The recent eruption at Mount Moto-Shiranesan, one of the three Kusatsu-Shiranesan peaks in Kusatsu, Gunma Prefecture, left one person dead and 11 injured.

The Japan Meteorological Agency designates 111 mountains as “active volcanoes” and monitors 50 of them around the clock with seismometers and instruments for measuring angles of elevation or depression, along with wide field-of-view cameras.

Mount Kusatsu-Shiranesan is on the watch list.

But the phreatic eruption, a steam-driven explosion, occurred at a peak outside the monitoring program. Clearly, a close watch is needed for any explosive emissions of cinders and volcanic gases from the site.

Unexpected eruptions can occur anywhere in Japan.

Volcanologists are hardly able to predict precisely when, where or how volcanic eruptions will occur, especially relatively small events like the explosion in Kusatsu.

Due also to budget restraints, the monitoring and surveillance network to keep track of volcanic activity is far from perfect.

It is impossible to predict even earthquakes, which occur far more frequently than volcanic eruptions, despite the availability of huge pools of seismological data and other studies.

In addition, we have not forgotten what a working group of the government’s Central Disaster Management Council acknowledged last summer: that it is impossible to predict the long-anticipated Tokai Earthquake, which is assumed to strike off the Pacific coast of central Japan. This represented a radical shift from the long-held position that such event is predictable.

With regard to volcanic eruptions, it is all the more important for us to confront the reality that we need to brace for unexpected events and take measures to mitigate damage based on this assumption.

The government worked out an outline of measures to this end after Mount Ontakesan erupted in 2014, leaving 63 people dead or missing. The volcano straddles Nagano and Gifu prefectures.

The law has also been revised to promote measures to protect climbers as well as local residents when eruptions strike.

The revision has made it mandatory for local governments in areas at risk to develop plans for emergency evacuations in response to eruptions. But only one-third or so of the 155 municipalities that are home to volcanoes under constant monitoring have crafted emergency evacuation plans.

Municipalities that have yet to take action should do so quickly as evacuation plans are fundamental elements to any emergency response.

Given what happened at Mount Kusatsu-Shiranesan, it may be smart move to expand areas around volcanic craters assumed to be at risk.

In that case, resorts near volcanoes that are popular with climbers and skiers may be put on the list of hazardous areas.

Priority must be given to building shelters and other structures at such resorts to protect people from debris and gases spewed out in an eruption.

Volcanoes are a valuable tourist resource, offering beautiful landscapes and hot springs.

Local governments that capitalize on these attractions to draw tourists must be responsible for taking all possible measures to protect visitors.

The central government provides financial support for these endeavors and low-cost methods of building such protective structures are being developed.

Local governments in areas near volcanoes should be flocking to adopt such safety steps.

But other more serious problems exist.

Many local governments trying to mitigate damage from volcanic disasters lament the dearth of expertise on the issue.

Despite being a volcano-studded country, Japan has only a very limited number of researchers in related areas.

In the aftermath of the devastating eruption of Mount Ontakesan, the government stepped up policy efforts to develop the human resources.

Steady funding is needed to expand the pool of experts at universities and research institutes.

Mother Nature is warning us to redouble our efforts to be better prepared for volcanic eruptions.

--The Asahi Shimbun, Jan. 27