Icelandic authorities have raised a seismically-active volcano to the second-highest alert level on its aviation warning scale.
Intense activity had been detected at the Bardarbunga volcano on 16 August and the Icelandic Meteorological Office says that this situation “persists”.
It says there are “very strong indications of ongoing magma movement”. The Office adds that, at 02:37 on 18 August, it recorded the strongest earthquake measured in the region since 1996.
“The situation is monitored closely,” it states.
Magma movement shallower than 10km, the Office says, means increased potential for a more significant event. It adds that an “explosive sub-glacial eruption” with ash emission “cannot be excluded” as a consequence of the activity.
The Office has an aviation warning scale with five colour codes. It had already lifted Bardarbunga above its normal classification, but it has raised its status again, warning that the volcano is “exhibiting heightened or escalating unrest”.
Icelandic volcanic activity caused severe disruption across Europe in 2010 with the eruption of Eyjafjallajokull. The event led to an overhaul in the regulatory approach to dealing with such events, as well as the development of new technology to detect ash in the atmosphere.