Vulcanoes are vents in the earth’s crust through which pent-up energy and molten material is released from the interior. Deriving their name from Vulcan, the Roman God of Fire, volcanoes have been treated with awe and respect over human history. With their explosive energy and fiery antics they are the poster-child of books and media related to Planet Earth, ‘natural’ disasters and incredible adventures. My first encounter with these shapers of the earth was in Hawaii. It was there that I fell under the spell of Pele, the Hawaiian Goddess of Volcanoes – one of many gods associated with volcanoes around the globe. Created by passing over a submerged volcanic hotspot, both the Hawaiian Islands and the Galapagos are testament to the constantly moving nature of the earths surface. On land the Pacific ‘Ring of Fire’ exemplifies the clustering of volcanoes along the boundaries of mobile tectonic plates. While fire and volcanoes are synonymous, the elements of water, air and earth also play a fundamental role in the birth and expression of these conduits of energy. The creation, impact and flow-on effects of volcanoes on our lives makes a fascinating and sometimes surprising story.
Of the 600 or so active volcanoes in recorded history, around 20 are erupting at any given time. In 2018 the Kilauea Volcano in Hawaii and Mt Agung in Bali attracted the world’s attention, largely because of their impact on people’s homes, livelihoods and travel plans. Kilauea is the most active volcano in Hawaii. It’s most recent eruption began in the East Rift Zone on May 3, 2018 and paused in early August. Earthquakes and volcanic activity are often linked and Kilauea is no exception. A 5.0 magnitude earthquake occurred before the eruption on May 3rd and a 6.4 magnitude earthquake followed on May 4th. The United States Geological Survey (USGS) reported these were related to the eruptive events. A number of vents and fissures opened on the lower slopes of the volcano releasing flows and fountains of lava that destroyed homes and other infrastructure on Hawaii’s Big island.
Many Native Hawaiians continue to revere Pele, seeing her as the primordial force that created and inhabits all the land in Hawaii. Offerings were made to her during the 2018 eruption and the uncertainty associated with her ‘dance around the island’ accepted. Similar offerings were made to Mt Agung in Bali during the eruptions that started in November 2017. Here it is Siwa, the Hindu God that represents the element of wind, that resides at the top of the volcano. In both Hawaii and Bali it was felt that the goddess and god were angry with the way their islands were being treated. The eruptions were ways of demonstrating their displeasure. In Bali the disruption to the tourist trade was considerable, one of the ways the impact of volcanic eruptions has changed in modern times.
Vulcanologists are scientists who study the processes involved in the formation and eruptive activity of volcanoes, past and present. They bring a different perspective to the understanding and appreciation of volcanoes, one that generally dismisses belief in deities such as Pele and Siwa. Instead Vulcanologists use a raft of measurements, models and observations to monitor and increase the capability of predicting a volcanic eruption. A subset of these scientists visit the craters of active volcanoes, a dangerous and sometimes deadly profession. Stanley Williams, who wrote ‘Surviving Galeras‘, lived to tell the tale of how he survived a volcanic explosion when he was in the crater. Some of this colleagues were not so fortunate.
Sometimes volcanoes surprise and educate vulcanologists by erupting in an unexpected way. Such was the case in 1902 when a large cloud of hot gas and volcanic debris rushed down the side of Mt Pelee on Martinique killing 30,000 people in its path. This newly observed phenomenon was dubbed a “nuée ardente” meaning glowing or burning cloud. In modern terminology, this mix of hot gas and rock is classified as a type of pyroclastic flow, examples of which have since been observed during other volcanic eruptions, including Mount St. Helens in 1980. In some cases ice, water and mud can mix with the hot gas and volcanic rock as it is expelled. An elemental concoction indeed.
Another surprise associated with the 1902 eruption of Mt Pelee was the impact it had on the final location of the Panama Canal. At the time of the eruption both Nicaragua and Panama were being considered for the location of the canal that would connect the Pacific and Atlantic Oceans. Panama was chosen, in part it is argued because of the campaign against Nicaragua being unsuitable because of the 12 volcanoes found there. Pelee was said to be a “terrible object lesson” and that Nicaragua was a “volcanic menace”. The intense lobbying at the time appeared to have paid dividends.
Other strong words have been used to described volcanoes and related earthquakes, with the book ‘raging planet‘ by Bill McGuire referring to them as tectonic threats to life on earth. His is one of 35 books I have collected on volcanoes as I scanned the bookshelves of second-hand shops. As can be seen below, erupting volcanoes are the poster-child of books on Planet Earth, natural disasters, incredible adventures and more.
Kits to make volcanoes, educational toys aimed at boys, are popular. This is understandable when volcanoes both explode and are associated with the lair of villains in movies such as James Bond and Ninjago. Volcanoes are also featured in School Project Packs, as shown below.
Accepting Hector for who he is could be a metaphor for accepting volcanoes for what they are – one of the powerful planetary forces that has shaped Earth and will continue to do so. I prefer this to the portrayal of volcanoes and other natural phenomena in the Reader’s Digest book ‘when nature turns nasty‘. Living with volcanoes is something that over 500 million people face on a daily basis, being close enough to be in danger when an eruption occurs. Working out ways to reap the benefits of volcanoes such as the nutrient rich soils they produce, while having mitigation and evacuation procedures in place, seems a prudent approach.
Sakurajima is one of 16 volcanoes worldwide that have been named ‘Decade Volcanoes’. These have been identified as particular worthy of study in light of their history of large, destructive eruptions and proximity to populated areas. The Decade Volcanoes project encourages studies and public-awareness activities at these volcanoes, with the aim of achieving a better understanding of the volcanoes and the dangers they present, and thus being able to reduce the severity of their impact. As described in the Wikipedia article, the program has had its ups and downs. Overall however it is reported that studies at many volcanoes have led to a clear reduction in the risk faced by nearby settlements, including Seattle in the USA where nearby Mt Rainier poses some danger. There is also a better understanding of the processes underpinning volcanic eruptions such as the importance of water in driving the eruptions of the Taal volcano in the Philipines.
Managing the impacts of volcanoes at a local scale is one thing, eruptions that affect the global climate is another. A striking example of this phenomenon occurred in 1815 after the eruption of Mt Tambora in Indonesia. The ash from the eruption column reached the stratosphere at an altitude of more than 43 kilometres. It dispersed around the world and lowered global temperatures, in an event sometimes known as the ‘Year without a Summer’ in 1816. This brief period of significant climate change triggered extreme weather and harvest failures in many areas around the world. It is also said to have influenced the colour of the sunsets captured by JMW Turner in his paintings and the Mary Shelley’s writing of Frankenstein during the ‘year of gloom’. While these artistic and literary associations are fascinating, the main impact of the eruption was widespread devastation. If a similar eruption occurred today it would cause severe and ongoing disruption to airline travel. The recent eruptions in Bali (Mt Agung 2017) and Iceland (Grimsvotn 2011), referred to earlier, demonstrate some of the potential impacts.
There is so much more that could be said and illustrated about volcanoes. A whole post could be written about Iceland for example – an island created by 130 volcanic mountains. It’s creation, history, geology, geothermal energy and volcanic eruptions are enthralling. It is one of the few places on earth that you can stand between two tectonic plates on land, and see a recently created volcanic island – called Surtsey and named after an Icelandic God of Fire. There are many other expressions of our active earth to explore in Iceland as well. What a marvellous elemental story.
For now I will leave you with a map of the ‘Ring of Fire’ where 452 volcanoes are found, accounting for more than 75% of the world’s active and dormant volcanoes. It is also where hundreds of millions of people live. As the human population grows the interactions between people and the elemental energy of volcanoes is bound to increase.