4 ms·

there are no guarantees in life, can look up any random day and see a meteor streaking across the sky and realize that this is the end regardless of "sociopolit

there are no guarantees in life, can look up any random day and see a meteor streaking across the sky and realize that this is the end regardless of "sociopolitical structures". All that matters is sociotechnological progress to be able to progress further enough to overcome these tests of existence.

timschmidt 5mo ago
> look up any random day and see a meteor streaking across the sky That's happened rather more times in Earth's history than most folks are comfortable admitting. Tunguska would have leveled any major metropolitan city on the planet. I still think an impact is one of the more likely initiators of the Younger Dryas abrupt cooling and worldwide ~100M sealevel rise ~12,000 years ago. Conspicuously aligned with the oldest surviving traces of city living, agriculture, etc. It's increasingly accepted that a large portion of human history is 100M underwater on the continental shelves, estuaries, and other coastal areas where humans would have liked to live.
- vkou 5mo ago
  Sea level rise was much faster before the cooling of the Younger Dryas.
  - timschmidt 5mo ago
    You're right, and here's a graph: https://en.wikipedia.org/wiki/Past_sea_level#/media/File:Post-Glacial_Sea_Level.png https://en.wikipedia.org/wiki/Past_sea_level#/media/File:Pos... It's possible the sea level rise could have initiated the cooling. But there is much disagreement as to what exactly initiated the de-glaciation which caused the sealevel rise.
- mjhay 5mo ago
  The impact hypothesis for Younger Dryas isn’t really tenable. Among other things, the climate effects of a large bolide impact would be global, whereas Antarctica actually warmed during YD. This “Polar See-saw” pattern is easily explained by a northerly meltwater pulse hypothesis, but not a bolide.
- macartain 5mo ago
  It's increasingly accepted that a large portion of human history is 100M underwater on the continental shelves, estuaries, and other coastal areas where humans would have liked to live. Any references for that? Genuine question.
  - timschmidt 5mo ago
    Here's a review: https://www.sciencedirect.com/science/article/abs/pii/S0277379108001911 https://www.sciencedirect.com/science/article/abs/pii/S02773... More: https://www.pnas.org/doi/10.1073/pnas.1411762111 https://www.pnas.org/doi/10.1073/pnas.1411762111 https://www.nature.com/articles/s41586-025-08769-7 https://www.nature.com/articles/s41586-025-08769-7 https://www.academia.edu/9737879/Land_Beneath_the_Waves_Submerged_landscapes_and_sea_level_change_A_joint_geoscience_humanities_strategy_for_European_Continental_Shelf_Prehistoric_Research https://www.academia.edu/9737879/Land_Beneath_the_Waves_Subm... https://pure.york.ac.uk/portal/en/publications/under-the-sea-archaeology-and-palaeolandscapes-of-the-continental https://pure.york.ac.uk/portal/en/publications/under-the-sea...
    - macartain 5mo ago
      Much appreciated - living in the UK, I have heard of Doggerland and should have expected there would be plenty of similar areas worldwide - this is interesting stuff.
      - timschmidt 5mo ago
        It's really amazing how much more connected the world was not very long ago. Take a look at 24k years ago here: https://sea-level.vercel.app/ https://sea-level.vercel.app/ Nearly every continent is one connected landmass. And all the most prime real estate is now under water.

timschmidt 5mo ago

> look up any random day and see a meteor streaking across the sky That's happened rather more times in Earth's history than most folks are comfortable admitting. Tunguska would have leveled any major metropolitan city on the planet. I still think an impact is one of the more likely initiators of the Younger Dryas abrupt cooling and worldwide ~100M sealevel rise ~12,000 years ago. Conspicuously aligned with the oldest surviving traces of city living, agriculture, etc. It's increasingly accepted that a large portion of human history is 100M underwater on the continental shelves, estuaries, and other coastal areas where humans would have liked to live.

vkou 5mo ago
Sea level rise was much faster before the cooling of the Younger Dryas.
- timschmidt 5mo ago
  You're right, and here's a graph: https://en.wikipedia.org/wiki/Past_sea_level#/media/File:Post-Glacial_Sea_Level.png https://en.wikipedia.org/wiki/Past_sea_level#/media/File:Pos... It's possible the sea level rise could have initiated the cooling. But there is much disagreement as to what exactly initiated the de-glaciation which caused the sealevel rise.
mjhay 5mo ago
The impact hypothesis for Younger Dryas isn’t really tenable. Among other things, the climate effects of a large bolide impact would be global, whereas Antarctica actually warmed during YD. This “Polar See-saw” pattern is easily explained by a northerly meltwater pulse hypothesis, but not a bolide.
macartain 5mo ago
It's increasingly accepted that a large portion of human history is 100M underwater on the continental shelves, estuaries, and other coastal areas where humans would have liked to live. Any references for that? Genuine question.
- timschmidt 5mo ago
  Here's a review: https://www.sciencedirect.com/science/article/abs/pii/S0277379108001911 https://www.sciencedirect.com/science/article/abs/pii/S02773... More: https://www.pnas.org/doi/10.1073/pnas.1411762111 https://www.pnas.org/doi/10.1073/pnas.1411762111 https://www.nature.com/articles/s41586-025-08769-7 https://www.nature.com/articles/s41586-025-08769-7 https://www.academia.edu/9737879/Land_Beneath_the_Waves_Submerged_landscapes_and_sea_level_change_A_joint_geoscience_humanities_strategy_for_European_Continental_Shelf_Prehistoric_Research https://www.academia.edu/9737879/Land_Beneath_the_Waves_Subm... https://pure.york.ac.uk/portal/en/publications/under-the-sea-archaeology-and-palaeolandscapes-of-the-continental https://pure.york.ac.uk/portal/en/publications/under-the-sea...
  - macartain 5mo ago
    Much appreciated - living in the UK, I have heard of Doggerland and should have expected there would be plenty of similar areas worldwide - this is interesting stuff.
    - timschmidt 5mo ago
      It's really amazing how much more connected the world was not very long ago. Take a look at 24k years ago here: https://sea-level.vercel.app/ https://sea-level.vercel.app/ Nearly every continent is one connected landmass. And all the most prime real estate is now under water.