An Icelandic Glacier. Photo by Páll Stefánsson.
These are similar to palpitations that occurred in 1994 and 1999, which were cases of magma intrusion. In 1999, the palpitations impacted the volcano Katla even if they did not cause an eruption.
“Volcanic activity under Eyjafjallajökull Glacier is known to be able to trigger eruption in Katla due to the proximity of the two,” explains geophysicist Páll Einarsson.
He says that seismic activity can cause Katla to erupt. “That is what happened in 1821 when an eruption in Eyjafjallajökull Glacier lasted two years, eventually leading to an eruption in Katla in 1823.”
Einarsson adds that it could take months to determine what is going on under the Glacier. “The investigation took a long time in 1994 and 1999 but we are probably facing the beginning of a magma intrusion. We measure that by monitoring the uplift of the terrain.”