In the quiet, beautiful area of Southern Japan just on the edge of Kagoshima, sits the Sakurajima volcano. Underneath this beautiful, picturesque area lies a hidden danger – a danger that could cause the end of humanity. The end of civilization as we know it. That is because it is part of the beautiful, dangerous, and beautifully dangerous Aira caldera. That is because a caldera is more commonly known as a supervolcano!
A supervolcano is any volcano that is capable of producing an eruption greater than 1000 km2 of magma. There are relatively few areas in the world capable of producing such powerful volcanic eruptions, but one of them just happens to be in Southern Japan.
It is estimated that there might have been at least 10 of these supervolcanic eruptions in the earth’s history, but most of these happened before humans existed. The most recent supervolcano to erupt was at Lake Toba in Indonesia over 75,000 years ago. It blasted 2,800 km2 of ash and magma into the air.
Using the Lake Toba eruption as a base, some scientists project that such an eruption could cause a volcanic winter. So much ash would be blasted into the atmosphere it would cause and “anti-greenhouse” effect, in which the ash blocks out the sun and causes global temperatures to drop precipitously. This is very similar to nuclear winter, but without the radiation.
This has happened before. In April 10, 1815, Mt. Tambor erupted, causing the following year of 1816 to become the “year without a summer”. If Aira erupted it would cause massive devastation in the immediate area. Basically, one supervolcano eruption would have the force and power of hundreds of the most powerful nuclear bombs going off at the same time, in the same place. It could cause billions of deaths worldwide due to the immense climate shifts that would cause crop production to fail and massive starvation.
In such an environment, governments would collapse, anarchy would reign, and dogs and cats would live together. If you have ever played the video game series Fallout you can imagine it being very similar.
However, don’t worry… too much. As scary as this all sounds, you don’t have to keep looking over your shoulder at the Aira caldera, most scientists agree that the chances of Aira wiping human civilization off the map are very, very low.