People consider themselves omnipotent. They turn the river back, fly into space and descend to the bottom of the ocean. But this is just an illusion. We remain defenseless in the face of natural disasters. Recently, scientists are increasingly talking about this, predicting the re-eruption of the Toba and Yellowstone volcanoes. How does this threaten humanity? What are the consequences of the eruption of supervolcanoes tens of thousands of years ago? We listen to the opinion of experts.
What is a super volcano?
People can walk on its surface for thousands of years and not be aware of it. You can see the supervolcano only from space. It is a giant hollow (caldera) located at the junction of lithospheric plates. If an ordinary volcano erupts, then supervolcanoes explode. This process can be compared with the impact of a very large asteroid, which brings with it death and severe disasters.
Fortunately, this does not happen often. One of the largest in history was the explosion of the Toba volcano, located in Indonesia on the island of Sumatra. Visually, it is inconspicuous, but its caldera is impressive - 1775 square meters. m. In the funnel formed Lake Toba - the largest of the lakes of volcanic origin. In its middle part is the island of Samosir. It is said to be a resurgent dome. In 2004, seismologists recorded an island shift due to underground tectonic processes. Officially, the volcano is dormant, but it has not always been so.
Why did ancient people die out?
In the 90s of the last century, genetics made a discovery that was a shock to everyone. In the DNA of people living in different corners of the planet, there were too many similarities. Even chimpanzees from different populations had 4 times more differences. The conclusion was drawn from this: we all descended from one or two thousand Cro-Magnons. But why did this happen? Where did the remaining ancestors of people go?
Greenland ice samples explained: the next ice age has begun on Earth. The ash layer of the Toba volcano remained in the ice, it precedes the cooling stage. Other traces of the explosion are found at the bottom of the Bay of Bengal, in India, Asia, China, Africa. All this allowed scientists to conclude about the most powerful eruption of the Toba volcano 70 thousand years ago.
A huge explosion
During the eruption, according to scientists, from 28 to 30 thousand cubic kilometers of magma, 5 thousand cubic kilometers of ash were thrown into the atmosphere. They reached a height of 50 kilometers, after which they settled on an area equal to half of Australia. Sulfur spilled acid rain, ash blocked the sun's rays, causing a "volcanic winter."
The strongest explosion could not but provoke earthquakes and tsunamis in different corners of the Earth. All this lasted about two weeks. Living creatures within a radius of thousands of kilometers died from a blast wave, suffocation and poisoning by hydrogen sulfide. But in remote regions, the consequences were terrifying. It is the Toba volcano, according to some scientists, to blame for the fact that the number of primitive people fell sharply to 1-2 thousand people. In fact, our species faced a grave threat of extinction.
Bottleneck effect
Scientists use this term to explain a reduction in a particular gene pool. It is great for describing what happened to humanity. In ancient times, the human population was distinguished by great genetic diversity. But then, under the influence of external circumstances, the population decreased sharply to a critical amount, which led to the depletion of the gene pool. Many researchers attribute this to the explosion of the Toba volcano.
Disputes about how much the climate has changed since then are still underway. Someone talks about lowering the temperature by a maximum of 3.5 degrees, other scientists insist on a significant cooling in both hemispheres. The numbers are called awesome - from 10 to 18 degrees. If the latter was true, nascent humanity had a hard time. Some experts attribute to that period the death of Neanderthals and the victory of Cro-Magnons, who survived thanks to their minds, over them.
However, excavations in India's neighboring Indonesia show that people still survived. Stone tools are found both before the ash layer of the Toba volcano, and immediately after it. In Africa, the amount of volcanic residues in Lake Malawi is too small; the temperature here fell by no more than 1.5 degrees Celsius.
Be that as it may, but humanity once found itself on the verge of extinction. Is the volcano, asteroid, cold snap or severe drought to blame? It is hoped that nature will be merciful to us, and this will never happen again. And the Toba volcano will forever remain a popular place among tourists, where you can relax in nature.