An intense seismic activity at Bárðarbunga (Vatnajokull area) has started on 16 of Agust. During the past 3 days, thousand of earthquakes in the area have been registred. The Icelandic Metereological Office (IMO) reports that very strong indications of ongoing magma movement, in connection with dyke intrusion, is corroborated by GPS measurements. There are currently two swarms: one to the E of Bárðarbunga caldera and one at the edge of Dyngjujökull just E of Kistufell. At 2.37 am on the 18th a strong earthquake (M4) was located in the Kistufell swarm.This is the strongest earthquake measured in the region since 1996. As evidence of magma movement shallower than 10 km implies increased potential of a volcanic eruption, the Bárðarbunga aviation color code has been changed to orange. Presently there are no signs of eruption, but it cannot be excluded that the current activity will result in an explosive subglacial eruption, leading to an outburst flood (jökulhlaup) and ash emission. The situation is monitored closely.
The "Aviation color code map" (issued by the Icelandic Meteorological Office, in accordance with recommended International Civil Aviation Organisation (ICAO) procedures) shows the current status of Icelandic volcanic systems: Bárðarbunga is now labeled orange, "Volcano shows heightened or escalating unrest with increased potential of eruption".
Four years after Eyjafjallajokull blew, disrupting European air travel and costing $ 1.7 billion (accordingly to Reuters), there are chances that Bárðarbunga may affect again European aviation. Scientists said Monday there are two scenarios: one is an explosion outside the Vatnajokull glacier, leading to minor ash emissions and troubles locally (in the meanwhile Icelandic autorities have closed the roads around the area, due to possible floodings as consequence of ice-melting due to underground magma movements).
The second possibility is an eruption occurring inside the glaciar. Seismologis5t Martin Hensch says the latter could lead to ash being sent high into the atmosphere.