• fearout
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    11 months ago

    Let me put it this way. The difference in average global temperature between the last ice age 100,000 years ago and pre-industrial earth around 100 years ago is just ~3.5C. The expected temperature rise due to recent climate change is about +3C.

    A lot is going to happen, and much sooner than in 50 years.

    With current trends, it looks like we’re heading towards severe climate destabilization, much more common extreme weather events, some parts of the world becoming uninhabitable for humans, lots of mass extinction events for many species, including those that humanity currently relies upon, and probable global famine.

    The fact that it’s not a complete extinction doesn’t make it fine. Sure, Earth as a planet will be fine. But the civilisation has some really hard challenges coming up, and it’s currently not prepared for them.

    • @tallwookie@lemmy.world
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      211 months ago

      it’s true that some changes are coming down the pipeline, I just dont see those changes having any noticeable effect in the next ~50 years.

      if it took 250 years for the climate to warm up (since the dawn of the industrial revolution), then it’s going to take just as long to cool down - and that’s presuming that we have the ability to make changes in our power generation methods to eliminate our dependence on coal/oil. a bit over 60% of all electricity generation, globally, comes from Coal, Gas, and Oil (in that order). we really just need reliable fusion & enough fuel for a few decades - by then the technology will have matured enough where we can get H3 from space. tangential to that would be to base solar power generation in a L4 or L5 orbit, then beam the power back to the surface.

      in regards to extinction/famine - the absolute maximum carrying capacity of Earth, in regards to our species, is somewhere between 9 and 10 billion. that’s a hard limit, unless we’re willing to live hand to mouth like some people do in the 3rd world (very few folks are going to sign up for that). we’re at 8 billion or so now. people arent going to stop having kids unless they’re forced to, or there’s not enough food to feed them (though as recent decades in Africa have shown, usually not even then). at some point, famine on a massive scale is a nigh certain thing. perhaps we need to depopulate by 30% or so? I’m not a policy maker and neither is anyone on Lemmy, so it probably doesnt matter that much what we think.

      • fearout
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        1111 months ago

        It didn’t really take 250 years though, early emissions were almost negligible. Most of it started like 60 years ago. You’re right that we’re not stopping it anytime soon, but the effective timelines are shorter than centuries.

        Also, what’s your reasoning/source on a 10 bn “absolute” cap? It might be a cap while using modern farming, technologies and logistics, but it’s not absolute by any means. You mention beaming energy from space, then why not mention Eucomenopolis concepts that allow for trillions of people to inhabit Earth? :) Or simply once you have fusion, you can have vertical farms and Arcologies that can sustain a much larger population.

        The issue isn’t that it’s impossible, rather that we’re not gonna develop any of this tech before humanity faces existential problems in many parts of the world.

        Also, it’s weird that you got from “this temperature variance is minimal” and “this average is on the low side of comfortable” to “let’s get rid of 30% of population then”. o_O

        • @tallwookie@lemmy.world
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          111 months ago

          oh there are many different solutions, i just mentioned a few of the more realistic ones. materials science will need to improve by several magnitudes before true arcologies are possible. but yes, it’s unlikely that we’ll develop the tech we need in the timeframe.

          carrying capacity? i looked into it several years ago after reading about it somewhere. probably sci-fi, I do enjoy those. on the low end, it’s around 2 billion. an 80% population drop may be required. there will be resource wars before that happens though & quite likely a few exchanges of strategic nuclear weapons. presumably the famines would drastically increase after that? I supose we’ll see.