HOKKAIDO - Mount Tokachidake in central Hokkaido experienced its first confirmed eruption in 22 years on July 22, sending a column of black smoke about 200 meters above the crater, although authorities said there were no signs that volcanic activity was intensifying.
The very small-scale eruption occurred at around 11:07 a.m., according to the Sapporo Regional Headquarters of the Japan Meteorological Agency.
No large volcanic rocks were confirmed to have been thrown from the crater. However, instruments detected volcanic tremors and an air shock caused by the eruption at an observation point near a mountain shelter.
Cloud cover obscured the summit area, making the plume difficult to see from some locations near the volcano.
Tourists who had visited Bogakudai, an observation area about three kilometers from the crater, appeared unaware that an eruption had occurred.
"Really? I had no idea. That is surprising," one tourist said.
Businesses in the Shirogane Onsen hot spring district at the foot of the mountain were closely watching developments as Hokkaido entered its summer tourism season.
"There has been no impact so far. All we can do now is hope that nothing else happens," said Seitaro Mizuno, representative of the Shirogane Jiyuko Hotel.
The eruption was the first observed at Mount Tokachidake since 2004.
The meteorological agency said it would maintain the volcano's alert level at Level 2, which restricts access around the crater. People have been warned to remain alert for large volcanic rocks within approximately 1.5 kilometers of the crater and not to enter hazardous areas.
Following the eruption, the town of Kamifurano issued information through its disaster-prevention radio system and municipal website.
"We announced over the disaster-prevention radio system that there was no impact on the daily lives of residents living at the foot of the mountain," said Hidehito Tsuji of the Kamifurano town government's general affairs division.
The Sapporo meteorological office said the eruption remained within the range of activity anticipated under a Level 2 alert.
"We have not seen any indications at this time that the activity will intensify further, so we will continue to maintain Volcanic Alert Level 2," said Nagasawa, head of the regional volcanic monitoring and warning center at the Sapporo meteorological office. "People living at the foot of the mountain and in the hot spring district may continue their lives as usual. Hikers should remember that access near the crater remains restricted."
The agency warned that volcanic ash and small volcanic rocks could be carried farther from the crater depending on the wind direction.
The eruption occurred at the 62-2 crater, where Level 2 restrictions had been in place since June. Entry within a radius of 1.5 kilometers was already prohibited before the eruption.
Officials said the restrictions would remain unchanged and that local residents and tourists did not need to be excessively alarmed. No indications of increasing volcanic activity have been observed, and any direct impact is expected to remain within approximately 1.5 kilometers of the crater.
Residents at the foot of the mountain do not need to take heightened precautions at present, but hikers have been urged not to approach the crater area.
Mount Tokachidake is an active volcano standing 2,077 meters above sea level near the center of Hokkaido. The surrounding area includes major tourist destinations such as the Blue Pond, which is especially popular with international visitors, and Bogakudai, where visitors can view the crater during normal conditions.
The volcano has repeatedly erupted at intervals of roughly 20 to 30 years.
Its most destructive eruption occurred in 1926, when part of the mountain collapsed and hot volcanic debris melted snow, triggering a snowmelt-type mudflow. A total of 144 people were killed or went missing.
Another eruption in 1962 left five people dead or missing. Mount Tokachidake also erupted more than 20 times between 1988 and 1989.
Hokkaido has 31 active volcanoes. Nine of them, including Mount Tokachidake, are designated by the Japan Meteorological Agency for continuous 24-hour monitoring and warning operations.
Other continuously monitored volcanoes include Mount Esan and Mount Usu, as well as Mount Meakan, which is also currently subject to Level 2 restrictions.
Source: 北海道ニュースUHB
