The most devastating and deadly natural disasters from ancient history

Rendering of a volcanic eruption
The eruption of a supervolcano approximately 75,000 years ago caused the whole of South Asia to be covered by 15cm of ash | Shutterstock

Earth-shattering volcanic eruptions, earthquakes that wipe out whole civilisations, megafloods. They might all sound like the plot of Hollywood's latest catastrophic world-ending blockbuster, but apocalyptic natural disasters have existed a lot longer than humanity. Here are four world-ending events from ancient history that show the true terrifying power of Mother Nature.

The Chicxulub Crater

Buried under the Yukatán peninsula in Mexico, lies the world-famous Chicxulub Crater. The 180km wide and 20km deep natural cavity is the remnant of the impact of an asteroid that crashed into Earth approximately 66 million years ago.

The asteroid is estimated to have been only 10km in diameter, but don’t let that relatively small size fool you. When the asteroid first made contact with Earth, it would have been travelling at astronomical speeds. This led to an extinction-level event that wiped out up to 75% of the flora and fauna of the Cretaceous Era, including all the land-based dinosaurs.

With the equivalent power of more than one billion atom bombs, the shockwaves were felt across the globe. Winds of up to 600 miles per hour stormed out in all directions from the epicentre. Masses of ash, gases, and debris were all thrown up high into the atmosphere, blocking out the Sun, severely dropping global temperatures, and suffocating everything it touched. The debris was also superheated by Earth’s atmosphere before falling back to the ground, starting wildfires and destroying anything in its path.

Youngest Toba Catastrophe

The Youngest Toba Catastrophe is one of many super-volcanic eruptions that have shaped the landscape of Earth. Estimated to have erupted approximately 75,000 years ago, the eruption is believed to have caused a global volcanic winter that greatly affected the evolution of the human race.

Located in Lake Toba, Indonesia, the Youngest Toba Catastrophe was the last and most volatile of the mega volcanic eruptions at the site. 15cm of ash covered the whole of South Asia and could be found as far away as China, the Indian Ocean, and the Arabian Sea.

Experts believe that the eruption caused dramatic cooling across the world. This global volcanic winter may have lasted as long as 1,000 years with the average surface temperature being lower by 3-5°C.

Hydrogen sulphide seas

The Earth lives in a constant state of a delicate balance between plants, animals, and minerals; but what happens when one small shift in that balance ultimately tips the scales? Scientists believe that this is what happened 252 million years ago during the Permian-Triassic extinction event. The seas were turned toxic and the ozone layer was permanently damaged.

It’s hypothesised that global warming upset the balance between photosynthesizing blooming algae in the sea and deep water sulphate-reducing bacteria. This imbalance triggered a steady and swift rise in hydrogen sulphide in the oceans, which was emitted as a toxic gas. As the gas grew in intensity it would have killed anything that it came into contact with and caused severe damage to the Earth’s ozone. This triggered further death and destruction to the wildlife that was exposed to the sun’s radiation.

Zanclean Flood

The Zanclean Flood was a megaflood that refilled the Mediterranean Basin and ended the Messinian salinity crisis. The Mediterranean's access to the Atlantic Ocean has long been determined by the African, Arabian, and Eurasian tectonic plates. At some point between five and six million years ago, tectonic activity closed the Strait of Gibraltar and separated the Mediterranean from the Atlantic Ocean.

This ultimately caused the water levels in the Mediterranean to drop by kilometres, and many areas of the thriving sea were dried up into salt flats. Rivers that relied on the Mediterranean, such as the Nile, were driven deeper to compensate for the dwindling water. Much of the varied sea life that had lived there either dried up or died from the high levels of salinity in the remaining water.

Approximately 5.3 million years ago the wall that had held back the Atlantic Ocean from the Mediterranean broke, and what followed was a catastrophic deluge of water that rapidly refilled the basin. It’s estimated that the water levels rose by as much as 10m per day in some places, and geological areas such as the Strait of Gibraltar and the islands of Greece were created.

It is also believed that the Zanclean Flood is responsible for the speciation (slight evolutionary differences discovered by Charles Darwin) of various creatures found across Mediterranean islands, along with the thriving sea life and crustaceans that have made the area their home.

Written by:

Jo Rowan