The Awakening of Iceland’s Dormant Volcanoes: Unraveling Hofsjökull, Bárðarbunga, and Ljóssufjöll
In recent months, Iceland’s geologically active landscape has seen significant stirrings from volcanic systems long considered dormant. These events center around the Hofsjökull volcano, the Bárðarbunga region under Vatnajökull glacier, and the Ljóssufjöll volcanic system in West Iceland. Together, they paint a picture of increasing volcanic unrest across the island.
Hofsjökull: Iceland’s Sleeping Giant Stirs
Hofsjökull, often overlooked in favor of Iceland’s more active volcanoes, is experiencing unprecedented seismic activity. This glacier-capped volcano, which some debate as Iceland’s largest, is located in the island’s interior, surrounded by its own unique weather systems. Though quiet since the country’s settlement, its recent behavior suggests it may be awakening.
Historical Context
Hofsjökull was first identified as a volcano in the 1970s when scientists discovered a massive caldera beneath its glacier. Its seismic history remained uneventful until 2013, when a sudden flood attributed to geothermal activity beneath the glacier hinted at potential unrest. Since then, seismic activity has increased steadily, with a notable surge in December 2023 marking the highest levels ever recorded.
Current Observations
The volcano shares a fissure swarm with Kerlingafjöll, another central volcano nearby. Together, these two volcanoes sit on a rift fragment between Iceland’s main tectonic plate boundaries and the West Volcanic Zone. This geological setting complicates predictions, as limited historical records and sparse studies make Hofsjökull one of Iceland’s least understood volcanoes.
Inaccessible terrain further hinders research. The glacier spans 37 square kilometers and is reachable only by the Kjölur mountain road. Despite these challenges, Icelandic geologists are beginning to prioritize Hofsjökull, suspecting it could play a major role in future volcanic activity.
What Lies Ahead?
Although an eruption might still be decades away, the ongoing seismic unrest suggests magma movement beneath the surface. Scientists speculate that Hofsjökull’s dormancy may soon end, offering a rare chance to document activity in a historically quiet system.
Bárðarbunga and Vatnajökull: Iceland’s Volcanic Heartbeat
To the east, the Vatnajökull glacier—home to seven central volcanoes—is also showing signs of unrest. Bárðarbunga, one of Iceland’s most active and significant volcanic systems, has been experiencing seismic tremors alongside activity in the neighboring Hamarinn volcano.
Bárðarbunga’s Influence
Bárðarbunga, a 65 cubic-kilometer ice-filled caldera, has a history of triggering eruptions in nearby systems, such as Grímsvötn, which is now considered “ready to erupt.” The recent surge in seismic activity around Hamarinn, located 20 kilometers away, indicates that the two volcanoes may be interacting through a dense network of fractures beneath the surface.
Subglacial Eruption Potential
An eruption beneath Vatnajökull Glacier would likely produce spectacular imagery, as subglacial eruptions involve dramatic interactions between magma and ice. However, such events pose significant risks, including floods from glacial meltwater and ash clouds disrupting air travel. Bárðarbunga’s activity is being closely monitored, as it could herald a new cycle of eruptions in the region.
Ljóssufjöll: A Forgotten System Awakens in the West
In West Iceland, the Ljóssufjöll volcanic system has also started to rumble. This system, part of the West Iceland Volcanic Belt, has shown increased seismic activity over the past two years. Recent deep earthquakes beneath the region suggest magma is moving through the crust, similar to early patterns observed in the Reykjanes Peninsula before its eruptions in recent years.
Scientific Challenges
Despite its growing activity, Ljóssufjöll remains under-researched. New seismometers were installed only recently, limiting the availability of high-quality data. Nevertheless, scientists note that the patterns emerging in Ljóssufjöll resemble those seen in other volcanic systems prior to eruptions.
What’s Next for Ljóssufjöll?
While the activity could fade without an eruption, current trends suggest that magma is attempting to reach the surface. If this continues, Ljóssufjöll could become Iceland’s next active volcanic system, further intensifying the island’s already dynamic landscape.
A Wider Picture: Iceland’s Volcanic Future
Iceland’s volcanic systems are interconnected, influenced by the mantle plume beneath the island and the tectonic boundaries between the North American and Eurasian plates. Recent years have seen an overall increase in seismic activity across the country, leading some scientists to speculate that the mantle plume may be entering a more active phase.
While not all researchers agree on this theory, the evidence of increased unrest in Hofsjökull, Bárðarbunga, and Ljóssufjöll supports the notion that Iceland’s volcanic landscape is evolving. With each system responding to deep geological processes, the country may be entering a period of heightened volcanic activity.
Looking Ahead: Challenges and Opportunities
From Hofsjökull’s enigmatic past to Bárðarbunga’s volatile interactions, Iceland’s volcanoes are both a scientific challenge and an opportunity for discovery. Subglacial eruptions, tectonic shifts, and deep magma movements are creating a dynamic environment that demands close monitoring and further study.
As researchers work to unravel these mysteries, Iceland’s volcanoes remind us of the power and unpredictability of the Earth beneath our feet. For now, all eyes remain on these awakening giants, knowing that their next move could reshape the island’s landscape—and its history—once again.
