A cluster of earthquakes at and around the Bardarbunga volcano have been recorded from August 16, prompting Iceland to raise its volcano alert to code orange.
Code orange is the second-highest level of risk, indicating that the “volcano is exhibiting signs of elevated unrest above known background level,” according to the International Civil Aviation Organisation.
Seismic activity may cause the volcano to erupt, although so far there are no indications that magma has reached the surface.
The eruption of Iceland’s Eyjafjallajokull volcano in 2010 shut down much of Europe’s airspace for six days, affecting the flights of 10 million people.
Volcanic ash consists of rocks, ash, sand and other particulates that are harmful to the plane engine. Glass melts when passing the combustion chamber, which has a temperature as high as 1,500 degrees Celsius.
The molten glass particles then stick to the turbine blades and bring them to a standstill. This can cause the engines to stall.