Just before dawn on January 14, a kilometer-long volcanic fissure opened in the ground just north of the Icelandic town of Grindavík. Instead of roaring from a conical mountain, effusive fountains of crimson lava bled upward from this schism. Soon after, a smaller second fissure opened across the frost-flecked earth. Although intense, the eruption was mercifully brief—but it still destroyed three houses in the northeastern section of the town, which had been preemptively evacuated. Two days later, people displaced from Grindavík gathered at a sports hall in the Icelandic capital of Reykjavík to hear from politicians, scientists, and emergency managers and to discuss their town’s future. During the forum, Grindavík resident Bryndís Gunnlaugsdóttir said that the day that the eruption ended was the worst of her life because she discovered that her house had survived the invasion.
That may seem like a bizarre response to a volcanic eruption. But this is the new reality for Grindavík’s 3,600 residents. The January eruption was the second in as many months, and scientists are confident that the town will be imperiled by many more short but intense outbursts of lava emerging from any number of fissures for years to come—making Grindavík essentially uninhabitable.
Only homes that were directly affected by molten rock were eligible for monetary compensation, according to residents who attended the January gathering. If my house had burned down, I would have gained financial independence. I would be able to start a new home and this noose around my neck would be gone,” Gunnlaugsdóttir said at the forum.
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The town’s limbolike state may not remain a novelty for long. Grindavík sits on Iceland’s southwesterly Reykjanes Peninsula, which is a broken jigsaw of fissure-riddled volcanic systems. Until recently they had been quiet for 800 years. Yet before that time, the peninsula had been rocked by sporadic and intense eruptions over several centuries. Volcanologists now suspect that this strip of land—just west of Reykjavík—has entered a new volcanic era, wherein bodies of magma will repeatedly force their way through the surface at multiple locations.
There is a reasonable chance that the peninsula is “going into tens of years or hundreds of years of volcanic eruptions,” says Elísabet Pálmadóttir, a natural hazards expert at the Icelandic Meteorological Office. How, then, is the country going to defend itself? How is it going to try and coexist with the temperamental beast that stirs below?
Seething from the Ground
Fissure eruptions happen in certain volcanic regions worldwide, including on the slopes of Hawaiian volcanoes and across eastern Africa. But there may be nowhere on Earth quite like Reykjanes, making it as scientifically beguiling as it is hazardous. The Reykjanes Peninsula is dominated by fissure-style eruptions that vary in intensity, volume and duration. In 2020, after an 800-year interregnum, parts of the land started shaking, quaking and inflating, signifying the incursion of magma from deep below. In March 2021 magma found an escape route in an uninhabited valley adjacent to a small mountain named Fagradalsfjall, about 10 kilometers northeast of Grindavík. Two additional eruptions happened in the valley in the summers of 2022 and 2023; both were safely viewed from the surrounding hills by Icelanders and tourists alike.
Everything changed in November 2023. In the peninsula’s Svartsengi region—home to the popular Blue Lagoon spa, a critical geothermal power plant and Grindavík—seismic activity suddenly proliferated. The ground inflated rapidly—five centimeters at Mount Þorbjörnover a single week at one stage. The Icelandic Meteorological Office recognized that this geological activity could only mean one thing: A voluminous magma reservoir had emplaced itself into the shallow crust, and it had sprouted a vertical splinter of molten matter that quickly grew until it was just few hundred meters below the town.
Grindavík was swiftly evacuated. An eruption that lasted hours began on December 18. Fissures opened just north of the town, but the molten rock flowed away from it. A January 14 eruption was even more cursory, but it managed to bulldoze the town before fizzling out the very next day. Sadly, Grindavík’s woes have likely only just begun. Shortly after the eruption’s conclusion, scientists, watching the magma reservoir continue to inflate, suspected that another eruption is imminent. “It seems to be loading up for the next eruption,” Pálmadóttir says. Sure enough, on February 8 molten rock gushed from a three-kilometer crack close to the December eruption site. Although it flowed away from Grindavík, it intercepted one of the Svartsengi power plant’s pipes, cutting off hot water to at least 20,000 people.
The lava is not even the sole concern: earthquakes related to the magma’s movements have already fractured houses, water pipes and roads in large sections of town. “The whole crust is readjusting,” says Rhian Meara, a senior lecturer in geography at Swansea University in Wales, who focuses on social history related to volcanology. “The literal structure of the earth has changed beneath the town.” The lava may not have claimed any lives, but a construction worker fell into a crevasse in January, and he’s presumed dead.
Noxious volcanic gases may also be a problem—in particular, sulfur dioxide, which effuses from shallow magma. It can be an irritant at best and lethal at worst, especially if it pools in enclosed environments, such as basements, and displaces the oxygen there. Erupted metal pollutants can also leech into the environment, and fine particles in plumes can “penetrate deep into our airways,” says Evgenia Ilyinskaya, a volcanologist at the University of Leeds in England.
The situation in Grindavík is grim—which is why displaced residents (who are mostly staying with friends or relatives in other towns) are only allowed back, often under escort, for a few hours every now and then to check on their homes. Yet despite it all, residents and scientists are fighting back against the primordial force of nature.
Fighting Fissures
The Icelandic Meteorological Office (IMO), along with the University of Iceland and several international collaborators, has at least one meeting per day with the government’s Department of Civil Protection and Emergency Management (Civil Protection), which is coordinating the emergency management response. And because the peninsula is covered in geophysical instrumentation, scientists can follow the movement of the magma with remarkable precision in almost real time.
Molten lava is seen overflowing the road leading to the famous tourist destination "Blue Lagoon" near Grindavik, western Iceland on February 8, 2023. A volcanic eruption started on the Reykjanes peninsula in southwestern Iceland on Thursday, the third to hit the area since December, authorities said. Credit: Kristinn Magnusson/AFP via Getty Images
One great challenge with fissures is their unpredictability. Although scientists can approximate a region in which an eruption may be looming, “you don’t know where it’s actually going to surface” until the eruption starts, says Wendy Stovall, a volcanologist at the U.S. Geological Survey, who was on scene during the highly destructive, fissure-driven eruption of Hawaii’s Kīlauea volcano in 2018. That eruption had a relatively clear beginning and end, but the Reykjanes Peninsula is facing years, decades or even centuries of stop-start activity. “I think it is a rare situation,” says Sam Mitchell, a volcanologist at the University of Bristol in England. “This has shown a lot of people how unsteadiness and episodic activity can wreak havoc, societally and emotionally, in a way that we’ve not really seen before in historic times.”
Residents, of course, want to know if there is any way to repel the flow of lava. Back in 1973 a new volcano on the island of Heimaey began hastily building itself behind a nearby town. The paroxysmal cone, named Eldfell, plowed lava toward the town for 157 days. To slow its infernal advance, engineers pumped seawater from the harbor toward the red-hot lava’s leading edge. Although the molten rock still consumed land and property, the water reduced the lava’s pace, but serendipity was on the people’s side. “I suspect if it had kept erupting, it could have taken out the harbor,” says Amy Donovan, a volcanologist and natural hazards researcher at the University of Cambridge.
Not all of the infrastructure on the Reykjanes Peninsula is on the coast, however, and the scattershot appearance of multiple fissures would threaten any ad hoc water-pumping pipes and hoses. That leaves just one option. “All you can do, really, is build walls around the infrastructure,” Donovan says.
Lava Wall
The lives of Hjálmur Sigurðsson, a managing director of construction at the Icelandic contractor ÍSTAK, and Daði Freyr Þorgeirsson, a construction worker at the company, got considerably weirder on November 10, 2023, when the earthquakes indicated that magma was ascending toward Grindavík. The call went out: get here immediately. Sigurðsson and Þorgeirsson’s destination was fields of basalt (volcanic rock) close to the town and the Svartsengi power plant. The plan was to use that volcanic rock to build a wall between the likeliest site of the seemingly imminent eruption and the town and power plant.
Using excavators, they would scour up rock from the surrounding area and a nearby mine and truck it to the potential fissure locations. They would then dump the rock and subsequently mold it with diggers and bulldozers into barriers—berms several meters high and kilometers long. It seemed reasonable that the walls, made of the same stuff as any encroaching lava, could, for a time, deflect that lava away from the threatened sites. Scientists at IMO and the University of Iceland had been running computer simulations that, using the local topography, predicted the preferential flow directions of lava from various potential fissure sites—information that the construction crews could use to best place their walls.
The ensuing operation was complex and sometimes hectic. Construction workers saw this as a unique challenge, something almost perversely exciting. But everyone knew what was at stake—the existence of a town—and plenty had friends and family residing there. “My daughter lived in Grindavík at the time,” Sigurðsson says.
The crew was in constant radio contact with Civil Protection. At one point, the workers had to quickly stop work and flee: scientists could not guarantee that they could warn the crew about lava erupting nearby because a storm’s heavy winds and rain were disrupting their seismometers. “It was kind of scary,” Þorgeirsson says. “We were all working in the most dangerous zone.”
When the December 2023 eruption began, the walls were not yet complete. They were hundreds of meters, sometimes several kilometers, long but still needed to be connected. Thankfully, lava flowed away from them. But they proved invaluable on January 14, when the first of the two fissures opened around Grindavík. It had emerged to the north of the town’s defensive wall, but its flaming southern tip had dissected the barrier.
It was early in the morning, and the call went out to all wall builders who weren’t already on-site. As he approached Þorgeirsson thought, “This is insane! What are we doing?” When he arrived, he joined several dozen workers as they scrambled to extend the wall and ensure most of the lava was diverted away from Grindavík. Despite having to race against molten rock, which frequently surrounded them, the sight of the conflagration engendered a paradoxical sense of calm. “Now they could actually see the enemy,” Sigurðsson says. The danger was knowable, something that could be combatted.
In just a few hours, while jumping between multiple vehicles, making sure they were not engulfed by lava or toxic volcanic gases, the workers successfully lengthened the wall, and most of the molten rock was pushed away from the town. But their efforts were somewhat thwarted by the emergence of a second, smaller fissure that appeared just four hours after the first one. The new scar was inside the defensive walls—and right on the town’s perimeter. “How are we supposed to fight that?” Þorgeirsson asks. “Nature was just giving us the finger.”
And therein lies the terrible reality of fissure eruptions. Walls buy invaluable time—hopefully enough to prevent a short-lived eruption from causing significant damage. “But lava’s always going to win if there’s still lava to be erupted,” Stovall says.
Grindavík’s Ghosts
Grindavík is going to be a ghost town for the foreseeable future. The government is exploring various options, including allowing residents to shift capital from their homes to purchase new property elsewhere, constructing new housing and giving residents first dibs on it and temporarily freezing mortgage payments. The state may end up buying the homes from residents and then offering them back once the eruptive threat has definitively ended.
The closest analogue to the current crisis may be another common Icelandic hazard: avalanches. In 1995 two villages were struck by separate avalanches in the country’s Westfjords region, killing several dozen people and flattening a multitude of buildings. According to Ilyinskaya, these tragedies kick-started an effort to better understand the science behind these threats, and avalanche dams were erected to shield the villages as best as possible. Yet faced with such a lethal danger well into the future, the villages were partly uprooted and moved inland, away from the highest-risk area. Increasingly, that is how Icelanders are viewing Grindavík. “I know people from Grindavík, and they are not optimistic about ever going back because the town is just ruined,” Þorgeirsson says.
“Hopefully we can build another Grindavík somewhere else,” Pálmadóttir says. She thinks about this for a moment before shaking her head. “This is crazy,” Pálmadóttir says. It isn’t yet clear what locations may be suitable, and one could argue that even if the town were to move, it wouldn’t be Grindavík anymore: the identity of this maritime town may vanish if it’s shifted away from the shore.
It is plausible that the residents of Grindavík could be scattered across the country. If so, their jobs, their schools, even their communities would disappear. Their support networks would be dismantled. “That’s sometimes more traumatic than losing your actual house,” Meara says.
Even if relocating everyone in Grindavík proves to be the best solution, that cannot work for the entirety of Reykjanes and its surroundings. Most of Iceland’s population lives on or extremely near the peninsula. “We’re not going to move everyone,” Pálmadóttir says. She points to an area on a map where a concerning cluster of earthquakes had shaken another volcanic system in late January: Brennisteinsfjöll, a collection of fissures just a few miles southeast of the capital city.
“We expected other volcanic systems in the peninsula to wake up,” Pálmadóttir says. But she notes that some scientists consider the earthquakes to be routine, unrelated to magma. Still, should an eruption eventually begin there, “the flow direction is Reykjavík,” Pálmadóttir says.
If that were to happen, residents would know in advance when rivers of lava were heading their way thanks to Iceland’s world-class monitoring effort. It helps that every Icelander is steeped in geological knowledge, a priority of the country’s education system. Almost everyone will likely heed scientists’ warnings.
Regardless of what happens next, the recent volcanic awakening has irrevocably altered the Reykjanes Peninsula—and the entire country. Volcanoes have “mostly been a positive thing for us,” Pálmadóttir says. “It’s not something that’s really threatened us. It’s given us so much,” including wondrous natural environments, endless geothermal power and a lava-centric culture. But now the picture is murkier. “Maybe the mentality has changed in the last few months,” she says. “We just have to go with the flow.”