Volcanic eruption:
Additional insight

Volcanic eruptions have a movie star quality about them, not least because for most people across the globe, they are not a part of their daily reality. However, of the approximately 1,500 active land volcanoes around the world, at least 16 are considered risky enough to warrant special attention. 

Not all volcanoes are created equal

The ‘Decade Volcanoes’, so-called because researchers began looking into them during the UN’s International Decade for Natural Disaster Reduction, are deemed highly dangerous because they fulfil the following criteria: people nearby will be in the direct line of material from the eruption such as ash or lava; it’s showing signs of activity and is in a populated area^[10].

Volcanic eruption warning signs

While volcanic eruptions themselves are relatively rare events, “volcanic unrest” (such as seismic activity, ground deformation and uplift, volcanic gases, hydrothermal explosion, and landslides^[11])  is far more common and we should be alert to the warning signs that a major eruption is geologically imminent. In the 1930s there were observations of volcanic unrest on the island of Montserrat for several decades. It wasn’t until between 1995-1997 that the major eruption happened which destroyed nearly two-thirds of the island and highlighted a lack of financial preparedness.^[12]

The direct impacts of an eruption on the neighbouring land may be clear, and wider reaching effects may be less so, however recent eruptions have demonstrated just how widespread the literal and figurative fallout can be.

Beware the secondary impact

In 2010, when Iceland’s Eyjafjallajökull erupted, the people on the ground were safe however, the resulting ash from the eruption rose high into the stratosphere and covering most of the Arctic, northernmost North America and Europe, putting it directly in the path of one of the busiest aviation corridors on Earth. As aviation authorities deemed it too dangerous to fly through the cloud because of the risk to engines, much of European and northern airspace was shut down for six days. However, the financial impact was felt for much longer.

Volcanoes and the internet

The most significant eruption in terms of physical destruction and long-lasting impact was Indonesia’s Mount Tambora in 1815. The explosion could be heard in Australia and it caused famine, disease and temporary worldwide climate change. However, one of the most recent events off the coast of Tonga, the 2022 Hunga Tonga eruption, gives us an insight into how eruptions could easily cause global disruption.

While the resulting tsunami caused physical devastation in the local area, it was hard to get information in and out of the area due to extensive damage to undersea cables. As our modern world relies so heavily on digital technologies, widespread damage to these critical conduits could effectively shut down parts of the internet.

^{[10] https://www.sciencedaily.com/terms/decade_volcanoes.htm}   

^{[11] Charlton, D., Kilburn, C. & Edwards, S. Volcanic unrest scenarios and impact assessment at Campi Flegrei caldera, Southern Italy}   

^{[12] https://www.wtwco.com/en-gb/insights/2023/11/volcanic-risk-and-insurance-the-untapped-potential-of-downward-counterfactual-perspectives}