Fears entire Iceland town could be hit by lava after sulphur dioxide levels spark evacuation: 'Considerable uncertainty over the future' of Grindavik as nine-mile fissure splits town and 800 quakes are felt in sign that volcanic eruption is imminent

Fears for the future of an Icelandic fishing town are mounting as a nearby volcano threatens to erupt at any moment - with a nine-mile fissure splitting the town in half and authorities saying that increased sulphur dioxide levels have been detected.

Aerial footage shows apocalyptic scenes in the small town of Grindavik, with huge cracks appearing in roads and under buildings which were completely deserted when all 4,000 residents were told to evacuate.

Residents who were allowed to return to their homes with emergency services to collect essentials were ordered to evacuate this afternoon after the Icelandic Met Office said their meters had detected increased levels of SO2.

Sulphur dioxide is a toxic gas released by magma as it rises to the surface, and high exposure is deadly to humans. If detected at a non-erupting volcano, it could be a sign that it will erupt soon. 

The whole country 'is on edge' waiting for a possible eruption of the Fagradalsfjall volcano, with experts warning that thousands of earthquakes over recent days could signal that a blast is imminent.

More than 800 quakes have been recorded in the southwestern Reykjanes Peninsula since yesterday, and despite them being slightly weaker and fewer occurring than in previous days, the volcano is still expected to erupt.

'Less seismic activity typically precedes an eruption, because you have come so close to the surface that you cannot build up a lot of tension to trigger large earthquakes,' said Rikke Pedersen, who heads the Nordic Volcanological Centre based in Reykjavik.

'It should never be taken as a sign that an outbreak is not on the way,' she said.

The Icelandic Met Office informed police today that their new meters had detected increased levels of sulphur dioxide, prompting the police chief to evacuate Grindavík, Met Office official Benedikt Ofeigsson said.

He told Icelandic broadcaster RUV that there was no indications on other devices that an eruption was starting, but that they still did not want to rule it out, explaining that SO2 does not appear in this way unless magma is very high in the earth's crust.

He urged people to be 'super careful', and following the warnings Grindavik has been entirely evacuated, local media reports.

A state of emergency declared on Friday and around 4,000 people were ordered to leave the fishing community hours later.

Evacuated residents reported hearing 'unholy sounds' from beneath the ground as they fled and feeling 'seasick' from the constant tremors.

Residents were allowed to return in groups over recent days to collect belongings from their deserted homes, being told by officials as they entered: 'If you hear sirens, drop everything and get out!'

Huge sinkholes have opened up around the town, while aerial footage has captured the scale of huge tears in the earth caused by the seismic activity.

Dramatic footage captured by a Coast Guard plane shows a chasm running through the centre of the town, with smoke pouring out of the gaping splits as magma rises. 

Meanwhile, authorities are urgently preparing to build defence walls around a nearby geothermal power plant which they desperately hope will protect it from lava flows - amid concerns that a volcanic eruption could be imminent.

Iceland's Justice Minister Gudrun Hafsteinsdottir told RUV on Tuesday that a large dike has been designed to protect the Svartsengi geothermal power plant, located just over six kilometers from Grindavik.

Equipment and materials that could fill 20,000 trucks were being moved to the plant, she said, and construction is awaiting formal approval from the government.

The plant produces hot and cold water and electricity for the entire country and a spokesperson for its operator, HS Orka, said a disruption would not impact power supply to the capital Reykjavik.

Magma has been accumulating under the town and experts said yesterday that a 'corridor' around nine miles (14km) long has developed beneath it, with an eruption possible anywhere along the intrusion. 

Fears have been mounting that an eruption could see a repeat of the chaos caused by the 2010 Eyjafjallajokull eruption, however volcanologists have said that Fagradalsfjall would not produce a huge ash cloud as it did if it does blow.

Matthew James Roberts, director of the service and research division at Iceland's meteorological office said: 'We believe that this intrusion is literally hovering, sitting in equilibrium now just below the earth's surface.

'We have this tremendous uncertainty now. Will there be an eruption and if so, what sort of damage will occur?'

The head of the Department of Public Safety has said it is getting 'more and more difficult' to get into the area of Grinvadik as giant chasms continue to widen.

'That area continues to sink and new cracks are constantly forming on the surface. We define this area a bit like a sliding glacier that is heavily cracked and even covered with snow, so it is very dangerous to be inside that area.'

While people have been able to make quick trips to their homes in recent days to gather belongings and retrieve pets, anyone who has been unable to do so thus far will need extra safety precautions if returning today, he said.

Authorities have warned that anyone hoping to return will need to be accompanied by emergency personnel. 

Residents have shared videos making their way back into the deserted fishing town, with officials warning them to urgently retreat if they hear warning sirens.

One documented his return on TikTok, filming a long queue of cars making their way back into the town temporarily with officials stopping each to give safety advice.

An emergency worker stops the man to ask if he is a Grinvadik resident, before advising him: 'If you hear any sirens, airhorns or anything similar, then get out! Drop everything and get out!'

The Civil Protection Authority stressed in a statement that the area around Grinvadik is dangerous. 

'The Weather Bureau continues to measure ongoing and constant ground deformation in the vertical displacement which has formed near Grindavik,' it said.

'Intrusions can form without any notice, as well as volcanic activity. A volcanic eruption is likely in the area.'

It added that 'rapid land upheaval' is being measured around Svartsengi.

Local media reports that seismic activity overnight was similar to the day before, with 'about a hundred tremors per hour'. Most were small, but the largest measured 3.1 and 2.8 in size, according to Visir.is.

Hans Vera, a Belgian-born 56-year-old who has lived in Iceland since 1999, said there had been a constant shaking of his family's house.

'You would never be steady, it was always shaking, so there was no way to get sleep,' said Vera, who is now staying at his sister-in-law's home in a Reykjavik suburb.

'It's not only the people in Grindavik who are shocked about this situation it's the whole of Iceland.'

'We are really concerned about all the houses and the infrastructure in the area,' head of Iceland's Civil Protection and Emergency Management, Reynisson said earlier this week.

'The magma is now at a very shallow depth, so we're expecting an eruption within a couple of hours at the shortest, but at least within a couple of days.'

Icelanders are 'essentially just waiting', local journalist Holmfridur Gisladottir told Sky News on Monday.

A looming eruption has revived the trauma of the 2010 explosion at another of Iceland's volcanoes, Eyjafjallajokull, for many locals.

It produced a huge cloud of ash which prompted the biggest shutdown of global aviation since the Second World War, with 50,000 flights cancelled and eight million passengers affected.

Discussing the differences between a potential eruption of Fagradalsfjall and Eyjafjallajokull, Mr Roberts said an eruption could see lava spew over the town, but was less likely to cause the same ash blast. 

He told BBC R4's Today programme on Monday: 'First of all there isn't an ice cap on top and it's not a stratovolcano so wouldn't be an explosive blast of volcanic ash into the atmosphere.

'This would be a lava-producing volcanic eruption along a series of fissures and that would be the main hazard.'

He added that an eruption 'that persists for weeks' is possible, meaning roads and other infrastructure could be 'in harm's way'.

Located between the Eurasian and the North American tectonic plates, among the largest on the planet, Iceland is a seismic and volcanic hot spot as the two plates move in opposite directions.

In March 2021, lava fountains erupted spectacularly from a fissure in the ground measuring between 500-750 metres long in the region's Fagradalsfjall volcanic system. 

Volcanic activity in the area continued for six months that year, prompting thousands of Icelanders and tourists to visit the scene. 

In August 2022, a three-week eruption happened in the same area, followed by another in July of this year. 

Iceland volcano: Scientists reveal just how big an eruption could be - and whether it could produce another huge ash cloud like Eyjafjallajokull in 2010

By Jonathan Chadwick 

Iceland – one of the biggest volcanic hotspots in the world – has declared a state of emergency over the latest threat of eruption. 

Around 4,000 people have been forced from their homes in the town of Grindavik due to its proximity to the Fagradalsfjall volcano on the Reykjanes peninsula, while the popular Blue Lagoon tourist attraction has been closed. 

For many locals, the episode has revived the trauma of the disastrous explosion at another of Iceland's volcanoes, Eyjafjallajokull, back in 2010. 

While the eruption didn't kill anyone, it did produce a huge cloud of ash that prompted the biggest global aviation shutdown since World War II.

Now, scientists have revealed to MailOnline just how big an eruption could be and if it could rival Eyjafjallajokull, which saw 50,000 flights cancelled and 8million passengers affected. 

Dr Dave McGarvie, a volcanologist at the University of Lancaster, said the huge ash cloud like the one we saw 13 years ago is unlikely to happen again right now. 

'A potential future eruption arising from the current unrest will not lead to disruption like that of the Eyjafjallajökull 2010 eruption,' he said. 

'Eruptions on the Reykjanes Peninsula are dominated by basalt lava production with only minor ash production, whereas the Eyjafjallajökull 2010 eruption was dominated by ash production.

'So it is extremely unlikely that an eruption arising from the current unrest will cause disruption to transatlantic air travel.' 

Although Iceland's capital Reykjavik is well outside the danger zone, Iceland's airport of Keflavík lies around 10 miles (17 km) northwest of the area of unrest. 

At the moment, flights are departing and arriving at Keflavik – Iceland's primary international airport – as usual. 

However, as a precaution for domestic and international air travel, the volcanic aviation colour code for the Reykjanes Peninsula is now orange (heightened unrest). 

The orange alert represents the third-highest level, although it poses limited hazards to aviation. 

The next stage is red, reserved for an imminent or ongoing volcanic eruption that could seriously affect aviation, but this is unlikely. 

Iceland is a particular hotspot for seismic activity because it sits on a tectonic plate boundary called the Mid Atlantic Ridge.

The Mid Atlantic Ridge is a long chain of mountains that stretches down the Atlantic ocean, meaning most of these mountains are underground. It's gradually pushing North America and Eurasia away from each other.

There are only a few places on Earth where the Mid Atlantic Ridge is exposed on land, but Iceland – which is slap bang in the middle of the ridge – is one of them. 

But Iceland is also located over a mantle plume – a column of hot, molten rock that rises from the deep mantle to the surface, becoming lava when it erupts.

In the past week, Grindavik has become lined with massive cracks in the land that are billowing out steam – the result of magma moving underground that pushes up on the Earth's crust. 

Authorities are fearing eruptions of basalt lava – viscous molten rock – that comes to the surface in the region through the cracks right underneath buildings. 

Dr Carmen Solana, a volcanologist at the University of Portsmouth, said magma is very close to the surface' – around 1 to 2 km (0.6 to 1.2 miles) – and an eruption could occur 'at any time'.

'This series of volcanic unrest is creating large earthquakes and a lot of deformation as you can see from the images of cracking roads and the smoke coming to the surface,' she told MailOnline. 

Residents have been evacuated because of the concern that cracks could 'open literally underneath houses', she said, leading to 'complete destruction' of Grindavik which is a key part of the country's fishing industry. 

Dr Solana agreed that an imminent eruption would not cause similar travel disruption like that of the 2010 eruption. 

'Eyjafjallajokull in 2010 was actually a small eruption but it happened on a volcano underneath an ice cap,' she said. 

'The interaction of magma with ice, increased the explosivity, broke the magma into very small pieces of ash that went into the atmosphere.

'This is not the scenario that we're looking at here.'  

Despite the build-up of activity, Dr Solana added that an eruption might not actually happen. 

'At the moment we don't even know if there's going to be an eruption,' she told MailOnline. 

'How much magma is going to come, we don't really know.

'There might be an accumulation of magma beneath the surface but that doesn't mean that all of that is going to come to the surface.' 

Professor Marc K. Reichow, a geochemistat the, University of Leicester, said it's 'difficult to say' what the potential size or scale of an eruption will be.

'Depending whether this eruption will take place the proximity to local residences could be dangerous and cause damage to buildings,' he said. 

'The area has been evacuated and hazard to life is currently minimal.'

Almannavarnir, part of Iceland's Department of Civil Protection and Emergency Management, has a dedicated advice page that details Grindavík's evacuation plan.

Residents should close windows, unplug electrical appliances and secure the home before putting a sign outside to show the house is vacated. 

It says: 'Residents must evacuate their homes and leave town. This is not an emergency evacuation. It is our request to the residents of Grindavík to leave the town without any trouble. 

'There is no immediate danger imminent, the evacuation is primarily preventive with the safety of all Grindvíkin in the first place.'