “Hydrogen sulphide, which has accumulated for many months by the edge of the glacier, will be released when the water floods from underneath the ice, which causes danger of eye or lung damage.”
The Met Office monitors the situation in the area carefully to be able to give some notice of when the glacier burst occurs.