When a Volcanic Apocalypse Nearly Killed Life on Earth
The next time someone asks you why global warming is such a big deal, answer with three words: The Great Dying.
And if your friend is confused by your apparent reference to some kind of European heavy metal band, explain to them that the Great Dying is the largest destruction of life on earth that we currently know of, and has nothing to do with German guys screaming about death.
The end-Permian mass extinction, which occurred around 252 million years ago, has been a source of interest and confusion for geologists since its discovery. In a pretty short period of time, over 70% of vertebrates and 90% of marine life went completely extinct, and every life form on earth was permanently disrupted. It caused major evolutionary change in all species, a shift more dramatic than any other that we’ve seen.
So what caused it?
There are quite a few theories on the cause of The Great Dying, the most accepted of which is the volcanic eruption theory. When it was discovered that the volcano formation the Siberian Traps were formed not in the previously thought 10-50 million years but instead only 1 million years that lined up perfectly with the sharp decline of life on Earth, evidence began to point toward the Siberian Traps as the cause of the destruction.
So how does this tie in to global warming?
When volcanoes erupt, they emit incredibly huge amounts of CO2 gas, the gas responsible for messing with our earth’s natural sunscreen (the ozone layer), the gas we are producing on an unprecedented scale.
It also produced sulphur dioxide, another ozone depleter. And when the Siberian Traps erupted, they produced five million cubic kilometres of lava, enough to cover the earth’s surface to a depth of about ten meters.
The damage wasn’t just contained to the land: the global temperature rise also depleted our oceans of oxygen, killing organisms as far down as the ocean floor from oxygen deprivation.
The increased CO2 in the atmosphere also contributed to high levels of ocean acidity, which keeps sea creatures from being able to build their shells, and further contributed to their extinction during the Great Dying.
Jonathan Payne, a geologist who specialises in mass extinctions at Stanford University, remarked: “The biggest extinction event we have in the history of life has a lot in common with the environmental changes occurring today and that we anticipate in the next 100 to 1,000 years.
In fact, in the long run, it had a stimulating effect on ecosystem diversity, but the recovery took millions of years to kick in, so loss of diversity is not something that should be thought of as useful or relevant to human society.”
So when your friend asks you about global warming, let them know why it’s so important: because we don’t want 90% of our life system extinct again.