A strong earthquake swarm has started under the volcano this morning at around 6 a.m. local time. More than 100 quakes with magnitudes up to 5.0 have been recorded since. The strongest quake was a 5.0 shock at 08.05 am local time.
The quakes are clustered under the northern part of the large, completely ice-covered Bárðarbunga caldera, and located at depths spanning between 10 km and the surface. This is the strongest seismic activity of the volcano since the preceding seismic activity prior to its massive eruption in 2014-15. The activity closely resembles the pattern of a new magma intrusion, which is likely the cause.
This could (but by no means must) result in a new eruption, even in a very short term. If the eruption starts under the ice shield (where the current intrusion is taking place), it would result in potentially dangerous glacial melt-water floods (known as „jökulhlaups“). It also could lead to significant ash emissions once the erupted lava has melted a hole through the thick ice shield, and allows explosive interaction between magma and water to eject ash into the atmosphere – this in turn would depend on the duration and volume of such eruption.
While it is far from certain what might or might not follow, the aviation alert level of the volcano was raised to yellow and a „Level of Uncertainty“ was declared for Bárðarbunga by the Civil Protection. As of the latest information available, activity has slowed during the past few hours.