What happens when a 'tornado' meets a volcano? Footage reveals a 3,300ft column of gas swirling above Bardarbunga



Stunning footage taken last week by an aircraft-fitted infrared camera

Tornado may have formed due to difference between hot and cold air

Hot air close to volcano rises punching through layer of cool air above

Circulating air currents then produce something similar to a dust devil

Icelandic Met Office says Bardabunga currently present no threat to flights



An incredible whirlwind of gas and fire, swirling 3,280ft (1km) into the air, has been captured above Iceland’s Bardarbunga volcano.

The stunning footage was taken last week by an aircraft-fitted infrared camera designed to monitor potentially dangerous ash clouds.

Scientists are still unsure what caused the tornado-like phenomenon, but have suggested it may be due to the difference between hot and colder air, causing something akin to a ‘dust devil.’

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An incredible tornado of gas and fire, swirling 3,280ft (1km) into the air, has been captured above Iceland's rumbling Bardarbunga volcano

'The generation mechanism is probably the same as that for dust devils, but in this case the tornado funnel is most likely filled with sulphur dioxide, gas and volcanic ash,’ said Nicarnica Aviation told Paul Marks at New Scientist.

Dust devils are small, rotating columns of air which can be seen because of the dust and debris they pick up from the ground.

They form because hot air close to the ground rises, punching through the layer of cooler denser air above.

The rising plumes of hot air and falling plumes of cool air begin circulating vertically in something known as ‘convection cells’.

This amazing aerial shots of the erupting Bardarbunga, Iceland's largest volcano. was taken by a helicopter hovering over the molten lava by photographer Iurie Belegurschi Steam and smoke rise over a fissure in a lava field north of the Vatnajokull glacier, which covers part of Bardarbunga volcano system. Yesterday morning, an earthquake struck the region around the volcano while fissures in the area continued to spew out lava Scientists are watching closely to see how molten rock at and below the surface will interact with glacial ice, surface melt, and groundwater

If a horizontal gust of wind blows, it turns the circulating air cells, so they begin spinning horizontally, forming vertical columns - and starting a dust devil.

Bardarbunga, which has erupted more lava than any other volcano on the planet in the last 10,000 years, has awakened since mid-August.

HOW DID 'FIRE TORNADO' FORM?

Scientists are still unsure what caused the tornado, but have suggested it may be due to the difference between hot and colder air, causing something akin to a ‘dust devil.’ Dust devils are small, rotating columns of air can be seen because of the dust and debris they pick up from the ground. Heated less-dense air close to the ground rises, punching through the layer of cooler denser air above. The rising plumes of hot air and falling plumes of cool air begin circulating vertically in something known as ‘convection cells’.

Yesterday morning, an earthquake struck the region around the volcano while fissures in the area continued to spew out lava.

The earthquake occurred at 0808 BST and reached a magnitude of 5.4, making it one of the bigger quakes in the area in central Iceland since significant tremors began on August 16.

'There was also another quake, magnitude 4.6 at 0430 (BST) in the night,' said Bergthora Thorbjarnardottir, geologist at the Icelandic Meteorological Office.

'Seismic activity underneath Bardarbunga volcano is still ongoing but remains steady,' she added.

Lava from the fissures around Bardarbunga has so far reached the surface only on land that is not covered by ice.

But scientists warn an eruption under an ice cap may be explosive and result in an ash cloud that could under certain circumstances disrupt aviation.

In 2010, a cloud of abrasive ash from the Eyjafjallajokull volcano, in a different region of Iceland, closed much of Europe's air space for six days after an eruption under the ice cap.

The ash warning level for aviation related to the current fissure eruptions remained at orange, the second-highest level on a five-colour scale, after several brief hikes to the top red in recent weeks.

The Icelandic Met Office says the lava eruptions and fire fountains from Bardabunga currently present no threat to flights.

Hot air rising above Bardarbunga, located under Vatnajökull, Iceland's most extensive glacier, is thought to have created the tornado of fire

Images of the gaping fissure, volatile lava fountains and a billowing cloud of steam and gas reveal the raw beauty and brute force of volcanic activity