16:53 19 August 2014
Airlines have been warned about the possibility of flight disruptions caused by activity at Iceland’s largest volcano system. Although there are no signs of eruption, intense seismic tremors have been recorded at the Bardarbunga volcano for the past three days.
The Met Office has raised the risk level to orange – the fourth level on a five-level scale. It said: "As evidence of magma movement shallower than 10km (6.2 miles) implies increased potential of a volcanic eruption, the Bardarbunga aviation colour code has been changed to orange.
"Presently there are no signs of eruption, but it cannot be excluded that the current activity will result in an explosive sub-glacial eruption, leading to an outburst flood and ash emission.
"The situation is monitored closely."
In 2010, Iceland’s Eyjafjallajokull volcano produced a heavy ash cloud that paralysed Europe’s airspace for six days and disrupted more than 10 million.
Met Office seismologist Martin Hensch said that the risk of a disruptive ash cloud similar to the one in 2010 would depend on several factors including how high any ash coming from the volcano would be thrown.