Vatnajökull glacier. Photo by Páll Stefánsson.
The flow of Skaftá river had reached 270 cubic meters per second last night, which was twice the amount of the night before. The flood began shortly after 2 pm yesterday under Vatnajökull glacier beneath Sveinstindur peak, south of Langisjór lake.
The flood originates from a caldera under the glacier, into which water melting because of geothermal heat gathers. This water then regularly erupts and causes Skaftá to flood. This last happened in October 2008.
There are two calderas and it is not known which of them is the cause of the flood. Skaftá floods usually cause little damage, except to vegetation. People are not in danger, the Kirkjubaejarklaustur police told ruv.is.