Thursday, August 6th 2020, 7:00 am - Grímsvötn’s 2011 eruption affected international air travel and sent a plume of ash and steam about 20 kilometres into the atmosphere.
Grímsvötn, Iceland’s most active volcano that is known for its 2011 eruption that temporarily shut down Icelandic airspace, could soon erupt.
The Icelandic Meteorological Office (IMO) says that an eruption is imminent based on several factors, including the ground movement near the volcano as magma underneath the Earth’s surface flows into the magma chamber.
Scientists in Alaska, Iceland and New Zealand are carefully monitoring Grímsvötn and they have noted that changing gas measurements are another indication that an eruption is likely, as reported by Columbia University’s GlacierHub.
“Currently we have a state of the volcano which is very similar to the pre-eruptive conditions before 2011 and 2004 [eruptions],” said Benedikt Ofeigsson, an IMO geoscientist during an interview with GlacierHub.
Gases such as sulfur dioxide and carbon dioxide are released from the volcano when magma travels towards the Earth’s surface, and the IMO recorded high concentrations of these gases in early June this year. Experts say that the eruption could occur within the next month or year.
Grímsvötn is a unique volcano because it is covered by the massive Vatnajökull, which is Europe's largest glacier. There is also a subglacial lake that lies underneath this ice. Heat from the volcano melts the ice, which forms this lake in the volcano’s crater.
Grimsvötn in Vatnajökull glacier in Iceland on July 29, 1972. Credit: Roger McLassus/ Wikimedia Commons. CC BY-SA 3.0
Significant amounts of heat released from the volcano can cause increased meltwater. As more ice melts, the pressure of the lake against the ice above it can become strong enough to cause a glacial outburst flood or jökulhlaup. Hundreds of square kilometres could be covered by a jökulhlaup and the sudden removal of water and pressure during this event can trigger the volcanic eruption.
Scientists are monitoring Grímsvötn's subglacial lake level for the first time because jökulhlaups have triggered many past eruptions, including the one in 2004.
Experts say that this volcano experiences a large eruption every 150 to 200 years and smaller ones every 5 to 10 years. The IMO states that the 2011 eruption was “a fairly large and powerful event” and that the upcoming eruption will be considerably smaller.
Grímsvötn’s eruption in 2011 affected international air travel and sent a plume of ash and steam about 20 kilometres (12 miles) into the atmosphere. Approximately 900 flights were cancelled between May 23 and 25 that year and several airports had to temporarily close.