Ōwaku Valley, a part of Mount Hakone with high volcanic activity, has been showing more signs of an impending eruption recently. The smoke which regularly issues from its vents was mingled with ash, turning noticeably gray, for about ten seconds around noon on July 21. On June 30 and July 1, it had also erupted on a very small scale, ejecting material to a distance of over 100 meters (328 feet), which technically meets the qualifications for an “eruption.”

(The distance material from the recent eruption was ejected has not yet been measured.) However, tremors associated with volcanic eruptions have not been recorded. According to the Japan Meteorological Agency, “it has the characteristics of an eruption, but that would have an effect on disaster prevention by inciting residents’ anxieties, so the term ‘eruption’ is not appropriate.” MORE