Sakurajima eruption "If you could see a volcanic block, you were on alert level 5" Meteorological Agency Information June 12, 19:52
It was confirmed four days after the eruption that large volcanic blocks flew beyond the warning range and near the residential area on Sakurajima in Kagoshima City, but the Japan Meteorological Agency said that this eruption did not reach the warning level 5. However, on the 12th, the explanation was corrected, "If the volcanic block could be confirmed immediately after the eruption, it was raised to level 5."
The Japan Meteorological Agency originally announced by surveillance cameras that the explosive eruption of Sakurajima had occurred on the 4th of this month on the 4th of this month, and the distance of the large volcanic block was within the warning range of 2 kilometers from the crater. In fact, four days after the eruption, it was confirmed that it had flown to a point approximately 3 kilometers from the crater.
The place where it fell was only about 100 meters away from the village, and there was also a hole in the roof of the nearby material storage area that could be attributed to a part of a volcanic block.
According to the criteria for eruption warning level of Sakurajima announced by the Japan Meteorological Agency, if "a large cinder is scattered more than 2.5 km from the crater", it will be raised to level 5 indicating evacuation, but the Volcano Division of the Japan Meteorological Agency says It means that a lot of volcanic blocks fly, and this eruption was one volcanic block, so it doesn't correspond to level 5."
Local residents and experts questioned this view, but the Japan Meteorological Agency's Volcanic Division told NHK on the 12th that "one volcanic block was considered to be scattered, and again this time it was immediately after the eruption. If I was able to confirm it, I was raised to level 5."
Regarding the reason, he said, "Because it was not in the situation to raise the level already, I explained it differently from on-site operation."
On top of that, he added, "I could not confirm the volcanic block with a surveillance camera this time, but I would like to study the improvement of technical accuracy in the future."