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Atmospheric CO2 levels accelerate upwards

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Re: Atmospheric CO2 levels accelerate upwards

#461

Post by adrianN »

imgabe wrote: post #453
adrianN wrote: post #272

Earlier quoted context omitted.

Humanity as a species won't end due to climate change. That's a ridiculous assertion. Full scale nuclear war probably couldn't wipe us out completely. Global warming can't either. Billions might die, but humanity will survive almost certainly.

Maybe, maybe not. If you want to split hairs then, how many billion people do you think it's acceptable to kill or cause to suffer so we can have iPhones? People are very bad at estimating the probability of catastrophic events. We base our estimates on things that have happened in the past, but that doesn't help predict things that have never happened before. Hundreds of millions of years of pent up carbon have neve…

That's a false dichotomy. There is no reason to believe that we can't have modern technology without catastrophic climate change. If for example we switched completely to nuclear energy and electric cars we would greatly reduce our carbon footprint to the point where the rest might be offset by planting trees and turning them into charcoal.

Re: Atmospheric CO2 levels accelerate upwards

#462

Post by nol13 »

gambiting wrote: post #51
flukus wrote: post #22

Earlier quoted context omitted.

Is it sensationalism when it's accurately describing something truly sensational?

If both temperature and CO2 levels set new records every single year, then it's stoping sensational - it becomes expected. I'm still hoping to hear solid solutions that will work on a global level, and so far, there aren't any. As a matter of fact, with the global rise of populism it looks like in some areas, the world is going backwards. Leaked UK government memo says the environmental protections and pollution limi…

It's really is depressing seeing the stuff about the great barrier reef etc. Hard to hopeful that we can change course when every indication is that we as a species are not capable of cooperating on such a level.

And even if everyone on earth agreed, who's going to enforce such policies? Would probably require a literal New World Order. Have fun getting the conspiritards (who would have been proven right) to go along with that one.

Hence, my "duck and cover" post elsewhere in this thread, that I sincerely hope was more joke than not.

Re: Atmospheric CO2 levels accelerate upwards

#463

Post by hwillis »

lambdadmitry wrote: post #425
hwillis wrote: post #420

Earlier quoted context omitted.

>At present, the rate of extinction of species is estimated at 100 to 1,000 times higher than the "base" or historically typical rate of extinction (in terms of the natural evolution of the planet) and also the current rate of extinction is, therefore, 10 to 100 times higher than any of the previous mass extinctions in the history of Earth. From wikipedia, Holocene extinction. By what other metric could you possibly…

>Push as much co2 as possible into the air as quickly as possible to change global conditions enough to kill all plants at the same time This makes no sense. How exactly an abundance of CO2 will "kill all plants" given that they are thriving on it? Let's say temperature rises further, like +10C rise. Desertification may kill some plants, sure. In the meantime, huge swaths of Siberia and Canada will stop being permafr…

A 10C rise would put us in the Cretaceous, the hottest time in the past 300 million years. It would melt all ice on earth and the globe would be unrecognizable due to sea rise. This has happened before. It hasn't happened in a couple centuries before.

A 3C rise will kill a lot of plants. A 5C rise will kill most of the plants, and if they can survive the change in biodiversity, the release of methane and CO2 from everything rotting, starving predators, and extreme weather and fire, life on earth might survive and eventually recover after a few hundred thousand or million years.

A 7-10C change over 300 years would, most likely, kill every single thing on the planet that was not transplanted by humans. There are only two ways to survive that without human intervention.

1: Be wide-ranging enough to spread very quickly to areas that become habitable as they open up. A few times a century the entire ecosphere will have to pack up and move to live in the changing climate as floods and deserts move things around. These plants would find it impossible to thrive over the long term and have very little chance of surviving.

2: Literally just tank the entire thing start to finish. For most plants, they will not be able to significantly change their range over this time. In ideal conditions yes, under the massively destabilized climate -disappearing coasts, halting ocean circulation, temperature swings from freezing to sweltering- no way.

The plants in northern Canada would have to be able to survive in tropical heat as well as they currently do in ice and snow. Plants in the tropics would have to survive 100 meters underwater. As the permafrost melts, plants will spread northerly- but the climate will catch up. Ironically it would be better if we killed 99% of plants right now so they could beat the climate. As it stands in a hundred years tropical vines will not be winding their way between New England evergreens- they will be dust in a desert. The pines outside my window will be choking in 40C weather. Boabab trees wouldn't survive in the soil here and Redwoods won't survive in Greenland.

NB: I don't mean to say I think the total collapse of life on earth is likely at this point in time. I think at present even humans are pretty likely to survive what's coming even if we stay our current course for 30 years. However I would give it better than 50% odds that a 7C+ warming would kill multicellular life. Most of the assumptions that you have to make to lead to warming that high necessarily kills everything, eg ice melting, circulation stopping, humans not giving a fuck, etc.

Re: Atmospheric CO2 levels accelerate upwards

#464

Post by btschaegg »

mirimir wrote: post #401
splawn wrote: post #394

Earlier quoted context omitted.

People pointing out the distinction between "killing the planet" and "killing off our species" is what causes my eyes to roll. Seems to me like a moot point. edit: /mute/moot/g

Well, "the planet" = "our species" is a big part of the problem, no?

Well, if you want to spin it positively, that problem might take care of itself. Literally.

Re: Atmospheric CO2 levels accelerate upwards

#465

Post by PeterisP »

Jare wrote: post #348
PeterisP wrote: post #316

Earlier quoted context omitted.

Do you believe that we are heading to near extinction-level event? As far as I have seen, even the most extreme predictions of climate change consequences don't come close to that. I have seen predictions expecting mass forced migrations, decrease in sustainable population, etc; but unless you're literally expecting the vast majority of the worldwide population to die, it's not an extinction-level event, it's not nea…

"Horrible catastrophe" works, but it doesn't stop there. How are humans and our political and military structures going to react? It is debatable how close we have been, during various past crisis, to an actual large-scale nuclear conflict. I don't think we can deny our raw capability to cause a near-extinction-level with our existing technology (nuclear, biological or otherwise). Our political and military ecosystem…

It's worth noting that only USA-Russia full "mutually assured destruction" nuclear exchange has the potential to come anywhere close to an existential threat. A limited nuclear exchange using up the arsenals of all other states does not; a nuclear escalation that results in USA or Russia nuking a non-nuclear state does not, etc. As long as USA and Russia (who between them hold almost all global nuclear weapons) keep their MAD reserves not triggered, it would simply be localized mass destruction on a scale comparable to the city/country destroying mass bombings of WW2.

It would be horrible, it would be comparable to the largest mass killings of 20th century, but it wouldn't be anything that different from what we have survived in the past and it wouldn't be a "near extinction event". "Just" a horrible catastrophe.

Re: Atmospheric CO2 levels accelerate upwards

#466

Post by hwillis »

mirimir wrote: post #452
0xcafecafe wrote: post #439

Earlier quoted context omitted.

As quickly as possible is the key. In the past any changes in temperature were much more gradual.

We're already rather close to "as quickly as possible" :( But plant life? Are you thinking phytoplankton?

Well, for why specifically you'd do it like that: Loading up CO2 in the atmosphere gives you a delayed action on all of this. It's not the CO2 directly, its the fact that you can just start investing into a sudden, massive change easily and then have it all take off exponentially.

If you instead pumped a toxin into the air, you would kill a great deal of things right away but as the concentration of poison rose they would develop a resistance. Thats the slow, traumatic burn, which is global but survivable with enough biodiversity.

If you nuked everything, that would kill almost everything on earth but after a couple decades it'll be relatively survivable again. Life only has to stick around a little bit- spores and seeds is safe places, that by some freak coincidence managed to survive the radiation. Also survivable.

With CO2, nothing happens until suddenly it does. There is a massive change in temperature that kills off biodiversity at a rate higher than ever before- we haven't even hit significant changes and we're experiencing this already. Then, once the biosphere is vulnerable, it gets hit with millenia of instability and extreme problems. There might be pockets that are shielded from this- if they sustained large, diverse populations through the massive initial changes.

It's like the KT extinction on steroids. KT was ~10,000 years- a CO2 bomb would happen even faster and last even longer.

Re: Atmospheric CO2 levels accelerate upwards

#467

Post by btschaegg »

ucontrol wrote: post #215
delegate wrote: post #145

The message I"m getting is not that I have to prepare for something or change energy sources , it's that "our lifestyle is killing the planet much faster than we thought". CO2 levels is just one of a myriad of indicators that are off the scale now. By lifestyle I mean supermarkets and restaurants and iPhones and planes ... all the stuff that we're so proud of as a society. Winning, getting ahead, being number one, ou…

On one hand, I wouldn't completely dismiss the sociocultural norm of prizing competition and pursuit of individual power and status, since even though these motivators seem superficial and lowly to some, they have historically shown to be powerful facilitators of progress and development of humanity, and completely antagonizing them is unwise. We wouldn't be where we are without socioeconomic competition. The iPhones…

In this light, I guess our curse might be that although we were able to part somewhat from the more prevalent "way of nature" (and strive to do so), we won't be able to completely let go of its inherent mechanisms.

Douglas Adams talks about a theory by Mark Carwadine in Last Chance To See[1] in which he tries to explain why the Kakapo has a terribly slow and inefficient mating habit. The idea is that basically, without mechanisms (like predators) to keep them in check, any population that reproduces too fast will trigger a chaos theory-like strongly oscillating population count (coinciding with the resources available per capita at any previous sample point) and thus, most likely, flatline at zero at some point.

Maybe that's our problem: We were able to remove many constraining factors limiting us as a species, but can't let go of the habits that made us succeed so far. Of course, that doesn't only apply to reproduction, but also to resource consumption as a whole. On top of that, our ability to exploit fossil resources only amplifies this effect, because we were able to continue without more immediate consequences so far.

In that sense, one might argue that even without climate change, we would have to change our ways in order for our lifes to remain sustainable.

[1]: https://en.m.wikipedia.org/wiki/Last_Chance_to_See

Re: Atmospheric CO2 levels accelerate upwards

#468

Post by hwillis »

lambdadmitry wrote: post #445
0xcafecafe wrote: post #439

Earlier quoted context omitted.

As quickly as possible is the key. In the past any changes in temperature were much more gradual.

What mechanism for "killing all plants" through sudden atmospheric CO2 increase do you have in mind?

I'm just saying that the biggest, most sudden, longest lasting change in habitability would be made with CO2. The temperature change is what kills the plants, not CO2. It's a bigger temperature change than an asteroid impact and lasts longer.

It's like setting up a bomb, and it has multiple stages. You load co2 into the air until the bomb goes off, causing enough temperature change to cause large desertification. That releases even more stored carbon. That triggers the polar melt feedback, which triggers the permafrost melts, which triggers even more deforestation, which triggers wildfires and weather, which trigger even more polar melting, which wrecks ocean circulation, which fires the clathrate gun, and suddenly there are a handful of species in an earth that is set to random and they will inevitably die out.

Re: Atmospheric CO2 levels accelerate upwards

#469

Post by ChuckMcM »

akiselev wrote: post #49
SamReidHughes wrote: post #25

Earlier quoted context omitted.

Even the high end of predictions aren't expecting an increase in intense weather events bigger than what you might get if you were a bit unlucky over the next century.

Love that spin. The low end of predictions is that the most stable of ecosystems will regularly experience the extreme weather previously reserved for "once-in-a-century" events in the most volatile regions. On the "high-end" is a drastic change in the Earth's shape due to gravity with a meter+ of sea level rise around the equator, runaway exponential heating feedback loops triggered in Siberia and like half the ocea…

Actually its much more likely we'll be hit by a massive CME[1,2] rather than the Sun going Nova. That will destroy massive amounts of automation and compute power all at once which will rapidly destabilize highly automated economies.

But there is zero we can do about that so not worth getting worried over.

[1] https://www.bloomberg.com/view/articles/2017-01-19/how-space...

[2] https://science.nasa.gov/science-news/science-at-nasa/2014/2...

Re: Atmospheric CO2 levels accelerate upwards

#470

Post by eru »

jacquesm wrote: post #290
gnode wrote: post #265

Earlier quoted context omitted.

I disagree that it isn't happening. Solar PV capacity is growing rapidly. Vehicles are increasingly powered by electric batteries. These things were all prohibitively expensive for most people in Western countries, but their declining cost has made them more affordable and more used.

Vehicles are increasingly powered by coal plants. Electric batteries don't power anything, they're best compared to empty buckets.

Do you know if anybody ran the numbers? Centralized coal plants might still be more efficient than micro-petrol plants in every car?
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