• Sir_Osis_of_Liver
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    747 months ago

    Positive feedback loops, how do they work?

    We’ve known about this for decades. An example: heating causes permafrost to melt releasing CO2 and methane, which cause more heat to be trapped, which melts more permafrost, which releases more green house gasses, etc.

    Positive feedback loops tend to be very unstable, and can lead to runaway situations.

    • @Notyou@sopuli.xyz
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      287 months ago

      Can’t wait for all those ice caps to go away and stop reflecting all the heat that they do reflect being white. It’ll just add to it.

    • @burgersc12@sh.itjust.works
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      77 months ago

      The article goes out of its way to claim this isn’t the case. Theres a line that says something like there is no extra heat in the pipeline.

      • Spzi
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        107 months ago

        I followed the links in that quote:

        Climate models have consistently found that once we get emissions down to net zero, the world will largely stop warming; there is no warming that is inevitable or in the pipeline after that point.

        Neither addresses tipping points. They seem to talk about something else entirely, like wether a model assumes constant atmospheric concentration, or constant emissions, that kind of difference.

          • Spzi
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            27 months ago

            There’s so much wrong with comments starting with “So you …”.

            Yes, I’m not a climate scientist. I don’t have the time and energy to read all the relevant papers, nor do I need to do so to participate in the discussion on Lemmy. Sometimes I do, but I’m not obliged to, and you’re not in a position to judge.

            It’s great though that you read the paper. Can you support your claim with quotes from it? After all, I don’t trust random dudes.

              • Spzi
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                27 months ago

                Nah, that’s you. Oh, ok. I did not understand you wanted to point out that. This is confusing. Maybe you misunderstood my initial comment.

                I’m not agreeing with the quote from the article, but speaking against it.

    • People are really bad at conceptualizing exponential change from feedback. Our brains expect incremental change. I think that’s one of the reasons people can’t know accept what is happening.

      “I know things are changing, but it’s only a bit each day, and it can go like that for years and it won’t be that bad.”

  • IninewCrow
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    687 months ago

    As much as this news disturbs me … the thing that disturbs me most is that most of the world will ignore it.

    Humanity won’t do anything about any of this until millions die and mass migrations start happening due to extreme weather events.

    • Track_Shovel
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      337 months ago

      COVID was the perfect microcosm for climate change action. COVID killed a shit-pile of people really quickly. Humans are wired to acknowledge pressing matters (like a pandemic), while more abstract concepts, and things with delayed consequences get pushed to the wayside.

      It make sense, why we are the way we are. Who cares about where your meal next week is going to come from, when you’re a caveman running from a lion?

      Does it make us any less dead? nope. Just the timing is in question.

      • @freebee@sh.itjust.works
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        187 months ago

        Even covid was already too hypothetical and abstract and too far away in time and space for millions of people to act cautiously. Climate change is further away still… When it becomes very noticeable, it’s far too late: hawaii fire level stuff before people actually realise it’s fucked.

          • @vivadanang@lemm.ee
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            67 months ago

            the number of chuds I’ve met that really, really think it was some kind of space laser and not a wildfire driven by hurricane winds and crippling heat is fucking depressing. people I volunteer with who I thought were rational humans… what in the fuck

        • Track_Shovel
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          -97 months ago

          Fun fact! Mines take climate change into consideration for all their engineering and revgetation designs

          #TheEarthHasAlwaysHadClimateChange

            • Track_Shovel
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              47 months ago

              I think I should have added ‘/s’.

              I’m no denier.

          • IninewCrow
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            37 months ago

            Correct, there has always been climate change … most of the change in the past happened over a millennia … and some of it was catastrophic with changes happening over short periods of time and it usually meant the death of millions of life forms

            The current climate change period we are living in is human made most definitely … if our descendents survive, (or whatever new species takes over … or even if artificial intelligence takes over) tens of thousands or millions of years from now - when they look back at the geologic record, they’ll wonder why there was a weird global distribution of radiation and toxic material everywhere and they will notice the fact that a large percentage of species everywhere died off at around the same time we started to develop into the technological / communications age

            Climate change has happened in the past … what most people that say this leave out is the fact that it tends to kill off many creatures that can’t adjust to the changes … and if the changes are dramatic enough, it tends to cause a mass die off of creatures on the planet … and what many of these proponents tend to conveniently leave out is that WE may be one of those species that will die out because we won’t be able to survive these changes. We’re technologically smart and we are creative … but this isn’t Hollywood, we won’t pull off a last minute super hero, Hail Mary, super smart group of people get to save the day at the last possible moment … if things fall apart, it will happen slowly over decades until we all fall apart, society fails and we all just slowly fade away because there is nothing liveable left to save ourselves.

    • @Nudding@lemmy.world
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      307 months ago

      I’m less optimistic than you, I think we will continue to increase fossil fuel usage, even though millions are dying and being displaced.

        • IninewCrow
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          167 months ago

          That’s the kind of logic I expect to see in the coming decades.

          People will argue the details, debate the topics, defend finances and the economy … all while the world falls apart and people die, are actively dying or will live shorter lives.

          Humanity will fade into obscurity as we all fight with one another.

      • Hell yeah.

        Thats for sure. Many finance analysts predict 3 digit oil prices.

        Investments will ramp up once demand puts pressure on the price.

        And fossil fuel industry will be the most profitable one again.

        WE CANT EXPECT OUR SYSTEM TO CHANGE WITHOUT CHANGING THE SYSTEM.

      • föderal umdrehen
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        7 months ago

        What will we need all those fossil fuels for? Surely, at some point in the early 2030’s, as capex for PV/wind turbines/heat pumps/batteries decreases and opex remains low, most people will have realized that fossil fuels are personally costing them money. The only business remaining may be plastics rather than electricity and heat. Granted, it’s entirely possible fossil fuel companies successfully double down on plastics (which is what many are planning already).

        • @Nudding@lemmy.world
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          37 months ago

          I mean, thanks to citizens united and “lobbying”, oil companies control the US, and therefore the world. So no, I don’t expect to see much change.

    • interolivary
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      7 months ago

      Humanity won’t do anything about any of this until millions die and mass migrations start happening due to extreme weather events.

      We won’t do anything even then.

      Well, not anything that’d help, at any rate. The worse things get, the more people will vote for conservatives and populists who will sell them easy solutions, which will likely consist of mass violence and rolling back environmental regulations because they inconvenience their voters. The only thing that will actually help will be the inevitable collapse of industrial society at this scale, but to get there hundreds of millions if not billions will die pointless deaths, especially if nuclear weapons are involved in the collapse.

    • Otter
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      727 months ago

      relevant bit (I think, I didn’t read the entire thing):

      And while many experts have been cautious about acknowledging it, there is increasing evidence that global warming has accelerated over the past 15 years rather than continued at a gradual, steady pace. That acceleration means that the effects of climate change we are already seeing — extreme heat waves, wildfires, rainfall and sea level rise — will only grow more severe in the coming years.

      • @RedditWanderer@lemmy.world
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        7 months ago

        This is nothing new though. Climate Scientist have ALWAYS been fearing a runaway effect. It has a wiki page and all. The author isn’t wrong, but it’s click bait. It’s not telling us anything new.

        • @ryven@lemmy.dbzer0.com
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          167 months ago

          I think the difference is that, at least when I took a class on this (coincidentally about 15 years ago), we talked a lot about how there was likely to be a runaway effect. This article is saying that the climate measurements from the last 15 years provide evidence that the predicted runaway effect is, in fact, happening.

          • cannache
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            27 months ago

            I would like to buy 50 years time please 🥺, if people can wage war, build monuments, AI and trains all in under 30 years then we still have some what a slim chance of working through some of the climate change problems without committing mass suicide of some sort

          • @HughJanus@lemmy.ml
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            17 months ago

            All that’s going to do is burn the credibility of the author.

            Regardless, no one is going to read this and suddenly change their mind, because we don’t have an education problem, we have a culture problem.

      • @Steeve@lemmy.ca
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        27 months ago

        I thought we knew this? I remember hearing that we’re just now feeling the effects of greenhouse gas emissions from the 80s, and emissions have drastically increased since then.

    • Tar_Alcaran
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      127 months ago

      Ah, my first thought was “Well, either we’re less doomed, or more doomed. Probably gonna be the second”.

    • @Risk@feddit.uk
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      97 months ago

      It ends on a positive though - if the world gets to net zero, then (apparently) no further warming will occur (does this mean runaway warming -from lack of reflection via ice sheets, methane release from previous permafrost zones, etcetera - is no longer expected?).

      We just need to push our politicians harder. Poverty and climate are intrinsically linked - we can improve things in the everyday person’s life with green investment and policy.

      • Rhaedas
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        157 months ago

        Here’s the problems with net zero. First, it’s a marketing term more than anything. But assuming it was an obtainable goal, it requires carbon removal techniques that have been shown by prototype and basic math to not be scalable to the task. Making another assumption that such emissions or their equivalent could be removed, we would need to go far beyond net zero into negative emissions to start chipping away at not only continued natural emissions from the mentioned runaway feedback loops already set in motion, but the historical carbon that still remains fro the last century or so of our pollution. If just net zero isn’t scalable, the latter is magnitudes greater and impossible.

        Net zero is the new “1.5 limit”. It’s an easy to remember catch phrase for a goal post on wheels. As we pass the old 1.5 mark the new one is used to distract from continued growth of population and consumption, catering to the wired tendencies of our species to procrastinate when danger isn’t immediately in front of us. “They’ll fix it”.

        I think the idea that if we can reduce our emissions warming and all that comes with it will also stop is also a subtle marketing being spread because most people don’t understand that we’re not the sole source of warming, we were just a small catalyst that started the reaction. And with most chemical reactions, at some point the catalyst isn’t needed any more to sustain the rest of the reaction. We could stop all emissions right now (whether that be voluntary or not) and the Earth will continue to warm for decades or more just from environmental inertia and breakdown of the system, and then from the addition feedbacks that starts.

        The only “fix” for the CO2 issue (which is only part of the problem, but the focus here) is to remove and sequester enough carbon to bring us down to 300 ppm or less, aka preindustrial levels. Put everything burned by our industrial age back into the ground. Entropy alone says that won’t happen, calculating the numbers of how much carbon that means is mindblowing. We throw around the giga- prefix like it’s nothing, and yet the total carbon we would have to remove gets into the tera- and possibly peta- levels. It’s insane.

        Net zero is a scam, nothing more. I’m not at all saying we shouldn’t change, but don’t believe anyone selling you a solution, as change means adaptation and preparation for a different and hostile world, not some science “fix” that will let us keep doing what we’ve always done.

        I’m sure my rant that started as a short reply will get some responses of “what about ___?” Good luck showing me something new that changes the basic math of the problem. It’s looking into some of these potential solutions and finding out the real problem that turned me into a hardened skeptic of anything “new”. Show me the math that can tackle the numbers, then I’ll consider it. In the end you can’t fool Nature.

        • @LuckyJones@lemmy.world
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          117 months ago

          It’s insane.

          The thermodynamic minimum amount of energy needed to extract CO2 at 450 ppm is 120 kWh per tonne. Current experimental carbon capture plants run at about 5 % efficiency. If we assume we can double their efficiency and can magically produce as many plants as we need, to remove 20 Gt of CO2 per year (half our emissions) we would need 24,000 TWh of energy per year.

          That is the entirety of the world’s electricity production. To remove half our emissions.

          Carbon capture is a non-runner.

          • @AngryCommieKender@lemmy.world
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            7 months ago

            Hemp. Nature provides a way to do many things that technology can’t do efficiently. Hemp will capture carbon and store 80% in the roots. We would need 5 billion acres of hemp production to remove double our current emissions, I did the math a year ago. That would only be achievable with floating greenhouses, as far as I can figure, but if we hit net zero, then hemp looks much more doable in terms of a long term solution.

            Edit: Also marijuana, and we can still use both plants the way we currently do, just store the roots in drums and fill up Yucca Mountain, since we aren’t storing nuclear waste there.

          • Rhaedas
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            47 months ago

            Thanks for an example of the numbers. And to point out, the entirety of the world’s production of electricity is still over 60% from fossil fuels, so using that energy to undo emissions is ideally a wash, and realistically still an increase. And that’s if we turned all of the energy to carbon removal from everything else, which would never happen.

            • @Risk@feddit.uk
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              17 months ago

              Well yes, but isn’t the point to use progressively less fossil fuels - net zero implies we get to a point where we stop making things worse.

              From there, then we can start making things better.

              • Rhaedas
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                27 months ago

                Net zero is simply where the emissions we still are emitting are being countered by “something” to have a flatline of human sourced emissions total. Likely the same magic that the IPCC is still counting on, carbon removal tech. It’s almost 2024 now and we’re starting to see the accumulation of the damage we’ve done, mainly because things like the oceans have hidden it for so long and are now failing. Time is up.

                We absolutely need to reduce fossil fuel use NOW, and as much as possible each year. The damage that will do to our society might be a price no one is willing to pay though, we’re very heavily dependent on it, more and more each year. Just a linear decrease means in five years we better be down to 30 gigatons annual emissions, and five more down to 20 gigatons. There isn’t a way to do that and keep our modern society (and the up and coming third world industrial countries).

                Discussing a Catch-22 situation can become heated, because people don’t want the problems pointed out to them without some answers to consider. I’m sorry I don’t have any to give. Any that I’ve ever seen or been presented with are always false hopes, it’s a big mess we humans have created.

          • @APassenger@lemmy.world
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            27 months ago

            We’re in a bad way until we have ubiquitous fusion, widely adopted nuclear, or some other non-CO2 emitting energy.

            And those are really tall orders. We need a Manhattan + Man on Moon level effort to even begin to turn this thing around and I’m not see the urgency or leadership from people who’d need to get things rolling.

      • Spzi
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        37 months ago

        if the world gets to net zero, then (apparently) no further warming will occur (does this mean runaway warming -from lack of reflection via ice sheets, methane release from previous permafrost zones, etcetera - is no longer expected?).

        I followed the links in that quote:

        Climate models have consistently found that once we get emissions down to net zero, the world will largely stop warming; there is no warming that is inevitable or in the pipeline after that point.

        Neither addresses tipping points. They seem to talk about something else entirely, like wether a model assumes constant atmospheric concentration, or constant emissions, that kind of difference.

        “Runaway warming”, as I understand it, merely describes the outcome, the effects, while being agnostic about the causes. My current understanding is, we ruled out one possible cause. Tipping points like sea ice or methane hydrate are still on the table, AFAIK.

      • @Pot8o
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        17 months ago

        Now there’s a movie reference I haven’t heard in a long time.

  • @insomniac@sh.itjust.works
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    597 months ago

    These threads are such a shit show. No one reads the article and then just has the conversation they want to have, other people who didn’t read the article think they’re summarizing it, and everyone walks away dumber.

    • @silence7OPM
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      147 months ago

      Online discourse tends to be like that

    • @mayo@lemmy.world
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      67 months ago

      I read the article but it doesn’t say much that hasn’t been said a thousand times before.

      Thread is a mess though I’ll agree on that.

    • knexcar
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      7 months ago

      Because why would I read an article that’s probably riddled with ads, when I could read a quick unbiased fact in the headline (edit: and an image) and get expert commentary in the comments (that often builds upon or refutes the article anyways)?

      • @silence7OPM
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        Run an ad blocker. Firefox + uBlock origin does wonders.

        Reading the article is a prerequisite to not being taken by disinformation.

        • knexcar
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          -27 months ago

          Sadly I’m on an iPhone, though I do have one on my desktop.

          • @silence7OPM
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            37 months ago

            I think adblock plus works on Safari on the iPhone.

          • @M137@lemm.ee
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            -27 months ago

            adblockers have been a thing on iPhone for years, even I know that and I don’t have one. How are you this ignorant?

  • WytchStar
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    317 months ago

    We’ve discovered the breaking point of paradise. Hope the next sentient species is a little less selfish.

    • @Nyssa
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      227 months ago

      Unfortunately, I don’t know if it would be possible for another species to reach our level of technology or civilization. We built up our society off of easily accessible energy resources (surface-level coal being our first source of industrial energy). This energy excess allowed us to develop other sources of energy, solar, wind, nuclear, etc. But if you tried starting from zero again, you could never get to this point, at least along the same path, as you need a high level of technology to access any available energy resources. Thus, if any new species took our place, they could only ever rise to the level of the pre-industrial revolution.

      • @dangblingus@lemmy.dbzer0.com
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        117 months ago

        At the very least, even basic electricity production requires copper windings. Which requires copper wire. Which requires refined copper. Which requires copper ore. Which requires copper mining.

        Generations of people with manual tools will need to die in the mines for enough electricity to be generated to run a small medical clinic, let alone get post-climate humans to a point of modern civilization.

        • @notabot@lemm.ee
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          147 months ago

          While it’s definitely bleak, it’s not quite as bleak as that. Remember that we’re leaving behind vast amounts of ‘waste’, much of which contains things like copper, aluminium, steel and other useful components in relatively easily refinable states.

          Future civilisations will be digging through our waste, wondering why we were so profligate, but glad to have it all to hand.

          • @xapr@lemmy.sdf.org
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            37 months ago

            I had thought about this scenario before too, but now I can think of many other scenarios where this doesn’t happen.

            Examples: a complete loss of most of humanity’s technological know-how to where we don’t even know how or why use those materials, loss of knowledge of where many of these (mostly difficult to harvest?) resources are buried, and warring between factions for access to these resources. Not only each of those scenarios individually, but also a combination of all of them plus other factors working against this happening.

            I think that the eventual best case scenario for humanity will be going back to pre-industrial living and technology.

            • @notabot@lemm.ee
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              67 months ago

              Those are fair points, but consider that they just put the next civilization at the same level we were; we didn’t have the technological know-how until we invented it, we didn’t know how or why to use different ores until we worked it out, we didn’t know where the ores were to be found until we gound them, and harvesting pre-refined material is much less intensive than that, and well, we’ve warred, and continued to war over access to resources.

              Basically, we’ve dug up lots of the easily accessible ore, which has a low density (you need to dig up maybe 4 tonnes of rock to get a tonne of iron ore, and that is only between 50-75% iron, for instance) and buried it more shallowly, and at higher density. There’s still work to do to extract it, but it’s manageable with fairly low tech.

              Energy sources are a little more complex, but we’ve bound up a lot of hydrocarbons in plastic and the like, which should be usable, if not ideal in their raw form.

              • @xapr@lemmy.sdf.org
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                47 months ago

                Those are good points too, that I hadn’t thought about. I thought it would be challenging, but maybe it wouldn’t be as challenging as I had imagined it.

                But who knows, maybe we would be better off going back to pre-industrial times anyway?

                • @notabot@lemm.ee
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                  37 months ago

                  But who knows, maybe we would be better off going back to pre-industrial times anyway?

                  But how would I find interesting conversations on Lemmy if my highest tech gadget was a loom?!? :)

      • @Rolder@reddthat.com
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        57 months ago

        Perhaps if it’s a few million years later and all us dead humans have turned into coal and oil, like the dinosaurs of the past.

      • @xapr@lemmy.sdf.org
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        37 months ago

        That’s a good thing, right? The vast majority of the results of technology and “civilization” has turned out to be nothing but a curse on this planet.

        • @Nyssa
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          27 months ago

          To an extent, but we have the chance of transitioning into a solar and wind society and remediate that damage. Subsequent species would not have that potential.

          • @xapr@lemmy.sdf.org
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            17 months ago

            I wasn’t even talking about subsequent species, but our own species in the future. As for solar and wind, I’m afraid that the way that population growth and energy consumption growth interacts with the material requirements for solar and wind, that is also going to hit a wall in the not too distant future.

      • @jandar_fett@lemmy.world
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        17 months ago

        It’s really actually kind of fascinating when you think of how that energy source was made, with a mass die off of carbiniferous (I think) rootless trees, aka scale trees that all fell due to not being able to support their own weight probably because the incredible amount of oxygen in the atmosphere at the time, then the carbon from those trees got buried and pressed into “fuel diamonds”, plentiful and packed with all the energy a type 0 civilization would ever need, but the very fact that using the results of that die off to power our species unabashedly, has doomed us, because we finally reached that ever important ceiling that ecologists/biologists are always talking about. We thought we outsmarted evolution and nature, but we are just as much a part of it as any other being or object.

        It’s kind of beautiful to me.

      • @Fungah@lemmy.world
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        17 months ago

        They wouldn’t be able to take the same oath we did but that isn’t saying they could never get to where we’re at more or less.

        The enlightenment spawn the industrial revolution but it didn’t necessarily have to. Scientific inquiry could have eventually lead us to somewhere near where we’re at now without fossil fuels. The path would look wildly different and there’s a fairly high likelihood mass slavery could play a role in that but it’s still possible.

        Kind of a tangent here but the book children of time goes into some depth on how the author thinks a race of super intelligent spiders could overcome many of the same hurdles we had to in wildly different ways to become a space-aring civilization. It’s science fiction and obviously not an in depth study into how feasible it all would be but it did get me thinking that there is more than one way to skin a cat.

        • @Nyssa
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          17 months ago

          I disagree. To unlock workable solar and wind powered electricity, you need something to carry you energetically through the ‘tech tree.’ I simply don’t think you can get to that level of technology without some fossil fuel use.

          • @Fungah@lemmy.world
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            07 months ago

            Solar maybe not but i could see an intelligent species figuring out that if they wrapped some copper wire around something under a waterfall that stuff happened.

            Hell maybe they’d skip most of what we’ve done and just stick uranium into cars.

            I really don’t have enough scientific knowledge to offer in depth arguments as to the how of it but I think it’s reasonable to assume that at least some. If not most. Of the discoveries we take for granted in modern times could have happened without oil. It would be a very different world for sure. Though.

    • @jandar_fett@lemmy.world
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      17 months ago

      What paradise? Us in the developed world, that are fortunate to have our basic needs met by mostly luck of the draw, are in a bubble. It’s never been paradise, but now it’s going to be utter hell.

  • Neato
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    227 months ago

    Heating is accelerating. IF we stop adding greenhouse gases to the air, the heating should stop. It won’t go back down without removing massive amounts of CO2, though.

        • @narp@feddit.de
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          47 months ago

          Yes, net zero, which some companies and countries pledged to reach until 2050. Unfortunately it’s delusional, because they count on technological fixes being invented in the future and until then it’s “business as usual”.

          Industries like cement, chemical and steel will never be net zero without carbon capture for example.

          • cannache
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            17 months ago

            Organic plant based cement is already a possibility, yet we’re still using the good old mixes purely to avoid change

      • @burgersc12@sh.itjust.works
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        17 months ago

        I feel like this is closer to the truth. Isn’t there a theory that theres about a 2 decade lag between the CO2 (or equivalent) being released and the effects of heating?

    • Spzi
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      77 months ago

      IF we stop adding greenhouse gases to the air, the heating should stop.

      Unless we crossed a tipping point. If so, the heating could continue although we stopped.

    • @signor@lemmy.world
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      37 months ago

      So we can continue on with increasingly worse warming of the planet, OR we can follow the plot of snowpiercer.

    • Ben Matthews
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      37 months ago

      The atmosphere stores negligible heat (only weather, not climate), but the ocean has a much greater capacity than the atmosphere, for both heat and CO2 (mainly in the form of HCO3-), and it takes a long time (centuries - millenia) to fully mix the ocean. Also it takes ages for icecaps to melt. If you really stop adding CO2, concentration in the atmosphere will go down slowly as it mixes into deeper ocean, but not back to preindustrial, the surface temperature will likewise go down slowly and partially after a slight lag, but ice will keep melting (-> sea-level rises) for a while. Other gases and aerosols make short term response more complex.
      There’s no rule of thumb that summarises it, but I made an interactive model - here.