• Peter Barakan


    Born in London in 1951, Peter earned a degree in Japanese from the University of London's School of Oriental and African Studies (SOAS). An expert on diverse forms of popular music, Peter is also a well-known TV and radio presenter. He has lived in Japan for 40 years and has a deep understanding of the language and culture.

  • Matt Alt


    Born in Washington D.C. in 1973, Matt's interest in Japan was kindled by robot toys in his childhood. He worked as a translator for the U.S. Patent and Trademark Office before co-founding a company that produces English versions of Japanese comics and video games. He also writes extensively about cultural trends including yokai, ninja, emoji, and more.

  • Hiroki Kamata

    Main guest

    A professor at Kyoto University, Hiroki Kamata specializes in the fields of geology, volcanology, and science communication. Alongside his own scientific research, he is active in his efforts to raise popular awareness of the latest findings about volcanoes. Kamata has written numerous books on subjects such as Japanese society’s long coexistence with seismic and volcanic phenomena, along with the knowhow needed to survive in such an environment.


September 29, 2016


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Japan, as most readers will already be aware, is an island nation affected by particularly high levels of seismic activity. Sitting at the convergence of four tectonic plates, not only is the country famously prone to earthquakes, it is also thought to be home to around 7 percent of the world’s active volcanoes.


Yellow lines show tectonic plates, and each red triangle shows an active volcano.

There are dozens of active volcanos (any volcano that has erupted in the last 10,000 years) and numerous other dormant peaks.

The very word for volcano in Japanese, “kazan” (fire mountain), conjures up all sorts of dramatic associations. And high-profile disasters such as the eruptions of Mt. Ontake (2014, 58 deaths) and the Fugen peak of Mt. Unzen  (1991, 43 deaths) may be enough for some to question the wisdom of living in close proximity to these capricious natural features. 

Japan’s annual death toll from volcanoes, however, pales in comparison to more prosaic accidental killers like suffocation and choking (9,662 deaths in 2014 according to the Ministry of Health, Labour and Welfare), drowning (7,490), falls (7,454), and traffic accidents (5,626).

In contrast, Japan’s deadliest volcanic incident of the twentieth century -- when an eruption of Hokkaido’s Mt. Tokachi melted snow which triggered massive mudflows -- resulted in the loss of 144 lives.

That is not to trivialize the amazing power of volcanoes. The economic ramifications of a major eruption can also be very serious, with disruption to industry and infrastructure, and destruction of crops. And greater death tolls over the last half-century have only been averted by Japan’s sophisticated seismic-monitoring system, which provided sufficient advance warning to carry out large-scale evacuations on the islands of Oshima (prior to an expected eruption of Mt. Mihara in 1986), and Miyakejima (2000, home of Mt. Oyama).

What, then, are the positives outweighing the risks to the extent that people in Japan have historically been content to settle in the areas around these mountains that are potentially so hazardous?

The first and most obvious is the fertile soils produced by falls of mineral-rich volcanic ash. Although a 1914 eruption of Sakurajima killed 30 people, and the mountain continues to churn out ash, lava and other debris on a regular basis, the productive agricultural lands in the surrounding area are more than enough incentive for people to stay.


One crop made possible by the mineral-rich Kagoshima soil is the Sakurajima daikon radish.


Sakurajima daikon

And in mountainous Japan, areas of flat land suitable for intensive settlement have historically been at something of a premium. Many of the most inviting areas were themselves created by volcanic flows and ash falls, including the Kanto Plain, site of such major conurbations as Tokyo, Yokohama, Saitama, and Kawasaki.

The eruption of Mt. Fuji in late 1707 lasted several weeks and shrouded much of the Kanto plain in a dense cloud of ash, including what is now Tokyo, some 100 km away. But the resulting fertile soils were ultimately a boon for those living in the region. As expert guest, volcanologist Hiroki Kamata sums up: “The peak of the disaster lasted only two or three weeks, but people saw benefits lasting 300 years.”


Mt. Fuji itself erupted in 1707.


Just over 300 years ago, a major eruption of Mt. Fuji scattered ash across the Kanto Plain, and farmers continue to benefit from the resulting fertile soils.

And there are other economic benefits in the form of tourism. Locations such as Sakurajima, along with Hakone (Kanagawa Prefecture), and Tsumagoi (Gunma Prefecture) draw many thousands of tourists each year to witness volcanic activity close-up.

Many locations have also taken advantage of the resulting hot springs to set up lucrative onsen resorts. Down the centuries, a relaxing soak in a volcanic bath has become a favorite pastime of the Japanese themselves and many visitors to the country.


Vents spewing sulfurous gas cover the valley walls of Owakudani, in Hakone, near Tokyo.


One popular Owakudani treat is a boiled egg, whose shell is blackened by the onsen waters in which it is cooked.

And as long as the risks are properly managed through ever-improving early warning systems, volcanoes might actually be the gift that keeps on giving. One area that is currently underexploited, though currently gathering steam (no pun intended), is geothermal power.

As Japan, like much of the world, looks towards renewable forms of energy, the use of underground magma to produce the steam to drive energy-generating turbines is seen as an area with great potential. The Japanese government has announced plans to treble the nation’s geothermal energy output by the year 2030.


Sakurajima: a dangerous beauty.


The area around Sakurajima is dotted with shelters to help people escape flying debris.


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