It has slumbered for 290 years – but now more and more signs indicate that one of Iceland’s largest volcanoes is waking up and when it does, it could become very dangerous.

Öræfajökull is an ice-covered volcano in south-east Iceland. It is the largest active volcano on Iceland. The highest peak in Iceland at 2,110 meters (6,920 ft). Photo credit to Gummao

Under the thick ice cover, Öraefajokull in south-east Iceland has slumbered and remained calm since 1727 when the latest eruption took place. Before that, an eruption took place in 1362 according to historical records and in recent months, something has begun to happen below the glacier, again.

Researchers have detected clear warning signs of increasing activity within the volcano. More and more intensive seismic activity has been detected and with increasing flow of meltwater from the glacier. There is also a stronger smell of sulfur in the air around the volcano.

In addition to these signs, aerial photographs now show that an ice-bowl has begun to form on top of the glacier, just above the volcano. All in all, these are clear warning signs of an approaching volcanic eruption.

This particular volcano is especially dangerous since people live very close to it. With several villages located right next door. The Iceland meteorological institute has now raised the level of contingency to code yellow. This is a three on a five-grade scale, signaling approaching eruption and orange and red both signaling ongoing eruptions but at different levels of impact.

GREY: Volcano appears quiet but is not monitored adequately. An absence of unrest unconfirmed.
GREEN: Volcanic activity considered to have ceased, and volcano reverted to its normal, non-eruptive state.
YELLOW: Volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.
ORANGE: Volcanic eruption is underway with no or minor ash emission.
RED: Eruption is underway with significant emission of ash into the atmosphere.

Öraefajokull is part of Iceland’s largest glacier Vattnajökull, and besides spraying lava, ashes and gas, an outbreak can also cause violent floods of meltwater with floods that risk destroying everything in its vicinity.

This map is issued by the Icelandic Meteorological Office and it shows the current status of Icelandic volcanic systems. It is refreshed at 09:00 UTC daily and will timely reflect any signs of unrest.

A couple of thousand people live in the immediate vicinity of the volcano and when an eruption is indeed a fact, they will all need to be evacuated from the area.

Complicating the issue further is that in recent months, two more sleeping giants on Iceland’s more than 40 active volcanoes have shown signs of imminent eruptions. One is Bardarbunga, the largest volcano in the country, with an eruption in 2014 most recently. The other is Hekla, 150 kilometers southeast of the capital Reykjavik.

Photograph of the eruption from the summit of Eyjafjallajökull in 2010, from the north looking to the south across the Gígjökull outlet glacier, its “missing” proglacial (ice-margin) lake caused by the jökulhlaup that filled in the lake. Credit: Oddur Sigurðsson, Iceland Meteorological Office.

Besides threatening the people living in their vicinity of the vulcanos, the giant ash cloud that resulted from the eruption of the volcano Eyjafjallajokull in 2010 caused major air traffic disruptions in large parts of Europe and the U.S. for several days.

Reference:

Iceland meteorological institute A new ice-cauldron in Öræfajökull volcano