In 1949, a Dutch scientist made a great discovery as he walked around hitting rocks on the hillsides over a large and beautiful lake called Toba.
The approximately 100 kilometer long lake is located on one of the world’s largest islands – Sumatra in the country Indonesia. Lake Toba is up to 500 meters deep and covers an area as large as twice Bornholm in Denmark.
The scientist’s discovery was that the mountain slopes are filled with a certain kind of rock that can only form when lava from volcanoes gets cold and solidifies. Lava is the fiery and bubbling ‘porridge’ of molten rock that erupts from the Earth’s hot interior when volcanoes erupt.
Today we know that Lake Toba is the world’s largest volcanic lake. And we know that the entire lake – and all the mountains that surround it – were created during the greatest natural disaster on Earth in the last at least 100,000 years.
It is also possible to argue that it is without a doubt the worst that our human ancestors have ever experienced.
It happened some 75,000 years ago, and many huge earthquakes must have rumbled and rocked the earth in the days and hours leading up to it.
Initially, the eruption particularly affected the island of Sumatra, where huge areas were covered with lava, soot and ash at a depth of up to 400 meters. Thus, all plants and animals at a distance of several hundred kilometers from the volcano were buried for time and eternity.
But then there was the ash cloud, which was so large that it must have turned day into the darkest night over large parts of Asia. In southern India, more than 2,000 kilometers from Toba, a layer of ash several meters thick can be found from the eruption. Yes, even in a lake in southern Africa as far as 7,000 kilometers away, ash remains from Toba have been discovered.
High in the atmosphere, ash and gases from the volcano were carried around the globe by the winds. Thus a veil was made, which blocked a very large part of the sun’s rays, and then it became otherwise cold. Teething cold.
Today it is believed that the temperature dropped by ten degrees on average worldwide – and that it took several years before the volcanic fog eased and the temperature rose again. This is called a volcanic winter – a winter of several years created by a volcanic eruption.
Seen over a whole year, the average temperature in Denmark is eight to nine degrees. This would mean that if a supervolcano like Toba explodes in the air today, the temperature would drop to around minus two degrees on average in Denmark.
Summer would feel like cold autumn, spring and autumn like really cold winter and all winter like the bottom of a freezer.
According to the journalists, “People who looked like you and I – without clothes on – originated in Africa about 300,000 years ago. But it was not until about 100,000 years ago that they began migrating out of Africa to conquer the world. And the first place they went was towards Asia.”
So there were certainly people near the current Lake Tabo when the volcano exploded – and the volcanic winter occurred.
One can only guess how it affected our ancestors at the time. But a reasonably good guess is that when the heat returned several years after the eruption, there were only a few thousand people left in the entire world. Maybe only 5,000.
In other words, we had become an endangered species because of the Toba volcano. Completely like today’s tigers, rhinos and blue whales.
And if it is true that there were only 5,000 people left, all of today’s nearly eight billion people are descendants of the very few cool survivors of that time. You and I too.
Image Credit: iStock
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