Volcanic hazards

Vestmannaeyjar, 1973. Photo: Oddur Sigurðsson.

There are a multitude of volcanic hazards, both due to volcanic activity and inherent to the environment around volcanoes. Different hazards are associated with the different volcanoes of Iceland, and can include jökulhlaup (glacial outburst floods), pyroclastic flows, volcanic emmission and ash dispersal, volcanic gases, earthquakes, lava flows, lightning, and landslides. Each of these hazards is discussed in more detail in the sub-pages on the left. Knowing the history of a volcanic system and understanding the behavior exhibited in the past by a given volcano is an important part of forecasting what a volcano may do in the future.

Volcanoes normally show some signs before erupting. An example of a precursor can be an increase in seismicity around the volcano, changes in the deformation observed on the surface of the earth, and changes in the geothermal systems and gas emissions related to the volcano. Each of these components of the volcanic systems are monitored to be able to detect changes. These precursors are usually related to the accumulation and movement of magma within a volcanic system. The precursory activity can be ongoing for a few minutes to years to decades before a volcano finally erupts, however, some volcanoes erupt without noticeable precursors at all, and some clearly observed events culminate in a magmatic intrusion that never reaches the surface of the earth.

The volcanic systems in Iceland are diverse and can exhibit a range of behaviors, so each volcanic system must be considered uniquely with regards to monitoring and research.

During a volcanic event, the Icelandic Meteorological Office (IMO) provides real-time monitoring data, summaries of activity, updates on developments, and other relevant information on this web-page. IMO works closely with the Department of Civil Protection and Emergency Management, who also display on their web-page information on hazards related to volcanic eruptions as well as details regarding preparedness and mitigation against imminent danger.

More information regarding natural hazards can be found e.g. in Icelandic in Náttúruvá á Íslandi. Eldgos og jarðskjálftar (Júlíus Sólnes, ed., 2013) and on the web page from United States Geological Survey

Surtsey, January, 1973. Photo: Oddur Sigurðsson.