The Sept. 27 eruption of Mount Ontake — where the search for missing climbers has been suspended until spring after 56 people were confirmed dead — has triggered calls for beefing up the system for monitoring volcanoes around the country as well as emergency protection of local residents and climbers.
These measures also need to be accompanied by people’s increased awareness of the risk from volcanic eruptions — which, as the latest disaster reminds us, could happen anytime without many warning signs.
While the eruption of the 3, 067-meter mountain resulted in the largest number of casualties from a volcanic disaster since 1926, it was a relatively minor eruption in volcanological terms. But it hit at the worst time.
The area near the peak was crowded with about 300 climbers who had come to see tinted autumnal leaves on a sunny weekend, when it suddenly erupted just before noon.
Prior to the disaster at Mount Ontake, no one had been killed in volcanic eruptions in Japan since 43 lives were lost in the pyroclastic flow from Mount Unzen in Nagasaki Prefecture during its 1991 eruption. Residents were evacuated in advance of major eruptions of Mount Usu in Hokkaido and Mount Oyama on the Miyake Island in the Izu Island chain. Both eruptions were in 2000.
There have been eruptions of other volcanoes in recent years that did not result in casualties simply because nobody happened to be around the peak, including the March 1996 phreatic explosion at Mount Komagatake, in southern Hokkaido, that shot up volcanic ash and cinders just like in the case of Mount Ontake.
The latest disaster served as a reminder that volcanoes can erupt unexpectedly. A phreatic explosion like the one that hit Mount Ontake, which is caused when magma heats up groundwater and triggers instantaneous evaporation, is said to be hard to forecast by observing changes in geological data.
Prime Minister Shinzo Abe has told the Diet that the government would step up the monitoring of volcanoes around the country, and the Meteorological Agency’s Coordinating Committee for the Prediction of Volcanic Eruptions plans to compile a report reviewing the current monitoring system by the end of March.
Lawmakers in the ruling Liberal Democratic Party have called for budgetary allocations to beef up the nation’s volcano studies and to increase shelters to protect climbers when there are eruptions. Such efforts appear long overdue in a country where 7 percent of the world’s active volcanoes are concentrated.
There are only about 40 researchers at state-run universities across Japan who engage in the observation and forecasting of volcanic activities.
Still, the knowledge and information obtained through the studies and observations are of no use unless they are appropriately shared by local municipalities, residents and visitors.
Of the 47 volcanoes that are subject to round-the-clock monitoring, hazard maps highlighting vulnerable areas in case of eruption have been prepared for only 37 as of last March.
Of the 130 municipalities that could be affected by eruptions of the 47 volcanoes, only 20 have prepared specific evacuation plans.
Climbers to the tops of volcanoes should be made aware that the risk of eruptions is always there. Dissemination of information to climbers concerning volcanic activity for each mountain and basic knowledge about volcanoes is deemed insufficient.
Many of the nation’s volcanoes draw large numbers of visitors for their scenic beauty, hot springs and other attractions. A deep-seated reluctance appears to linger in the tourism industry toward highlighting the dangers of volcanic eruptions, out of concern that such information could discourage visitors.
The Hawaii Tourism Authority’s website updates news about volcanic activity on the island of Hawaii, including information about possible dangers to visitors.
At Mount Ruapehu in New Zealand, which is well-known as a ski resort, pocket-size hazard maps are reportedly distributed to tourists.
At Mount St. Helens in Washington State of the United States, the site of a catastrophic eruption in 1980 that killed 57 people and destroyed many houses, bridges, and stretches of railways and highways, visitors can be fined for walking outside the designated hiking path. Documents and picture books detailing the records of eruptions are made available at local gas stations.
Local authorities around Japan’s volcanoes could start by following these examples.
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