3 ms·

This is probably related to the (somewhat shortsightedly named) 4.2 kiloyear event when climate change and aridity caused the collapse of multiple long standing

• jolmg 7y ago
  I guess kiloyear is the new B.C. with the 2000 marking a new epoch. It really seems too shortsighted.
  • nostrademons 7y ago
    This comment thread sparked a new Wikipedia tangent for me: https://en.wikipedia.org/wiki/Before_Present https://en.wikipedia.org/wiki/Before_Present Apparently, the "before present" time scale is commonly used in archaeology and geology, and uses an epoch date of Jan 1, 1950. And there're two reasons for this: radiocarbon dating was first standardized in the 1950s, using a reference sample from 1950; and after the 1950s, widespread nuclear testing made radiocarbon dating inaccurate. It's actually less arbitrary and shortsighted than it seems. Future civilizations are going to face a discontinuity in the archaeological record, and it'll be roughly at the Before Present epoch date.
    • ako 7y ago
      Makes you think about the impact of nuclear testing... What else is impacted by these tests?
      • kuzehanka 7y ago
        Not a lot globally and at this timescale. Radionuclides is about it. Nuclear bombs put energy and radioactive particulates into the atmosphere. The effects of the radioactive particulates are fairly well understood. The amount of energy from even the largest bombs is negligible at those scales. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4165831/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4165831/
      • gdfasfklshg4 7y ago
        > Low-background steel is any steel produced prior to the detonation of the first nuclear bombs in the 1940s and 1950s. With the Trinity test and the nuclear bombings of Hiroshima and Nagasaki in 1945, and then subsequent nuclear weapons testing during the early years of the Cold War, background radiation levels increased across the world. Modern steel is contaminated with radionuclides because its production uses atmospheric air. Low-background steel is so-called because it does not suffer from such nuclear contamination. This steel is used in devices that require the highest sensitivity for detecting radionuclides. https://en.wikipedia.org/wiki/Low-background_steel https://en.wikipedia.org/wiki/Low-background_steel
        • dominicr 7y ago
          Apparently one source of low-background steel are ships built before 1945, especially military ships as they are large and can be in use for decades. The US navy has scraped a few old ships for this use and there are theories that some WW2 wrecks are being salvaged from the ocean bed for this purpose, but there is no conclusive evidence.
          • taejo 7y ago
            And not just before 1945: lead is used for radiation shielding, but freshly-mined lead is slightly radioactive itself... shipments of lead that were mined 2000 years ago and sitting at the bottom of the Mediterranean since then, much less so: https://www.nature.com/news/2010/100415/full/news.2010.186.html https://www.nature.com/news/2010/100415/full/news.2010.186.h...
  • njarboe 7y ago
    The zero year for the "Before Present(BP)" timescale is 1950. BP was used by carbon dating scientists first and 1950 was a nice round date a few years before the year when carbon dating[1] no longer worked due to atmospheric nuclear testing. [1]https://en.wikipedia.org/wiki/Radiocarbon_dating https://en.wikipedia.org/wiki/Radiocarbon_dating
  • dredmorbius 7y ago
    The number of different dates corresponding to "present" or "modern" is ... dizzying. https://en.wikipedia.org/wiki/Modernity https://en.wikipedia.org/wiki/Modernity See also "modern humans".
• agumonkey 7y ago
  Since collapse is getting trendy, we get a few articles and videos about previous occurrences. That said I'd be more interested in the aftermath and rebuild (recover/coma) period after that.
  • poelzi 7y ago
    I"m into that topic before it became mainstream, long term /r/collapse reader. To be honest, I don't think there will be a rebuild after this one. No water, no food and wet bulb temperatures over 35 °C for many hours a day, good look under this conditions. Maybe some smaller groups will find some sweat spot to survive in, but large scale civilizations I doubt that.
    • adwn 7y ago
      > To be honest, I don't think there will be a rebuild after this one. Wait, I'm confused. Are you claiming that current climate change will lead to the collapse of civilization?
      • cagenut 7y ago
        That is the default path we're on. All the models for things not going that way involve the emissions rate plummeting over the next decade and then going negative for several decades. Essentially the IPCC and scientists in general have baked in the assumption to the models that we are smart enough to avoid collapse by changing our behavior. TBD. Or to put it in P.G./HN jargon, (our current) civilization is "default dead" if we stay above 10Gt/year for the latter half of the century.
      • r3bl 7y ago
        He's far from being the first one to claim that. That's where doing nothing leads us, and so far, we (as in, the society) seem incapable of tackling this problem. It's already too late to stop it, and we seem incapable to contain it as well. For the overview of the argument, I'd recommend a paper called "Deep Adaptation: A Map for Navigating Climate Tragedy". Direct link: http://www.lifeworth.com/deepadaptation.pdf http://www.lifeworth.com/deepadaptation.pdf