Agung volcano on Bali island of Indonesia.
Agung's latest eruption was in 1963, causing a terrible disaster, killing more than 1,000 people.
Authorities had to evacuate about 75,000 people in dangerous areas around the Agung volcano to prevent an imminent disaster, just a moment.
Scientists warn that when Agung volcano erupts, a large amount of ash and SO2 are pumped into the atmosphere. SO2 then reacts with air vapor to form sulfuric acid. About 10 million tons of sulfuric acid will accumulate in the stratosphere and act as a barrier to reduce the amount of ultraviolet rays shining on the ground and make our planet colder. The Earth's temperature will drop to about 0.4 degrees.