How well would modern society handle the dinosaur killing meteor if it happened today?

Factual Questions
261

Been a lot of comments above that seem to blur the various timescales.

Folks near the point of impact will die in seconds or minutes. The antipodes will be bombarded 45 minutes later. The tsunamis will take minutes to hours to slosh across the ocean basins. Likewise major earthquakes as the planet rattles. The firestorms will take an hour to get really going after the bombardment arrives wherever they are. And may take multiple hours or days after that to grow and consume anything and anyone flammable that’s nearby.

Civilization will continue for a few hours after impact in the areas not directly bombarded, then begin falling apart as panic and fatalism take hold, aided and abetted by the usual trolls and CTs. Until the internet quits and the armed panicky bands take over.

Within 2 weeks substantially everyone on earth is starving. The exception being the poor subsistence farmers who have the good fortune to be well inland and orthogonal to the impact/antipodal points. OTOH, those folks crops will fail and soon they too will be starving.

If the climate recovers quickly, (e.g. 5 years to viable crops) it’ll be the year 1200 AD all over again for the many isolated bands of survivors. If the climate takes a century to recover and is wildly different, make that 5000BC for the few isolated bands of survivors.

Any thought that modern tech survives is IMO crazy.

262

So what you’re saying is that if I really want to secure my supply of toilet paper, I only have about 2 hours, not the entire afternoon, to make it to the supermarket. I’ll have to get to the carwash afterwards. I can predict that this will be annoying.

263

Just a point of reference: This was visible from Montreal, and most places in Vermont. Interesting to think what a scaled-up version could do…

A meteor streaked through the night sky over Vermont on Sunday (March 7), creating a spectacular light show and causing Earth-shaking booms as it burned through the atmosphere.

The meteor’s explosive passage through the atmosphere released the equivalent of 440 pounds (200 kilograms) of TNT, suggesting that the meteor was likely 10 pounds (4.5 kg) and 6 inches (15 centimeters) in diameter, according to [NASA Meteor Watch]

264

The assumption here is that we’ll get hit by something in a regular orbit, not something that’s only just been perturbated.

Also, there’s a whole class of asteroids that are mostly only sunside of us. No, I don’t think there’s a 15km one hiding there. But there are some that could seriously spoil our civilizational fun.

265

In order to make that much of a change in their orbit, they’d have to make a rather close pass to a planet. That does happen, but it’s not super common. Although we’re tracking one rock that every once in a while passes somewhat close to Earth: 99942 Apophis. It just recently made a pass, although not an especially close one. Eventually it’s either going to hit the Earth or be perturbed into an orbit that does not make Earth passes.

Yes. I looked through the first twenty or so on the Earth-crossing minor planets list at Wikipedia. Most were in the 1 to 5 km range, a few were or may be in the 5-10 km range. The largest was about 8 km. Any of those would make it a pretty bad day if they hit the Earth.

266

Oh, yes, I should emphasise that I don’t think the chances of any dino-killer asteroid are super-high, and the chances of one we completely don’t see coming are even lower. But Chronos’ mention of Iceland that I initially replied to was in the context of them being primed to survive regardless of specific preparation, so that was the scenario I was responding to.

267

The point with earth-crossing minor planets, or any asteroid that can come close to a planet, is that such an encounter will change its orbit - slightly, depending on how close. The catch is this may have a cumulative effect - it may make it easier/closer for the next encounter, etc. Something like that we should see coming a long time away and be ready to create a diversion. It’s the ones that come out of deep space we may have no warning of, either comets with many-millennia-long orbits, or interstellar passers-by.

I’m going to imagine that most Icelanders live close to the ocean, and the first thing a dinosaur killer would produce would be massive tidal waves sloshing well over the coastal plains of any land mass. See how much damage the 2006 wave or Fukushima did with only a one or two dozen feet of water rise. Iceland is also notorious for geological activity, which I imagine too would be triggered to new heights by a severe shaking of the earth’s crust. Even a big lake shoreline could be risky.

The “nuclear” winter would probably only last a few years, so odds are “only” a few years’ supply of food would be needed to survive. It does not need to be underground, since there’s no radiation issues; just a decently insulated building. More likely, a remote site would be preferable, because for the first while you’d have to fight off the local hordes trying to get in and get food. A burrow hide-away would simply leave the inhabitants wide open to those enterprising enough to use heavy machinery or explosives to gain entry. Better would be a small tower (if it survives the impact shaking) because you’d have the high ground to fire on anyone trying to breach the perimeter.

Mind you, even two or three years of winter could totally devastate the ecology, but I’m guessing enough seeds would survive to kickstart the environment. Just - how long can you wait for the forests and swamps to rejuvenate, and which pieces will be missing?

268

Having found 90% of the large potential impactors still leaves 10% that we haven’t found. And that’s a number much larger than I’m comfortable with.

269

Okay. Indeed his post #96 did indeed assert that “even if another dino-killer struck right now, with no advance warning, they’d probably survive.” No claim there though that, without any warning they’d survive with fully modern society intact. Iceland, brought up again in #163 was not with any claim of no advance warning - more just as a way to point out that the effects of an impact would be variable on different parts of the world. Everywhere would have an impact winter of some several years. But not every volcano would erupt at that moment and many of those that did might be more slow release of CO2 and not explosive. Not every coast would experience a tsunami.

Humanity is widely scattered.

Unlike the dinosaurs we can be prepared such that a pocket or two that survive the days to weeks following the impact (firestorms, tsunamis, etc.) has the food stores, energy generation, so on, to survive the several years of impact winter. IF they do so with critical knowledge preserved, as well?

We can I think easily imagine 90% of humans dying at impact or within a day or two after. 90% of the remainder not being in a pocket that is able to survive impact winter. 90% of those who do isolated but able to survive somehow in a primitive manner. But if even 0.1% of humanity’s nearly 8 billion happen to be in a few locations not consumed by the immediate effects of impact, have some advance warning, are able to have enough food stored or able to be produced with energy generation preserved, have a plan in place for how to emerge after impact winter with knowledge preserved? Heck let’s use even 0.01%. 800,000 people mostly clustered in the regions that did not get destroyed? The civilization that emerged would not be modern civilization we have, but it would not be Stone Age humanity either.

Of course the efforts to get to over 90% of smaller, but still potentially very harmful, ones, will likely identify more of the over 1 km ones too.

That said … if you have a choice between prioritizing an extra unit of money to better identification of these impact threats, or to addressing the in progress existential threat that is climate change, which would you choose? (I know it is not either/or completely, but it may be that there is a point where further identification starts to cost much more per threat identified.)

270

That’s a lot of ifs. The biggest one being the first. Most of humanity lives right by the coasts, and/or in geologically unstable areas. I think only 90% is unjustified optimism.

I think if more than 8,000 humans are still alive a year after the impact, that would be a literal miracle and proof of God.

271

0.1% of 8,000,000,000 is 8,000,000. I think the odds that 8,000 survive is pretty good if general devastation is random and erratic, rather than universal. I presume inland cities on stable tectonics are not too much of a risk if far enough away - Moscow, Columbus OH, Berlin, maybe even Delhi. The question is how big any impact would be felt as a local event on the Richter scale for such cities, as they are not constructed for earthquake resistance. Also, if the complete atmosphere goes into over-heat mode, and for how long? People indoors in concrete buildings, in the basement, might survive a few hours of that. The real problem becomes surviving once the winter sets in. The larger the population that survives in a location, the less likely there’s enough food for all. There will be however, plenty of frozen meat, if one is not too picky about what (or whom) they eat.

So if the buildings survive, don’t get washed away, don’t catch fire - then it’s all about the couple of years of food supply.

272

Lots of cities are on the coast, but they’re not all on the coast of the same ocean. If an asteroid hits in the middle of the Pacific, that’s going to produce an impressive tsunami, but not so impressive that it’ll drown New York.

And yeah, no matter where it hits, our current society isn’t going to survive it. The society of the survivors will be radically different. We won’t be literally blasted back to the stone age, but it won’t be all sunshine and roses, either.

273

There’s the difference of opinion.

I’m of the “universal devastation” opinion, with patches of “actual hellscape” at lots of tectonically-suitable locales. It is literally going to rain molten glass over most of the planet for days. The ozone layer won’t exist anymore, likely for years. Acid rain will be the only kind of rain. And then - impact winter. “Indoors in a concrete building” just means you don’t die in the first few hours.

274

…unless the impact has a knock-on effect with its shear seismicity, like setting off the La Palma landslide.

275

Ah, Apophis, nice one. I cannot but marvel at your and some other poster’s unwaivering optimism. I recall you had a similar attitude when we discussed Covid almost a year ago - and so did I, my guesses concerning the number of deaths at the end of the year were much higher than yours. Must be a personality trait. So I am not going to convince you that the impact would be much worse than you hope, just as you are not going to convince me that surviving as a species is almost a given. I wrote a book about 15 years ago, unfortunately in German, so I can not show it to you in any meaningful way (or do you understand German? Are you ready to go through a machine translator like Deepl.com?), the subject was airships (you mentioned them some posts ago, I loved it), extinction, Apophis (no, really! Chapter 47 and others), frogs, the seed vault in Svalbard you mentioned above (chapter 93), madness and pets (Chapter 64 and 65, and many more, it is a long verbose book - probably also a character trait.)If you care to have a look, it can be read for free here. I just mention that to show that we have similar interests, only very different approaches, and that I take you seriously.

Now for the things I see differently concerning our asteroid. I will try to be systematic.

So a meteorite is coming towards planet Earth. A big one, Chicxulub-event size, that is the premise in the OP, though we don’t really know how big that one was, so we may play with the numbers. There are two possibilities: we see it well in advance (years) – or it takes us by surprise (months or days). I’ll dismiss the second possibility because the OP asked about what could we do if, and if we see it too late there is nothing we can do.

So we see it looong before it hits the fan. Now we must either break it up or deflect it. (Spoiler: we can do neither. It sucks, but physics is cruel and mercyless. Please bear with me and just keep on reading). In case we don’t manage we will try to prepare as good as possible for the event and brace for impact.

First we try to deflect it. That is sensible, if it does not hit us at all, the problem is solved. Now let’s move an impactor between 6.82×10^15 kg and 1.28×10^16 kg (Wikipedia dixit, under Chicxulub impactor ). Lasers have been sugested: if you fire them from the ground the atmosphere scatters the beam (and the beam scatters the atmosphere and burns a hole in it), if you fire them from space there is no way to cool the machine if it is to be powerful enough.

I postulate that we have to move the biest 10,000 km (10^7 m) laterally, that is: 6,000 km Earth radius and a safety margin of 4,000 km. That is a small safety margin, but could be enough. What force do we have to apply to the body? That depends on how much time we have. Now I will be the optimist one: say we have 10 years time to apply a constant force and the means to do so (I will come back to the means in a moment). A year is the same as 31,557,000 seconds, ten years 315,570,000 s, that is about 3,2×10^8 s. What have we got? Something between (6.82×10^15 kg and 1.28×10^16 kg) times 10^7 m divided twice by 3,2×10^8 s, which is about between 666,000 and 1,250,000 kg m/s² (or Newton). Well, that is not that much! Only this force has to be applied every second, ten years long. Do you agree with this calculation? We have to exert a force of 1,000 kN on the body every second for ten years. How could we do this?

One option is with lasers, the other by detonating A- or H-bombs close to the body (which I will call Helen from now on, for reasons. Only known to my first wife and me). Let’s try:

Lasers: light does not exert a signficant force on Helen by itself, the idea is to melt and then boil away the mass necessary. If possible, in the right direction with the right velocity. 1,000 kN is the force of a mass of one metric ton ejected with a speed of 1 m/s. Every second. If Helen is made of ice (quite plausible, according to my experience) melting and blasting that material away heating one ton of ice to 0°C (actual temp out there: around -100°C, we are still beyond Jupiter if Helen needs ten years to reach us), and then some more to give the ton of water some impulse. That is at least 100,000 kCal/s to rise the temperature and 80,000 to melt it. To this we must add the laserlight reflected, that will depend on the albedo of Helen. That can be quite high for bodies made of ice. In fact, I would rather heat Helen up to boiling point (100,000 kCal more per second) and then boil her (540,000 kCal, the latent heat. Quite a lot). Am I right?

Now if Helen is made of iron, we will never be able to melt and boil to eject one ton every second, the numbers would be even higher (althoug the latent heat and the specific heat factor of iron is much lower, the temperature to reach is much higher. Melting point of iron: 1,535°C, boiling point 2,861°C. Plus latent heat. One ton every second! And I bet this darn Helen rotates, which makes heating her up as desired even more difficult. I am afraid we can forget this.

Atomic or hydrogen bombs? To eject one ton of material every second on average (the bombs will work on pulses: one explosion, one pulse, assume we get one every day to the very precise location and blast it, so that it manages to eject 1 ton times 60 times 60 times 24 = 86,400 tons in the right direction with the right speed – no mean feat) we would have to send almost 4,000 bombs to the right place, which in itself will consume some of the 10 years I optimistically assumed. Do we have 4,000 bombs and rockets for them? I doubt it.

So we will have to break Helen up (I’m starting to like this). I already calculated (see post above) that if we smash Helen to tiny pieces, so that all the energy is transfered to the atmosphere during entry (no pieces reach the ground) this would heat up the atmosphere by around 20°C, or 40°C if this happened only on one side. You objected to this second scenario because the Earth turns. Granted. But 20°C is catastrophic too. At least we would not need bunkers to hide, only refrigerators. And the energy to keep them going. No atomic energy is possible! Cite, cite.
If we only manage to break Helen up to pieces of around 80x80x80m we would have about 6,000,000 of them, which is 2,000x3,000, a number I have chosen because it probably is about the resolution of your computer screen if you have a good one. Take a world map, make it fit within your screen and imagine one meteor of that size falling on every single pixel. Than does not look like a good idea either.

Perhaps the best thing is to leave Helen intact and hope that when it falls the story of the dinosaurs repeats itself. Some places might be more protected, lucky or whatever and something would survive there. My guess is that if some of the energy is not turned into heat but used to make a crater, a tsunami, to heat the interior of the Earth the effects might be lighter.

But then humanity must brace for impact. And here is where I fundamentally disagree with your approach: we have left out psychology in our considerations. All of humanity must work together to save a few. Would the ones not lucky, or mighty, or ruthless enough to be saved actively work, and work well, for the benefit of the others? Would you work carefully and honestly to save me, for instance? And save the kind of people who would elbow their way into the saving list too? People like, say, Jeff Bezos and Mark Zuckerberg and the crown prince of Saudi Arabia and Kim Kardashian? (and I haven’t listed the worst ones!) I for one can tell you: I would sabotage the whole endeavor if forced to work for them. And how would they force me if I was going to die anyway?

I think this post is already too long, so I am not going to dwell into why atomic energy is not the solution, but an aditional problem, especially if the atomic installations are not shut down properly and result in 500 Chernobyls after the impact, and what will happen with all the big dams like Assuan (bye bye, Cairo) and the Three Gorges Dam and the Hoover dam when they are not mantained for years full of earthquakes and so on.

276

Actually, there won’t be any edible frozen meat.

The process of making commercial frozen meat cools it from living temp to frozen temp quickly, in an hour or two at very most, and usually much less than that. The natural effects of post-impact winter will cool the meat over a matter of weeks. Except in the polar regions where very little of the population lives.

There will be billions of frozen human corpses if the “winter” gets bad enough. But almost all will be long spoiled as food. The same depressing reality applies to all the former livestock too.

As Coleridge almost put it:

Food, food, everywhere, nor any bite to eat.

277

But at least we can agree on that! :grinning:

Herein lies the issue:

But this is not the IMHO forum.

The models available suggest that the large portions of the world was on fire but not all of it. Models have been cited that suggest great variability with higher latitudes being relatively less devastated. There was devastation globally but as I understand the current consensus while many died in the due to the immediate “fireball stage”, mass extinctions were more driven by the inability of most species to survive impact winter.

IOW many many species survived the “fireball stage” but the fewer, especially not the dinosaurs and flying reptiles, were able to survive the collapse of the food chain that was impact winter.

So for example

Adding it up … the firestorm stage would have been very bad. Killing those in the paths of the firestorms would be dead, and those in coastal cities would be at high risk with many killed by tsunamis. But again humanity is very widely distributed and just as many dinosaurs survived the immediate firestorm stage, it seems highly likely that some (possibly very small) fraction of humans would.

With some even short ability to prepare then could any of those humans then survive impact winter with knowledge and know-how of technology intact able to rebuild some new version of civilization from small numbers, literally out of what would be a vast junkyard, and what was left in preparation?

That is the hallmark of our species, the ability to use culture and accumulated knowledge to prepare, to plan, and to adapt to rapidly changing conditions and novel problems.

As to this:

One suspects that the ability to precisely model exactly where the asteroid would hit would not be so perfect. Spreading out knowledge and the moving of populations to statistically less probable sites is each person buying a lottery ticket. Human nature is that we over-estimate the chance that we are in possession of the winning ticket. This from an interview with someone before D-Day told that two of three of them will not return alive: “I looked to my right, and looked to my left and thought - poor bastards.”

278

We can also agree that the truth in our forecast on Covid-19 deaths lies in between our respective estimates (but closer to mine :stuck_out_tongue_winking_eye: - by order of magnitude at least. OK, closer to yours if we count the absolute numbers, but that is statistically flawed). So here in this debate, between my postulated total destruction and anhilation of the human race and your more optimistic scenario where some survive we might reach a consensus where some zombies survive :smirk:.

Oh yes it would: the time of impact can be calculated by an amateur astronomer, the direction from where it comes is known, so we would know pretty well the longitude of the impact. The latitude would be know some months in advance at the latest. The lies and the obfuscation and the conspiracy theories are another matter altogether, but that calculation would be feasible.
One thing is sure: many people living near coasts would want to move land inward: Florida, New York, Shanghai, Kolkatta, Lagos, Lissabon, Barcelona, Hamburg, Tokyo, Cairo… most of humanity lives by the shore. When I think of the frenzy a couple of ten thousand poor unarmed Hondurans caused in one of the richest countries on Earth, or the political earthquake bordering on panic some 100,000 refugees have caused in Europe, I don’t believe this process would be smooth and peaceful.
But if we must choose an island for the survivors I would like to table the motion that we swap Island for Hawaii. Still I believe that an island is a very bad idea: Tibet would be better. Or Bolivia.

I am not sure I understand the differences between General Questions, Great Debates, MPSIMS and IMHO, but at least I think I am beginning to understand the Pit. But I am glad we keep this civilized :smiley:

279

Cite, please. By “dinosaurs”, I assume you mean “non-avian dinosaurs”, though. But I mean a cite for the “many”

It’s a nice bumper sticker text, but no. The hallmark of our species is exactly the opposite, or there wouldn’t be 8 billion of us, and we wouldn’t currently be in the middle of another extinction we caused, and climate change would not be a thing. We do the very opposite of prepare and plan.

280

Well I might have a penchant for optimism, could be. That said I take some comfort in the good company I share being off in early day COVID-19 WAGs (and stand by my early beliefs emphasis that everyone was making WAGs with some professing more confidence than was warranted, not at least acknowledging that the assumptions they used should have been held very very tentatively). As for my own psychology in this thread, I suspect it is more my ornery side! Probably it is a bit knee jerk for me to respond to excessively confident assertions made that humanity would be extinct with the evidence against such claims.

Personally I would want to set up shop inland in Norway. IMHO.

“Most” is slightly hyperbolic. It’s a factoid that been documented as coastal communities are already at grave risk from the *actually" imminent existential crisis - climate change. 40% live within 100 km of the coast. That’s a lot and a big deal for what we are likely to see within the next century.

(Climate refugees are possibly going to be a test case for how we’d deal with a predicted impact. Yeah I suspect there will be nationalism and border skirmishes.)

Would tsunami waves hit all coastlines? Would they be big enough at all locations to wipe out all who lived in those locations? Take worst case and it wipes out all who live within 100 km of any coast. That leaves survival of 60% of humanity past the initial several days to the question of how much everywhere the firestorm would be. 90% of the globe? 50%? Hellscape, go with 90% and you still have 6% of humanity inland and not burned up.

?
In the post the citation reads:

Bolded to help.