Volcanism of Iceland

The most fatal volcanic eruption of Iceland's history was the so-called Skaftáreldar (fires of Skaftá) in 1783–84. The eruption was in the crater row Lakagígar (craters of Laki) southwest of Vatnajökull glacier. The craters are a part of a larger volcanic system with the subglacial Grímsvötn as a central volcano. Roughly a quarter of the Icelandic nation died because of the eruption. Most died not because of the lava flow or other direct effects of the eruption, but from indirect effects, including changes in climate and illnesses in livestock in the following years caused by the ash and poisonous gases from the eruption. The 1783 eruption in Lakagígar is thought to have erupted the largest quantity of lava from a single eruption in historic times.

The eruption under Eyjafjallajökull ("glacier of Eyjafjöll") in April 2010 was notable for causing enormous disruption to air travel across western and northern Europe over a period of six days in April 2010. About 20 countries closed their airspace to commercial jet traffic and it affected approximately 10 million travellers.[5]

However this volcano is minor in Icelandic terms (VEI4)[6] In the past, eruptions of Eyjafjallajökull have been followed by eruption of the larger volcano Katla, but after the 2010 eruption no signs of an imminent eruption of Katla were seen. [7]

The eruption in May 2011 at Grímsvötn under the Vatnajökull glacier sent thousands of tonnes of ash into the sky in a few days, raising concerns of a repeat of the travel chaos seen across northern Europe.

The craters of Grábrók

Bárðarbunga is a stratovolcano and is roughly 2,000 meters (roughly 6,560 feet) above sea level in central Iceland (64.63°N / -17.53°W).[8] This makes it the second highest mountain in Iceland.

The eruption series, Iceland's largest eruptions in 230 years[9] that started on August 17, 2014 and lasted for 180 days,[10] under the Bárðarbunga system started with an extremely heavy earthquake swarm followed by clusters of volcanic activity that went on for an extended period. This resulted in multiple lava fountain eruptions in Holuhraun.[11] Lava flow was between 250 and 350 cubic meters per second and came from a dyke over 40 km long.[12][13] An ice-filled subsidence bowl over 100 square kilometers in area and up to 65 meters deep formed as well.[14] There was very limited ash output from this eruption unlike numerous glacial eruptions which are common in Iceland. The primary concern with this eruption was the large plumes of sulphur dioxide (SO2) in the atmosphere which adversely affected breathing conditions across Iceland, depending on wind direction. The volcanic cloud was also transported toward Western Europe in September 2014.[15]