What's going to change in a Earth that's 8c hotter?

[TheMeInTeam]

This is why I'm so deeply skeptical of claims that a warmer world means Siberia would be a productive, habitable place. That is just way too specific of a claim to make based on available data and projections.

I think at the very least 'species wipe' is on the table with nuclear winter. Radiation won't confine itself to the areas that are directly nuked and we're already a pretty fragile and cancer-prone species. And I think the further we go forward in time, the more vulnerable we'd all be to dying for lack of civilization. I'm a smart guy, but I think I'd probably starve to death pretty quickly should society collapse as I doubt I could figure out foraging or farming fast enough to make it, even if the fallout from a nuked LA didn't lethally contaminate everything around me. As more and more people join modern society, that means there are less and less people capable of making it on their own absent the trappings of modern society. Falling numbers of nuclear weapons does make species wiping less likely overall, though. And I hope we continue that trend..

I'm not sure even 90% loss of population would suffice for species wipe. It's unlikely everywhere in the world gets nukes and the winds will heavily bias which places get fallout.

Even worse than direct radiation is probably food loss. Nuclear winter will badly cripple yields from arable land + how much land is arable (latter due to both radiation itself + also less sunlight/temperature difference). So even after direct deaths + radiation deaths there will be mass starvation + conflict over remaining land that's survivable. But in this scenario there's still enough land to sustain populations larger than several centuries ago. Maybe the conflict results in total collapse of all humans outright but that wouldn't be my first guess.

It'd make historical events like the black plague look like a picnic though.

 

[Berzerker]

The Earth's obliquity (tilt) changes over time (by ~2-3 degrees) so about 9-10 thousand years ago the sun appeared further north and south in the sky on the solstices. That was the last time the Sahara got more rain from the monsoons. Current theory says people living in the Sahara were driven out 6-7kya as the monsoons receded southward leading to Egypt's civilization. Pumping CO2 into the atmosphere can help drive monsoons deeper into the Sahara.

 

[Zardnaar]

This is why I'm so deeply skeptical of claims that a warmer world means Siberia would be a productive, habitable place. That is just way too specific of a claim to make based on available data and projections.

I think at the very least 'species wipe' is on the table with nuclear winter. Radiation won't confine itself to the areas that are directly nuked and we're already a pretty fragile and cancer-prone species. And I think the further we go forward in time, the more vulnerable we'd all be to dying for lack of civilization. I'm a smart guy, but I think I'd probably starve to death pretty quickly should society collapse as I doubt I could figure out foraging or farming fast enough to make it, even if the fallout from a nuked LA didn't lethally contaminate everything around me. As more and more people join modern society, that means there are less and less people capable of making it on their own absent the trappings of modern society. Falling numbers of nuclear weapons does make species wiping less likely overall, though. And I hope we continue that trend..

Nukes aren't as bad as what a lot claim, there will be survivors.

The Southern hemisphere would be reasonably uneffected. New Zealand for example even if it got hit by a couple of nukes could soak that.

Nuclear winter wouldn't be pitch black more crop failure to various degrees.
Humans would survive in various areas.

 

[Zardnaar]

The Earth's obliquity (tilt) changes over time (by ~2-3 degrees) so about 9-10 thousand years ago the sun appeared further north and south in the sky on the solstices. That was the last time the Sahara got more rain from the monsoons. Current theory says people living in the Sahara were driven out 6-7kya as the monsoons receded southward leading to Egypt's civilization. Pumping CO2 into the atmosphere can help drive monsoons deeper into the Sahara.

Sahara probably wasn't green as such just relative to what it is now.

It was probably a bit more like the Savannah in southern Africa.

 

[TheMeInTeam]

It was probably a bit more like the Savannah in southern Africa.

It's in the same latitude as savanna parts of India, so we might expect something similar to those eventually. It would take some time to grow like that though. Plants themselves hold some water and keep a feedback loop in regions with that level of rainfall.

On the face of it fears of more desert on average due to more heat + C02 are a little strange. If we have more water via melted caps and more atmospheric moisture (which we should expect with more heat and surface area of water) a global increase in desert surface area isn't a top worry. Sea levels, habitability of portions of the world, and the sheer cost/damage of localized climates should be bigger worries.

Another very significant worry that doesn't get talked about as frequently but is still important is that fossil fuels are finite. We use oil for plastics and other very useful goods, not just fuel. And while better tech has kept the supply going, it's not bottomless. Eventually we'll run out, or make it so scarce that it's impractically expensive. There's some real incentive for developing price-competitive renewable energy. Though you still have to be careful, renewable still isn't necessarily good for the environment (aka burning wood). I've read that world has more trees now than pre-industrialism since wood was leaned on more heavily and now trees are replanted more consistently, not sure if that's true or not.

 

[Mouthwash]

I've read that world has more trees now than pre-industrialism since wood was leaned on more heavily and now trees are replanted more consistently, not sure if that's true or not.

 

[Estebonrober]

It is possible for nuclear winter to wipe humanity our, yes even new zealand. It depends on how many are used. The US if it launched everything could cause a 99% extinction level event. That would definitely include humans.

I mean if we are just shooting crap around about what could happen SevenEves by Neal Stephenson has a neat one where an asteroid obliterates the moon and erases life on Earth basically for hundreds of years. Its a fun read.

Yes Forests in Europe are making a comeback due to not relying on wood. Neat map! I love maps.

 

[Gorbles]

Nukes aren't as bad as what a lot claim, there will be survivors.

This is like saying "getting a shot a lot isn't as bad as people claim, you'll still have a couple of unperforated organs"

Nukes are as bad as people are claiming. Assuming the question is the survival of the modern human society, of course. If that's not the underlying assumption, and people are happy with sacrificing themselves and whoever else is "unlucky" enough to die as a direct or indirect result of nuclear blasts, then sure, okay. All I can say is disagree, and share @hobbsyoyo's hopes about decreasing nuclear stockpiles.

 

[Akka]

I'm not sure even 90% loss of population would suffice for species wipe.

Of course it wouldn't. It would barely bring us back to XIXth century population...

 

[Gorbles]

Of course it wouldn't. It would barely bring us back to XIXth century population...

Global population estimates for 1800 to 1900 start at (around) 1 billion and increase to (around) 1.65 billion by the end of the century. That's a huge reduction on our current global population on the face of it, without debating the harm done to humanity in the long run (i.e. people who will die due to a lack of resources and / or care as a result).

Personally, I think wiping out between 79% of people on the planet (most charitable interpretation; 1.65 billion as per global population at the turn of the 20th century, surviving from the current 7.7 billion) is more in line with what @Estebonrober is saying than your claims to the contrary, Akka.

 

[Zardnaar]

This is like saying "getting a shot a lot isn't as bad as people claim, you'll still have a couple of unperforated organs"

Nukes are as bad as people are claiming. Assuming the question is the survival of the modern human society, of course. If that's not the underlying assumption, and people are happy with sacrificing themselves and whoever else is "unlucky" enough to die as a direct or indirect result of nuclear blasts, then sure, okay. All I can say is disagree, and share @hobbsyoyo's hopes about decreasing nuclear stockpiles.

I'm talking about nukes as an extinction level event.
You could kill 95% of the human species and they can bounce back. Might take several thousand years but there you go.

Dropping a few nukes on each other would probably harm the planet less than our existence as a species.

 

[Imaus]

Nuclear war won't wipe out humanity. It'll set back civilization, and not even a few tech levels. Everyone and their uncle can rig up electricity now or make ethanol. It's just that the massive structures we've come to enjoy will be gone as everything breaks down. More people will die of that - famine, chaos - but many will still survive; even close to where nukes fell. So long as they can scrounge up the food and water. Of THOSE, sure most of them will probably die of cancer down the road but honestly we're already a cancer-ridden species so few will notice the difference, save the academics.

There's just so much junk, stuff, institutions, people, information, settlements, et al around this world now that a nuclear war will be a major disaster, but nowhere near a stopper. And every year the world continues to develop and grow and becomes more multi-polar (even if not totally self-sufficient) that such redundancy, that plethora of hardiness by sheer numbers, increases as well.

 

[Estebonrober]

Carl Sagan was one of the first people to recognize this point in a commentary he wrote on nuclear winter for Foreign Affairs.7) Sagan believed nuclear winter could cause human extinction, in which case all members of future generations would be lost. He argued that this made nuclear winter vastly more important than the direct effects of nuclear war, which could, in his words, “kill ‘only’ hundreds of millions of people.”

Sagan was however, right that human extinction would cause permanent harm to human civilization. It is debatable whether nuclear winter could cause human extinction. Alan Robock, a leader of the recent nuclear winter research, believes it is unlikely. He writes: “Especially in Australia and New Zealand, humans would have a better chance to survive.”8) This is hardly a cheerful statement, and it leaves open the chance of human extinction. I think that’s the best way of looking at it. Given all the uncertainty and the limited available research, it is impossible to rule out the possibility of human extinction. I don’t have a good answer for how likely it is. But the possibility should not be dismissed.

https://fas.org/pir-pubs/risk-nuclear-winter/

It just depends on how much dust gets up there and how long the sun gets blocked out.

 

[Zardnaar]

Carl Sagan was one of the first people to recognize this point in a commentary he wrote on nuclear winter for Foreign Affairs.7) Sagan believed nuclear winter could cause human extinction, in which case all members of future generations would be lost. He argued that this made nuclear winter vastly more important than the direct effects of nuclear war, which could, in his words, “kill ‘only’ hundreds of millions of people.”

Sagan was however, right that human extinction would cause permanent harm to human civilization. It is debatable whether nuclear winter could cause human extinction. Alan Robock, a leader of the recent nuclear winter research, believes it is unlikely. He writes: “Especially in Australia and New Zealand, humans would have a better chance to survive.”8) This is hardly a cheerful statement, and it leaves open the chance of human extinction. I think that’s the best way of looking at it. Given all the uncertainty and the limited available research, it is impossible to rule out the possibility of human extinction. I don’t have a good answer for how likely it is. But the possibility should not be dismissed.

https://fas.org/pir-pubs/risk-nuclear-winter/

It just depends on how much dust gets up there and how long the sun gets blocked out.

Life survived the asteroid that hit the earth. IIRC a nuclear war is small potatoes by comparison.

Global warming won't do us it.

The only thing that could IMHO is something that poisons the atmosphere.

I don't think there's enough warheads. Even New Zealand would survive 6 or 8 and we would be very low priority.

Most if not all would be in the northern hemisphere.

 

[MaryKB]

I heard New Zealand's now target #1 because people think that's where Sauron lives?

 

[Estebonrober]

Life survived the asteroid that hit the earth. IIRC a nuclear war is small potatoes by comparison.

Global warming won't do us it.

The only thing that could IMHO is something that poisons the atmosphere.

I don't think there's enough warheads. Even New Zealand would survive 6 or 8 and we would be very low priority.

Most if not all would be in the northern hemisphere.

Your and other's optimism on this is weird, but this is a hijacking of the thread isn't it? Global warming can shift the atmospheric makeup and result in a near total extinction event it has happened before it seems.

https://earth.stanford.edu/news/what-caused-earths-biggest-mass-extinction#gs.6rkill

https://phys.org/news/2018-09-end-permian-extinction-earth-species-instantaneous.html

https://www.britannica.com/science/Permian-extinction/Alteration-of-the-carbon-cycle

 

[Zardnaar]

Your and other's optimism on this is weird, but this is a hijacking of the thread isn't it? Global warming can shift the atmospheric makeup and result in a near total extinction event it has happened before it seems.

https://earth.stanford.edu/news/what-caused-earths-biggest-mass-extinction#gs.6rkill

https://phys.org/news/2018-09-end-permian-extinction-earth-species-instantaneous.html

https://www.britannica.com/science/Permian-extinction/Alteration-of-the-carbon-cycle

Humans can adapt, as long as we can breathe the atmosphere.

Killing 95% still leaves around 350 million humans. 99% leaves about 70 million.

At one point I think we had 10 000 humans.

 

[Gorbles]

I'm talking about nukes as an extinction level event.
You could kill 95% of the human species and they can bounce back. Might take several thousand years but there you go.

Dropping a few nukes on each other would probably harm the planet less than our existence as a species.

Okay, but what I don't get is why. There are only a few scenarios that would cause an extinction-level event, and that would likely affect the majority of mammalian species on the planet.

We might well survive. But at what cost? Why are we discussing the percentage to which humanity might survive in fragmented enclaves across what remains of the world, when in that likelihood the Internet as we know it won't function and most of us, or our children, or grandchildren (however it works out) will be dead?

It seems to be a very apathetic, almost nihilistic view to take on things, in my opinion. Just because humanity might technically survive such an event, doesn't mean we can't view it with horror. Language such as "bounce right back" is basically as pointless as saying "it's the next generation's problem" (which, perhaps ironically, is why where we are with climate change).

 

[Zardnaar]

Okay, but what I don't get is why. There are only a few scenarios that would cause an extinction-level event, and that would likely affect the majority of mammalian species on the planet.

We might well survive. But at what cost? Why are we discussing the percentage to which humanity might survive in fragmented enclaves across what remains of the world, when in that likelihood the Internet as we know it won't function and most of us, or our children, or grandchildren (however it works out) will be dead?

It seems to be a very apathetic, almost nihilistic view to take on things, in my opinion. Just because humanity might technically survive such an event, doesn't mean we can't view it with horror. Language such as "bounce right back" is basically as pointless as saying "it's the next generation's problem" (which, perhaps ironically, is why where we are with climate change).

People lived without the internet lol.

I think the messaging on climate change can be counter productive.

We've been hearing Doom and gloom since at least the early 90s.

Similar with nukes are bad.

It's turned into a cry wolf thing, most people don't relate to it and it goes into the to hard basket.

 

[Gorbles]

People lived without the internet lol.

I think the messaging on climate change can be counter productive.

We've been hearing Doom and gloom since at least the early 90s.

Similar with nukes are bad.

It's turned into a cry wolf thing, most people don't relate to it and it goes into the to hard basket.

Maybe, if we've been hearing these things for coming up 30 years, they're probably things that should be debated less then?

I mean, heaven's sake. Nukes are bad. They're weaponised boulders of radioactive energy that explode with an incredible force incomparable compared by the size of payload to every other bomb going. I don't get why you think that's a helpful comparison to climate change. I just don't understand.