Guest post: Tom Phillips ranks some apocalypses by how likely they are to kill you
Your cheery guide to the end of the world. Happy Saturday, everybody!
My sometime co-author has written a book without me! To be fair, he’s done it before. So have I. All the same, there’s no loyalty these days
Anyway, his latest book, A Brief History of the End of the F**king World, was published on Thursday and has had excellent write ups in the Telegraph and New Scientist. To convince you lot to buy a copy, I invited Tom to give us a brief rundown of some of the things that might – but almost certainly won’t – kill us all.
(Also, seriously, buy the book, you’ll love it.)
Asteroids
Let’s start with one that’s been on our minds lately – thanks to the brief panic about a lump of rock of indeterminate size named 2024 YR4, which recently spent a few weeks as the single most concerning object in the solar system (possibly excepting Elon Musk).
The fun (???) thing about 2024 YR4 was that the uncertainty around its size – initially estimated at between 40m and 100m wide – meant that it covered a full range between “basically survivable if you get in a building and don’t stand near the windows” and “most of your city has been obliterated”. What’s perhaps most concerning is that this puts it right at the lowest end of the Space Rocks Worth Bothering About stakes. The really bad bits of the Torino scale (the apocalyptic space rock classification system that Jonn wrote about the other week) are reserved for much larger monsters.
Like, for example, the six mile-wide one that hit off Mexico’s Yucatán coast 66 million years ago and ended our planet’s dinosaur phase. This is the reason asteroids occupy such a prominent place in the doomsday canon: because probably the single most apocalyptic day in the history of the planet was the fault of one. The real killer here wasn’t the impact itself, which merely wiped out most living things in the Americas1; it was the dust and debris from the impact, combined with the soot from global wildfires, which stuck around in the atmosphere and plunged the planet into years of dark, freezing winter. (Note: this is a theme that will come up again.)
But despair not: such impacts are super rare, and moreover we’ve got really good at spotting them. (Even the small ones, like 2024 YR4.) What’s more, if we do spot our doom rock in good time, we might actually be able to do something about it. The other year NASA drove a small spacecraft into a passing asteroid to see if they could knock it off course, with frankly spectacular success. We might not even need to send Ben Affleck up there with a nuclear weapon, which feels like good news all round.
Apocalypse rating: 4 mushroom clouds out of 5.
Comets
Like asteroids, except often bigger, faster, and with the added complication that they sometimes come from unexpected directions – making them tricky to spot, and harder to deflect. A surprise strike from a really big one could wipe out virtually all life on Earth.
The good news is that such impacts are really, really rare, with frequencies counted in the tens of millions of years. The bad news is that we might not have had one in… tens of millions of years. Oh.
Apocalypse rating: 5 mushroom clouds out of 5.
Supervolcano
The concern with a supervolcano – like, say, the Yellowstone caldera going boom, which it probably will do, some day – is less the immediate volcano of it all, but once again the long, planet-wide winter that might follow it as dust and ash blocks out the sun. On the regular volcano scale, this is what caused the famous “Year Without A Summer” that led to Byron and pals getting louche and inventing horror fiction. At the supervolcano level, the fear is that it could be an extinction-level event.
The reason to be, maybe, a bit less concerned by this is the Toba eruption 74,000 years ago. This was the most powerful supervolcano eruption in the last 2.5million years, and for a long time people thought it had brought early humans to the brink of oblivion. More recent studies, however, have suggested that our ancestors actually seem to have coped with it… pretty well, actually. Perhaps we’re more volcano-proof as a species than we feared?
Apocalypse rating: a frankly pathetic 1 mushroom clouds out of 5.
AI
Look, unless we’re faced with a very niche apocalyptic scenario that involves knowing how many fingers humans normally have, then I am not too concerned that recent advances in AI have brought us meaningfully closer to doomsday.
Apocalypse rating: 1 mushroom clouds out of 5.
Nuclear War
Let us agree that the awful effects of even a single nuclear weapon are bad enough that we should never, ever use one again. Not even a little one. But from a purely apocalyptic perspective, once again the greatest threat comes less from the immediate destruction – even incomplete nuclear disarmament has been a very good thing – than from the possibility that multitude of nuclear firestorms shoot enough soot into the atmosphere to create a nuclear winter. This would be the true civilisation-destroyer, the devastation from it far outstripping the effects of even an all-out nuclear war.
The unsettling thing is that we don’t really know if it would happen. The difference between apocalypse and not-quite-apocalypse could come down to the exact optical qualities of the soot produced, or even the season we decide to have our war in. And we’ve no real way of knowing for sure; it’s not like we can experimentally nuke a city to see what kind of soot it makes. (NO WE CAN’T, IF YOU’RE READING THIS MR. PRESIDENT.)
Apocalypse rating: 4 mushroom clouds out of 5.
Pandemic
Look, the unhappy truth is that the recent, uh, unpleasantness was very much an entry-level pandemic. It could have been a lot worse.
The bad news is that it’s far from certain that that’s us done with pandemics for the foreseeable future. Based on historical trends, we had about a one-in-three chance of a Covid-level pandemic happening in any of our lifetimes, so we got a bit unlucky – but not absurdly unlucky. Unfortunately, those odds are probably changing for the worse. Both climate change and the expansion of human settlement ever-further into wild animals’ territory are making zoonotic spillovers ever more likely. The odds are uncomfortably short that Covid won’t be the only pandemic many of us have to endure.
But for all the apocalyptic vibes of March 2020 and its empty streets, could a pandemic be truly apocalyptic, in a Last of Us or Station Eleven kind of way? On the one hand, there’s a very good argument that infectious disease didn’t manage to wipe out humanity for the entire time before we developed germ theory, and so it probably won’t now that we have. On the other hand, it is not clear that this argument has fully reckoned with the concerted efforts of Robert F. Kennedy Jr., so it’s honestly kind of a toss-up.
Apocalypse rating: 3 mushroom clouds out of 5.
Climate Change
On a global scale, climate change will not be the apocalypse; on its own, it will not wipe us out, or render our civilisations a thing of the past. Rather, it might be better to think of it as a rolling series of small, increasingly unpredictable local apocalypses. Your house, your town, your way of life suddenly rendered non-viable; a steadily increasing and unnecessary toll of deaths from once-in-a-century disasters that gradually happen more and more often.
It is, fundamentally, a challenge to our deeply ingrained sense that things only matter if they’re going Full Apocalypse. This is a deeply tempting human impulse, and it will do you no good when a little mini-apocalypse shows up in your neighbourhood. We should not need things to be doomsday to recognise that they are bad.
Apocalypse rating: 3 mushroom clouds out of 5.
Nearby Supernova
That was a bit of a downer, so let’s cheer ourselves up. If a supernova went boom in our neighbourhood, that would be… awful. As in, “the energy of a hundred quintillion suns all at once” bad, an event that could at minimum leave our nice protective atmosphere in tatters.
As such (this is the cheery bit) you’ll be delighted to know that this isn’t going to happen to us any time soon – stars don’t just go supernova at the drop of a hat, and there are no candidates for imminent supernovadom in our neck of the cosmic woods. Betelgeuse, which is probably the closest thing we have to something worth worrying about, is unlikely to go supernova for another 100,000 years, and even then is probably too far away for it to have any significant effect on us.
Apocalypse rating: 1 mushroom clouds out of 5.
Not enough CO2
OK, so don’t take this the wrong way, but ultimately what will likely doom life – or at least life as we know it – on Earth is… a lack of CO2 in our atmosphere. As the Sun gradually gets hotter, geological processes that trap CO2 in the Earth’s crust will ramp up, to the point where there won’t be enough to sustain photosynthesis. At that point, it’s goodbye plants, goodbye ecosystem, goodbye oxygen.
The good news is that this won’t happen for another billion years, so it’s not of especially pressing concern to us right now. (Also there’s probably plenty of time for new types of life to evolve that aren’t as CO2 dependent?) And before you ask: no, making lots more CO2 now really won’t help very much.
Apocalypse rating: 2 mushroom clouds out of 5.
Sun swallows Earth
As our star nears the end of its life, it will become a red giant, swelling to a hundred times its current size. Mercury and Venus will be consumed, and Earth might be too. Even if we’re not technically swallowed up we’ll be scorched into oblivion. This probably isn’t something to get too worried about, however, because it’s not going to happen for about five or six billion years.
Apocalypse rating: 3 mushroom clouds out of 5.
False Vacuum Decay
This is a really fun one, by which I naturally mean “profoundly haunting at an existential level”. There exists the possibility that our universe is, fundamentally, not quite as stable as we might have hoped. At the quantum level it might exist in a state known as a “false vacuum” – a state from which it might abruptly collapse down to the lower energy state of the true vacuum.
The result of this would be a bubble of alternative physics that would expand outwards at the speed of light. It would be a new universe, swallowing the old one; we would never know it was coming, and would instead simply wink out of existence in an instant.
It was this scenario that prompted the physicists Sidney Coleman and Frank De Luccia to write one of the most gloriously morbid passages in the history of science. Describing it as “the ultimate ecological catastrophe”, they add that “after vacuum decay, not only is life as we know it impossible, so is chemistry as we know it. However, one could always draw stoic comfort from the possibility that perhaps in the course of time the new vacuum would sustain, if not life as we know it, at least some structures capable of knowing joy. This possibility has now been eliminated.”
Working out whether this is a thing that will actually happen rests on the inconceivably precise measurement of obscure quantum properties. As things currently stand, this is another one of those bad news, good news situations: yes, it probably will happen, but we’re probably safe for the next few vigintillion years or so. (I’ll let you google how many zeros vigintillion has. It’s an awful lot.)
Apocalypse rating: 2 mushroom clouds out of 5.
All – or at least some – of the above
Call it an onmishambles, call it a polycrisis, maybe call it a polyshambles or an omnicrisis; maybe just call it “The Jackpot”, as William Gibson did. Perhaps the greatest apocalyptic fear is not any individual catastrophe, but a bunch of them one after the other. It’s not clear that anything short of the biggest, most unexpected comet strike could actually take us out as a species – humanity, as we’ve shown, is a survival machine. But the cumulative effects of many of them in close succession…?
There’s precedent here. The Late Bronze Age Collapse in the Mediterranean is probably the most dramatic and widespread civilisational collapse in known history, with multiple civilisations either falling apart or becoming badly reduced in the space of a few decades. The causes have been long debated (the arrival of the mysterious and terrifying “Sea Peoples” makes it all extra haunting), but the most recent scholarship suggests that there was no single cause - a bout of severe climate change caused a region-wide megadrought, which destabilised polities enough that a domino effect of smaller crises was enough to eventually bring them down. The terrifying Sea Peoples were probably not the implacable raiders of legend, but climate refugees who were victims of the same crises overload.
In short: if we spend all of our time worrying about the apocalypse, we might miss all the smaller crises that will add up to the big one.
Apocalypse rating: 6 mushroom clouds out of 5.
Tom Phillips’ A Brief History of the End of the F*cking World is published by Wildfire now. You can buy a copy here, or frankly wherever you get your books. You absolutely should, too. While you still can.
Phew.