What exactly would it take to wipe humanity off the face of the Earth?

[Kolby Jack]

We all speculate about what will happen when the apocalypse occurs, but we only care if a few survive. From Hollywood's perspective, just about ANYTHING short of the planet blowing up (and sometimes even that) will leave a few survivors. So I'm curious, how resilient is the human race? What catastrophe can we expect to survive and possibly even recover from? Humans are resilient enough to live in a wide variety of environments, but can we really live through pandemonium?

And let's omit the obvious: destruction of the Earth in the present day would of course mean the end of mankind, so forget about going THAT far.

 

[The Random Critic]

Resource scarcity, the lack of an alternative for said resource
overpopulation (could be considered as land scarcity, but meh)

All of these will cause multiple superpowers to fight, lack of compromise, world war 5, nukes, big booms everywhere
Then again, there will still be humanity left and war will once again never change

So I'll stick on other lifeforms, or a deadly biological pandemics. (that's not created by man but caused by nature. Like begin able to transfer AIDs without a needle)

 

[Soviet Heavy]

It's honestly hard to tell. As far as animals go, we are by far one of the most resilient species ever created. We're the last remaining member of our genus, and have been for millions of years. The only thing we know of capable of threatening us on a global scale is ourselves. We survived massive plagues, famine, war, illness, and hostile climates.

I do find it interesting in speculation how we are constantly coming up with new ways to kill ourselves off. I think it says something about our species that we have to resort to imagining one sided threats just to give something else an even chance against Humans. Until something DOES come and wipe us out, the only things that come close are in our imaginations. And we're probably already coming up with ways to survive those, too.

 

[Thaluikhain]

Currently, there isn't anything likely to wipe off humanity.

Nuclear warfare would "only" decimate the world's population and set civilisation back a few hundred years. Humanity would recover from that, given time. This would be of limited comfort to anyone at the time, of course.

...

On a related ish note, it always, always annoys me when some movie has a monster they call the ultimate predator because it has big teeth or whatever. Ask a smilodon or a megalania or a mammoth or a diprotodon how big teeth worked for it when humans turned up.

 

[Esotera]

Our sun going supernova is the only one that would kill 100% of humanity, or maybe an absolutely massive asteroid. It's pretty hard to kill 7 billion things that are distributed across a very wide area, and it's even harder to kill them in one go. So unless you can get multiple apocalypses, it's going to be pretty tricky, especially given that after the first one all the humans will actively be trying to survive.

 

[Queen Michael]

Me getting two more tons of uranium. I think I'll be able to aquire it by next Tuesday.

 

[MeChaNiZ3D]

I don't really know. Short (as per OP) of the Sun imploding/an alien race destroying us/a massive meteorite (anything that would just flat-out destroy the Earth), I don't know if anything could comprehensively kill everyone. Nuclear weapons come to mind, but if at least some people survive in bunkers or what not with the proper resources, they could probably live on an irradiated Earth. Climate change isn't even nearly good enough, we'd survive the worst case scenarios of that for sure (doing untold damage to the environment and losing lots of land in the process, but not even a threat to humanity as a species). I'm going to finish this post with sentient AI that can improve technology on their own and through some loophole in programming see us as a resource for something, but even then they'd be more likely to farm us than kill everyone off in one go.

 

[rutger5000]

Global warming + time = human extinction.

 

[Nickolai77]

You'll probably need an asteroid comparable in size if not bigger than the one which wiped out the dinosaurs to wipe out humanity, but that's not guranteed they'll be some human survivors. Nuclear warfare again, could wipe out most of the human species but will likely leave survivors in remote places. The only sure-fire way of wiping out humanity I can think of would be for the sun to nova or a blackhole to appear in our solar system.

 

[Sandernista]

Currently, there isn't anything likely to wipe off humanity.

Except the caldera in Yellowstone that could erupt any day. Instantly all of the US, Canada, and Mexico's populations would be killed, and following the century of no sun, the rest of the planet would soon follow.

If you've ever seen the movie "The Road", that's what it'd be like for the rest of humanity.

 

[Plasmadamage]

Currently, there isn't anything likely to wipe off humanity.

Except the caldera in Yellowstone that could erupt any day. Instantly all of the US, Canada, and Mexico's populations would be killed, and following the century of no sun, the rest of the planet would soon follow.

If you've ever seen the movie "The Road", that's what it'd be like for the rest of humanity.

Eh, I think you're underestimating how resilient we are. Sure, North America and Canada would end up under a kilometre of ash, but the oncoming volcanic winter will hardly kill us all. The biggest risk would be the destruction of agriculture around the world, but we have access to technology that can offset that now (hydroponics, sunlamps, GM)

I'm not denying that it will take a big chunk out of us, but I hardly think it will be the end. Remember, we survived the Toba supervolcano, and that was long before we had anything even approximating science.

 

[JoJo]

Me getting two more tons of uranium. I think I'll be able to aquire it by next Tuesday.

You better enrich that uranium quickly, my laser shark apocalypse is scheduled for Monday.

OT: Disaster followed by a slow decline is what I imagine could possibly take out all of humanity. As others have already said, even nuclear war and supervolcanoes would most likely leave a good chunk of us alive. The same with viruses, all have civilisation-destroying potential but humans tend to pull through nonetheless. If humanity was unlucky enough to be struck by something else after losing civilisation though... that could be the end. Hopefully we'll colonise space soon and become immune to all sorts of planetary disasters

Global warming + time = human extinction.

I doubt it. Even if we released all of the fossil fuels trapped underneath us over the next few centuries and raised the Earth's temperature by over 10 degrees centigrade, the northern parts of the world would still be habitable, quite likely even more than they would now due to less snow and ice. Antarctica could even be colonised. It would be a shit situation to be in but it wouldn't be the end of humanity.

 

[SinisterGehe]

Global warming + time = human extinction.

No... even if we get 10-15 celsius raise in temperature areas like, Canada, Finland+Scandinavia and Siberia would be like mid-europe. But before that humans would start dying of starvation/disease and other quite basic things.

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My 2 cents.

Humans are resilient granted. But we are not immortal. A simple disease/virus that gets an edge on us can kill us (Without turning us in to raving zombies). Tho remote areas would still survive.

Something that human's could do to wipe themselves out really is to do with nuclear weapons and something like theoretical salt bomb in lower atmosphere. Lots of extremely radioactive material would coat the earth, granted slowly, but it will. And closed environments like bunkers can't hold on forever.

But yellowstone could do it. But we don't know how it would behave. It might not do an explosive eruption at all (But thats something movies and some scientist want to believe). It can slowly erupt.
But even then the sun getting blocked out by ash wouldn't really kill us. Our greenhouse technology and ability to use nuclear power would keep us going.

Only thing that would really kill humanity (in reliable way) is other humans.
We like to think that we are advanced, civilized and sophisticated - that is not true at all. The idea that we are advanced than people few thousands years ago, because we have high arts, philosophy and technology. That is not true at all. Fact is that we are just as willing to kill others (not as individuals but as a groups) than we been.

 

[Timmaaaah]

Environmental science says after we reach a threshold for carbon emissions, the way water is recycled will stop working bit by bit. The water evaporates but not all of it will come back down like it's supposed to. We don't know when this is going to happen or how close we are to it happening but if we reach that point then humanity is inevitably doomed to die very slowly unless we somehow discover a substitute for water.

So yea, global warming plus time.

 

[tm96]

I suggest you look at this showing how nature is trying to kill us https://www.youtube.com/watch?v=Ak6qm9_NaxE

 

[Scarim Coral]

I say it take something big to render the planet uninhabitable to wipe humanity off planet Earth

 

[Korolev]

A huge asteroid would do the trick. If a very large space-rock happens to mosey its way to earth and hit us, then we're doomed. Nukes aren't going to stop a sufficiently large asteroid and we don't have the technology to leave Earth and set up colonies on Mars or Jupiter's Moons.

A very large-scale Nuclear War might kill off humanity. It depends on whether or not a Nuclear Winter would occur and how long it would last. If a sufficiently large scale nuclear war occurs, enough smoke and dust could be generated to wreck the biosphere and humanity might die due to ecological collapse. If the nuclear war involves cobalt-salted nuclear weapons (which are possible, but almost none have been built), then the fallout could persist for thousands of years, pretty much ensuring our extinction (why anyone would ever want to build a cobalt-salted nuclear arsenal is a question I can't answer).

I suppose an extremely contagious, extremely deadly disease could potentially kill off the human race.... but I find it hard to believe.

Hostile Aliens might be able to, but that's an unlikely sci-fi scenario.

So I'm going to go with Asteroid strike or VERY large scale nuclear war.

 

[MysticSlayer]

Resource scarcity, the lack of an alternative for said resource
overpopulation (could be considered as land scarcity, but meh)

Given what we know of overpopulation in other species, it is very unlikely to destroy humanity. The human population would certainly take a hit, but only so far as it takes to actually reduce our numbers to be able to live on the resources.

Environmental science says after we reach a threshold for carbon emissions, the way water is recycled will stop working bit by bit. The water evaporates but not all of it will come back down like it's supposed to. We don't know when this is going to happen or how close we are to it happening but if we reach that point then humanity is inevitably doomed to die very slowly unless we somehow discover a substitute for water.

So yea, global warming plus time.

Maybe I've missed something, but I don't think the water cycle will break down in such a way that we can't access water. The water cycle will certainly go through changes that will have catastrophic effects, and that includes drought, but I don't think scientists are saying we'll slowly lose access to water. It will just be much harder to rely on a single source. Of course, if you can offer a source that says otherwise, I would love to read it.

 

[TheSYLOH]

It is likely impossible for resources to run out to the point for human extinction, at least for the next few million years.
Simply put, as long as there's enough for 300 odd people to survive, then its not human extinction.
Even if we blotted out the sun, poisoned the air and sea and salted the earth, 300 people could probably survive using hydroponics and geothermal/nuclear energy.
Of course 99.9999% of humanity would die, but there's enough left over for genetic viability.
So stuff like super volcanoes, small asteroids, nuclear war and global warming will not cause human extinction, just collapse of human civilization as we know it.
Plague is also unlikely to wipe out all of humanity, the uncontacted peoples would probably survive any plague that wipes out even a plague with 100% fatality rates.

So that leaves the real BIG things that could wipe out humanity.

A gamma ray burst could sterilize earth entirely.
A large enough asteroid, maybe a rogue planet or something could smash the planet hard enough to take out a bunker on the other side of the planet or simply cause the earth itself to break up if it was large enough.
A rogue black hole could wipe out most of the solar system.

Also this is why we want to colonize another solar system, once a species spreads out over a few systems it's not vulnerable to alot of extinction events.

 

[gigastar]

It would take a Chernobyl or Fukushima equivalent happening once about every 8 square miles of land.

I imagine that would do it. And then some.