When the next eruption occurs it is suspected that the lava stuck in the dome will cause a catastrophic reaction.
The Kikai volcano last erupted 7,300 years ago and is believed to have wiped out the prehistoric Japanese Jomon civilisation.
There are concerns it could soon be set to explode again.
They added that there was a need for “preparation for the next super-eruption”.
There is concern that the next time the volcano overflows, it could send masses of debris into the atmosphere and block out the sun in some areas.
The lack of sunlight would cause what the paper has dubbed a “volcanic winter”.
An alarming part of the study also warned any eruption could cause a tsunami that would wreak havoc in southern Japan and the coasts of Taiwan and China.
It also warned the coasts of North and South America would be hit.
The lava dome was created after the last major eruption when the volcano’s structure collapsed in on itself.
However, the lava dome is rising and could soon hit surface level, when an eruption would be most likely.
It is currently just 30.5 metres beneath the surface.
Intrusions on the surface of the dome have led the scientists to believe that lava is slowly building up beneath the dome.
Since KOBEC was set up it in 2015, three explorative surveys have been carried out on Kikai.
Active gas bubbling and super-heated water columns were also spotted during the investigations.
Explaining the risk of the volcano causing wide-spread chaos Professor Yoshiyuki Tastsumi, head of KOBEC, said: “Although the probability of a gigantic caldera eruption hitting the Japanese archipelago is 1 percent in the next 100 years, it is estimated that the death toll could rise to approximately 100 million in the worst case scenario.”
Japan sits within the Ring of Fire which is well known for its volatile tectonic and volcanic activity.
Around 90 per cent of the world’s earthquakes take place in the region, while the geological zone is also home to more than 450 volcanos.