In the last post we shortly discussed a new research regarding the sixth extinction episode . In this one we shortly discuss a newly published book by Peter Brannen about the 5 previous mass extinction episodes called “The Ends of the World”.
The book tells the story of the five biggest mass extinctions, and what can be learned from them about the current one. Obviously the target audience is not activists and supporters of the E.A.S movement , but it is very relevant for us.
We started this blog soon after a wave of false headlines of a giant asteroid coming towards earth, about 2 years ago. Not because it didn’t wipe out the planet or at least humans (although animals’ hurtfulness is incomparable to humans’ hurtfulness, they are still part of the problem as you can see here and here), but because we encountered so many comments, from activists all over the world, who for several days kept sharing their wishes for the planet to be wiped out, and their disappointment when it didn’t.
The current state, which is that the most caring humans in the world, those who devote their lives fighting for the most helpless beings in the most oppressive systems, are passively waiting for something extraordinary to happen, an uncontrollable factor that would save the billions of victims per year, must change.
Most activists are hoping for a planetary scale miracle while working on tiny changes in tiny scopes of action (compared with the global oppressive mechanism). The fact that the problem is so immensely huge that it’s almost impossible to really comprehend, leads too many activists to passively think big but actively work small. We want to change that so activists would think huge and act huge. Think global and act global.
Obviously animal liberation activists wishing for the planet to be wiped out, is not new. Many activists say they would press the button when asked the hypothetical question, but very few are willing to dedicate their lives to create such a button. Very few are willing to stop focusing on their tiny dot of influence, to stop looking for ways to make a few more vegans and start looking for ways to stop all of the oppressors from causing all of the suffering.
When most people think about extinctions they think of epic sudden events like giant asteroids or comets, gamma radiation, biblical scale tsunamis and massive lava eruptions, and even a black hole sucking the planet whole, but not of changes in the global carbon levels.
The most famous extinction event happened in The End-Cretaceous about 66 Million Years Ago and is mostly known as the dinosaurs extinction. The chapter dedicated to that mass extinction episode (each chapter focuses on one) broadly details the academic dispute over the causes of the episode as the common conception outside the scientific community is that the dinosaurs were spectacularly wiped out by a 10 kilometer wide asteroid that hit in Mexico.
But more recent research indicates that global warming and ocean acidification, triggered by volcanism in the Deccan Traps in India (that would have been enough to cover the entire lower forty-eight United States in 600 feet of lava), were the true causes.
In brief, it is very unlikely that an asteroid hit leaving a crater of 150 to 170 kilometers, caused mass extinction while other asteroid hits leaving craters of 100 to 120 kilometers did nothing even remotely close. On the other hand there are very decisive evidences of CO2 driven swings in climate, deciphered from the isotopes of fossil plankton pulled up in drill cores from the deep ocean in several locations. Rapid warming spikes of 4 to 5 degrees Celsius in the ocean and as much as 8 degrees on land, that took place in under 10,000 years, decimated life.
Oceans acidification is evidenced by the dwarfed species of plankton during thousands of years after the extinction, as well as organisms’ shells which became smaller and simpler.
And finally based on fossil plankton in rocks, some scientists date the extinction long after the asteroid impact and thus could not have been caused by it.
Later on, a combined theory was suggested, meaning that the impact caused an earthquake which triggered the Deccan Traps in India which as aforesaid caused the climate change that led to the extinction.
And the same goes for the other mass extinctions, they are all associated with dramatic changes to the climate and the ocean, driven in most cases by the forces of geology itself.
Even the mass extinction event in the end of the Ordovician, 445 million years ago, was a result of a dramatic and rapid (in geological terms) decline in the carbon dioxide levels as result of wild swings in the carbon cycle which eventually chilled the planet to a deep freeze.
The dedicated chapter details how and why carbon is so crucial in extinction events. Here is the Carbonate-silicate cycle (taken from the chapter):
“Carbon dioxide reacts with rain to make it slightly acidic. This slightly acidic rain lashes rocks over millions of years, breaking them down and washing stuff like calcium out into the rivers and, eventually, into the sea. This carbon- and calcium-rich broth is then incorporated into the bodies of living things like sponges, corals, and plankton. These creatures then bury the carbon at the bottom of the ocean as calcium carbonate limestones. Visit your favorite monument or building made of limestone and take a closer look—the stone is simply the detritus of living things. This is how carbon dioxide from the atmosphere is converted to rock and safely stored away in the earth. Eventually this process might dangerously drain away the atmosphere’s blanket of carbon dioxide that keeps the planet habitably warm. But this doesn’t happen because carbon dioxide is slowly but constantly being replenished elsewhere on Earth by emissions from volcanoes on land and at mid-ocean ridges. But today humans—by retrieving and burning hundreds of millions of years’ worth of this carbon buried by geology—contribute 100 times more carbon to the atmosphere every year than volcanoes.
The earth has a brilliant way of dealing with too much CO2. When carbon dioxide in the atmosphere goes way, way up from increased volcanic activity (or from, say, coal-fired power plants), the planet warms up from the greenhouse effect. But the catch is that in this warmer, stormier, high-CO2 world, CO2 is also drawn back down into the earth even faster. This is because the more acidic rain, warmer temperatures, and increased rainfall created by excess CO2 all work in concert to intensify rock weathering. This causes the planet to cool off more quickly when it gets too warm, by drawing down more CO2,, which ends up as limestone in the ocean. When the planet finally cools, the processes of rock weathering slow down as well, the drawdown of CO2 relents, and the planet returns to an equilibrium.
This is the carbonate-silicate cycle. It’s our planet’s improbably effective way of regulating the climate. It’s also known as “Earth’s thermostat.” But sometimes the thermostat breaks.”
The most extensive mass extinction ever, which happened in the end of Permian, about 252 million years ago, was caused by the Siberian Trap eruptions. But it wasn’t the floods of lava that caused the mass extinction but the enormous volume of volcanic gases they released, and the most important of these is carbon dioxide, which can short-circuit the global climate and dramatically affect the ocean chemistry.
And not only that, the magma from the Siberian Traps intruded into the Tunguska sedimentary basin, who were filled with more than 12 kilometers thick carbonates, shales, coals from ancient forests, and enormous layers of salt from dried-up seas. When the magma hit the salt layers, it occasionally got stuck and seeped sideways in giant magmatic sills that ignited the ancient coal, oil, and gas buried under the Permian landscape.
“These spectacular explosions would have supercharged the atmosphere with carbon dioxide and methane, an even more powerful greenhouse gas than carbon dioxide that turns into carbon dioxide when it degrades. It’s this fossil fuel combustion, Svensen [a geologist from the University of Oslo] said, that accounts for the huge crazy swings in carbon isotopes at the extinction—and that even accounts for the extinction itself.
The cause, then, of the End-Permian mass extinction and our own looming modern catastrophe might have been one and the same. The Siberian Traps intruded through, and cooked, huge stores of coal, oil, and gas that had built up over hundreds of millions of years during the Paleozoic. The magma had no economic motive, but the effect was broadly familiar: it burned through huge reserves of fossil fuel in a few thousand years as surely as fossil fuels ignited in pistons and in power plants.”
50 million years after this extensive extinction, another mass extinction event happened, and it too was a result of a very dramatic increase in carbon dioxide resulted from volcanic eruptions.
But in addition to volcanism, a high potential element [d7] played a key role in this extinction episode.
“The global warming of the End-Triassic destabilized huge stores of frozen methane at the bottom of the ocean that came bubbling to the surface. Methane is an extremely potent greenhouse gas, and when it degrades in the atmosphere, it becomes carbon dioxide. A catastrophic release of methane from the bottom of the ocean would have compounded what was already a climate catastrophe in the Triassic. Today similar reserves of frozen methane lurk in the cold dark corners of the ocean. University of Chicago geophysicist David Archer has written about the destructive potential of these deep-sea stores of carbon: If just 10% of the methane in hydrates were to reach the atmosphere within a few years it would be the equivalent of increasing the CO2 concentration of the atmosphere by a factor of 10, an unimaginable climate shock. The methane hydrate reservoir has the potential to warm Earth’s climate to [extreme] hothouse conditions, within just a few years. The potential for devastation posed by the methane hydrate reservoir therefore seems comparable to the destructive potential from nuclear winter or from a comet or asteroid impact.”
The need to refresh and remind the causes of the past events is to emphasis the linkage between them and what many see as the sixth mass extinction event (and others still consider as “what is about to be the sixth mass extinction”).
“It’s pretty clear that times of high carbon dioxide—and especially times when carbon dioxide levels rapidly rose—coincided with the mass extinctions,” writes University of Washington paleontologist and End-Permian mass extinction expert Peter Ward “Here is the driver of extinction.”
These events are of course very rare, but our world undergoes changes not seen for tens of millions, or even hundreds of millions of years.
Supervolcanoes aren’t the only way to get lots of carbon buried in the rocks out into the atmosphere in a hurry. Humanity is doing it for the last 200 years, digging up hundreds of millions of years of carbon buried by ancient life, and igniting it all at once at the surface, supercharging the atmosphere with carbon like an artificial supervolcano.
Since the industrial revolution, humans are earth’s volcanoes. And the rate of CO2 emissions by humans is 10 times the rate of the greatest extinction ever caused by volcanoes eruptions.
There were times when the atmosphere was richer in CO2, but when climate change or ocean chemistry changes have been sudden, the result was dramatic.
“The five worst episodes in earth history have all been associated with violent changes to the planet’s carbon cycle. Over time, this fundamental element moves back and forth between the reservoirs of biology and geology: volcanic carbon dioxide in the air is captured by carbon-based life in the sea, which dies and becomes carbonate limestone on the seafloor. When that limestone is thrust down into the earth, it’s cooked and the carbon dioxide is spit out by volcanoes into the air once more. And on and on. This is why it’s a cycle. But events like sudden, extraordinarily huge injections of carbon dioxide into the atmosphere and oceans can short-circuit this chemistry of life.”
The importance and relevancy of this book lays in the basis of the analogy. All the mass extinction episode were caused by dramatic changes to the climate and the ocean, driven by the forces of geology. Back then it was mostly volcanic eruptions but today humans emit massive amounts of CO2 to atmosphere at a very fast pace.
The book’s purpose is to act as another wake up call for humanity in the face of global warming, which can reach according to the author to another mass extinction episode which will include humans themselves. Of course human extinction is not an alarm but a solution. So the real moral of the story of the 5 mass extinction episodes is that they all have the same cause – a rapid change in the CO2 levels in the atmosphere. That is a very consolatory fact given that mass extinction episodes are not only a product of celestial elements which are almost beyond our control, such as comets and asteroids or gamma ray radiation, but of a terrestrial element. One that is already happening on a mass scale.
This book is indeed a potential wake up call. A potential wake up call for activists who currently passively long for a “doomsday” event, as if it is the only option for human extinction, instead of looking for ways to actively bring it. Ways such as combined efforts on a biological and climatological level, as well as other potential leads.
Our goal is to end the end of the world heart wish, and start the end of the world mission.