I know we really don't need anything else to worry about. World events have been depressing enough, and here in the United States we've got an election on Tuesday that is making me pop Xanax as if they were Skittles. But I ran across something in a book I'm reading that was absolutely jaw-dropping, and not in a good way, and I knew I would be seriously remiss in not writing about it here.
I mentioned a few days ago (in a post about some bizarre volcanoes in the East African Rift Zone) that I've been reading Tamsin Mather's wonderful book Adventures in Volcanoland: What Volcanoes Tell Us About the World and Ourselves. Mather's specialty is monitoring gas production from volcanoes, and using the composition of offgassed material to gather information about magma characteristics and the likelihood of eruptions. She's traveled all over the world collecting and analyzing samples, comparing hotspot volcanoes (like the ones in Hawaii) to rift volcanoes (like Ol Doinyo Lengai in Tanzania) to trench/subduction volcanoes (like Etna, Vesuvius, Krakatoa, Fujiyama, the Andes, and the North American Cascades). Her research puts her in position as one of the world's foremost and most knowledgeable experts on volcanic offgassing, and what it means for our understanding of what is going on inside the Earth's mantle.
In her book, she not only references currently-active volcanoes, but prehistoric eruptions -- and one of those she discusses is the astonishingly huge Siberian Traps.
This eruption, of a type known as a large igneous province or flood basalt, happened 252 million years ago, at the end of the Permian Period. Flood basalt eruptions occur when something rifts the crust of the Earth and deep-source, extremely hot basaltic (low silica content) lava flows out. This lava is incredibly fluid, and fills up valleys like water fills a bowl. In the case of Siberia, it was a quantity that beggars belief; current estimates stand at around four million cubic kilometers of lava. The disaster this caused was amplified by the fact that prior to the eruption, the Earth had had a long period of warm, wet climates pretty much worldwide, facilitating the growth of widespread swamps and rainforests. The age when this occurred is called the Carboniferous Period, so named because all that dead compressed plant matter locked up gigantic quantities of atmospheric carbon, forming enormous seams of coal.
When the Siberian Traps erupted, the lava ripped its way through those massive coal deposits, and the carbon they contained was suddenly returned to the atmosphere as carbon dioxide. Mather writes:
Estimates of total carbon dioxide emissions over the million-year-scale lifetimes of these basaltic floods are in the region of tens to hundreds of trillion tonnes... Estimates of varying emission rates over the very long lifetimes of these provinces are harder to make than the totals, but one recent study put the maximum emission rate during the Siberian Traps at around eighteen billion tonnes per year.
The result was widespread disruption of the climate, global marine anoxia, and the largest mass extinction ever -- the Permian-Triassic Extinction, which wiped out on the order of ninety percent of life on Earth.
The kicker comes in the very next paragraph, when Mather tells us that the rate of carbon dioxide production from the most massively devastating volcanic eruption on record, the rock from which covers an area of seven million square kilometers, is half the rate our current fossil fuel use is currently churning out carbon dioxide.
I don't exaggerate when I say I had to read that passage three times before I was convinced I'd understood her correctly.
I've all too frequently heard laypeople give a sneering chuckle at the climatologists, saying stuff like, "What a lot of bullshit. One volcanic eruption emits more carbon dioxide than all the cars on Earth do." They rarely cite a source, and when they do it's from something like the fossil-fuel-industry-funded Heartland Institute, but -- because this opinion is a great excuse for continuing to do stuff the same way we always have -- they almost never get challenged on it.
It's astonishing how easy it is to accept a false viewpoint when it gives you a comforting reason not to do anything inconvenient to your lifestyle.
But here's the straight scoop from Tamsin Mather, who (allow me to reiterate) is a volcanologist who specializes in analysis of volcanic offgassing:
Despite the wide error bars in our estimates of the global rate of volcanic carbon degassing, what we can know is that these natural emissions pale into insignificance compared to what humans produce. In 2019, human fossil-fuel burning released over 35 billion tonnes of carbon dioxide into our atmosphere. This is seventy times more than even our most generous current estimates of global magmatic carbon degassing. In 2022, the aviation industry alone emitted 800 million tonnes of carbon dioxide, eclipsing estimates of that from our planet's background tectonism before even considering other sectors of human industry. We cannot look to Earth's volcanism today to reassure ourselves that our rate of carbon emission might not be too much of a change in terms of our planet's natural cycles. Powerful as the forces of tectonics that daily drive the slow creep of plate movement and volcanic activity across the globe are, the human race has currently surpassed them in terms of its carbon dioxide flux to the atmosphere. It is apposite to reflect upon the level of responsibility that should appropriately come with the level of power attained by our species that, by this carbon metric, overwhelms all Earth's volcanoes.
Despite this, we have a candidate for president here in the United States -- I doubt I need to tell you which one -- who has stated he wants to discontinue investment in renewable energy and withdraw from the Paris Accords, and frequently says "Drill baby drill, and frack frack frack!" to cheering crowds.
Anyhow, I'm sorry to post alarming stuff, but perhaps now isn't such a bad time after all. We have the chance to make a difference not only by our actions and choices, but in the voting booth. It put me in mind of a conversation that occurs in my novel In the Midst of Lions, which seems a fitting way to end this post:
Mary Hansard's face registered near panic. "It's not just here. It’s everything we know. Soon it’ll all be gone, and if we don’t find a way out, us with it. We've got to do something, now.”
Soren glanced at Dr. Quaice. “Okay, this is scaring the shit out of me.”
Mary tightened her grip on Soren’s sleeve. “Good. Good. You should be scared. Scared people act.” She hitched a sob. “Complacent people die.”
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