A 1.8-kilometre (1.1-mile) fissure opened on Beerenberg’s northeastern flank early Friday, sending ash and steam 3.1 kilometres (1.9 miles) above sea level. The opening is the first confirmed surface eruption at the Arctic volcano since 1985, according to the North Rim Geoscience Service, which monitors the remote Norwegian island of Jan Mayen.
Anna-Lena Axelsson, the service’s former lead eruption modeller, resigned on Thursday and says officials kept a high-end risk forecast out of public briefings for nine days. She told The Plausible Post that a larger eruption could send ash 12–16 kilometres (7.5–10 miles) high and into heavily used air routes as soon as this weekend.
The service confirmed the fissure and said its instruments had recorded “rapid changes” beneath the mountain. But its director, Mavin Norazman, described the eruption as “small and contained” and said there was no evidence that a larger blast was imminent. Axelsson says that statement leaves out the most alarming model run.
The forecast kept from view
Axelsson says she resigned after a risk chart she prepared on 21 October was removed from a briefing pack. The chart combined the earthquake swarm, ground uplift and a sharp rise in sulphur dioxide readings, and showed a 12–16-kilometre plume as a credible worst case if a larger magma chamber opened. The figures are projections, not a prediction that such an eruption will occur.
“The public was given the quietest version while the instruments were telling us the system was changing fast,” Axelsson said. She said she had urged the service to raise its aviation warning before the fissure appeared. The service did not respond to her account of the chart’s removal, but said it was checking how risk scenarios had been communicated.
A small vent does not tell us how much magma is moving below it.
Anna-Lena Axelsson, former lead eruption modeller
The service’s public updates show 1,284 earthquakes in the 36 hours before the fissure opened, compared with fewer than 40 a day earlier in the month. Satellite measurements indicate 11 centimetres (4.3 inches) of uplift over 19 days. A separate instrument measured a sudden increase in sulphur dioxide, a volcanic gas that can help scientists track magma movement.
Flights and crews on alert
Norazman said the plume had not reached the height at which widespread flight restrictions would normally be considered. The North Atlantic Flight Coordination Office is preparing for a different possibility: its preliminary map places about 280 daily transatlantic crossings near the forecast ash corridor if winds carry a taller plume south-east. It has asked airlines to prepare alternate routes, but has not ordered cancellations.
Jan Mayen has no permanent civilian population, but its research station normally houses 18 staff. Four are staying to maintain instruments as a Norwegian coast-guard vessel brings the other 14 to safety; the service says the transfer is precautionary. Rogelio Mitchell, an aviation adviser to the coordination office, said a high plume could force diversions across several routes for days, depending on wind and ash concentration.
The dispute has already reached markets. Shares in three small Arctic minerals explorers fell between 6% and 11% in Oslo trading on Friday as investors weighed the risk to a proposed NOK 3.1 billion (about €270 million) copper and rare-earth survey programme elsewhere in the region. The companies have no operations on Jan Mayen, and there is no evidence the planned work affected the service’s warning decisions.
The service says it will publish an updated hazard map by 18:00 and review the timeline of its alerts. Axelsson says the fissure is only the visible part of the problem: “The next 24 to 48 hours will tell us whether this is a short-lived crack or the opening act of something much larger.”
