Kyushu locals, farmers uneasy with volcano's latest eruption

Asahi Shimbun

10-07-2025

The crater of Mount Shinmoedake, captured by a drone around 2 p.m. on July 3. Experts are watching closely to see if eruptions will expand further in the future. (Provided by the National Institute of Advanced Industrial Science and Technology's Geological Survey of Japan)
Since Mount Shinmoedake began erupting on June 22, experts are continuing to closely monitor the southern Kyushu volcano in the event the volcanic activity veers from past flare-ups.
At 1,421 meters tall, this member of the volcanic Kirishima Mountain Range sits on the border between Miyazaki and Kagoshima prefectures. A 5,000-meter plume was observed on July 3.
"The ashes fell from the sky silently as if they were snowflakes," a 70-year-old resident of Kirishima, Kagoshima Prefecture, observed that same day.
According to the Japan Meteorological Agency, ash fell in such large amounts that white lines on roads in Kirishima became obscured, and very loud rumblings were heard in Kobayashi, Miyazaki Prefecture.
Venturing outside at around 10 a.m. on July 4, the Kirishima resident saw that the mountains, grass, flowers, roads and roofs were all stained gray, as if cement had been poured over the entire area and all colors lost.
She shared that the road was covered in 2 to 3 centimeters of ash, her shoes leaving tracks as though she were walking through snow.
Subsequent rain would wash away the ashes and restore the road's colors. However, the bottom of the nearby river turned gray, and the ash remaining on the road hardened into a muddy substance, the woman said.
Although she has not felt any physical changes, she sighed, and said, 'How long will it last? I'm worried about my future life.'
'FIST-SIZE CINDERS' LAST TIME
The JMA confirmed that the volcano is still active, warning that there is a risk of cinders and pyroclastic flows within 2 to 3 kilometers of the crater.
It also cautions residents in other areas to prepare for the possibility that shock waves from an explosion could break windows.
Mount Shinmoedake has had volcanic activity and eruptions from ancient times.
When it erupted in 2011, the JMA's volcanic eruption prediction liaison committee described the event that disrupted transportation and agriculture as the volcano's 'first full-scale magma eruption in 300 years.'
The latest eruption is the first in seven years, and experts are meticulously watching to see if its activity is different from previous ones.
The estimated total volume of ejecta over the six-day phenomenon back in 2011 was 50 million tons. This is about 10 times what Mount Sakurajima spews annually with an estimated volume of 5 million tons of ejecta in a normal year.
According to the Cabinet Office and other organizations, shock waves broke many windows and automotive glass. Fist-size cinders, meanwhile, destroyed solar panels.
The ashfall was particularly disruptive to vegetable harvests over an area of about 12,000 hectares.
FLIGHTS CANCELED, CROPS COVERED
This time, the National Institute of Advanced Industrial Science and Technology (AIST) based in Tsukuba, Ibaraki Prefecture, has conducted a field survey of Mount Shinmoedake.
According to the AIST, gray volcanic plumes are spouting vigorously from a newly formed line of vents in the southeastern part of the crater. There is a chance this line of vents generated pyroclastic flows, the AIST said.
'It is almost certain that there is a new supply of magma.' said Isoji Miyagi, chief researcher of volcanology at AIST's Geological Survey of Japan.
Magmatic eruptions like this are accompanied by the potential of prolonged or large-scale eruptions.
'Even if the activity temporarily ceases, there is a possibility that a larger eruption will occur later, so we need to be careful,' said Miyagi.
The researcher and his team are not taking this lightly. He added, 'At this point, we cannot say how long it will continue, but we are conducting our research with the possibility in mind that the activity of Mount Shinmoedake may have changed from its previous patterns.'
This year's eruption has already impacted the region.
Ashfall from Mount Shinmoedake caused the cancellation of 139 Japan Airlines flights and 16 All Nippon Airways flights over a three-day period from July 2 to 4. Flights were mainly to and from Kagoshima Airport in Kirishima.
The Japan Agricultural Cooperatives Miyazaki's Kobayashi district headquarters reported that crops have also been affected.
Echoing the Kirishima resident, Kiminori Higashi of the headquarters in Miyazaki Prefecture said, 'I'm worried about the future.'
Cucumbers and bitter melons are currently in the harvest season.
Higashi is concerned that washing ash off of the vegetables may not be completely effective or result in discoloring.
(This article was written by Ryo Sasaki and Kenta Iijima.)