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Global heating caused by carbon in atmosphere => melting permafrost => releasing more carbon stored in permafrost => even more heating of globe. Even if it is

Global heating caused by carbon in atmosphere => melting permafrost => releasing more carbon stored in permafrost => even more heating of globe. Even if it is S-curve I do not sure lots of people can survive Venus' climate.

dmarchand90 4y ago
Are you sure it's going to be like Venus? Didn't all the carbon used to be in the atmosphere in earlier points in history?
criddell 4y ago
Even the worst case predictions don't result in Venus-like temperatures, do they?
- jandrese 4y ago
  No, but what if we got half way to Venus-like temperatures and only made it to 200C? In reality, the planet will stall out around 100C due to all of the water that needs to boil off and the huge steam clouds that would then increase the planet's albedo (but also trap heat). That's probably the top of the S-curve for the lifetime of mankind. Having the solar rays split that water and let the hydrogen escape to make an actual Venus like atmosphere is a more geological timescale process.
  - criddell 4y ago
    When I google for "worst case global warming", I'm not finding anything like 100C. More like +5C. Here's one link I followed: https://www.science.org/content/article/after-40-years-researchers-finally-see-earths-climate-destiny-more-clearly https://www.science.org/content/article/after-40-years-resea...
    - jandrese 4y ago
      While I was exaggerating somewhat in my original post, I should point out that most climate change papers stop around +7C or so because after that it's assumed most everyone is dead and the models won't be valid anymore. Plus, there won't be anybody around to care.
  - thehappypm 4y ago
    This argument is hysterical and counterproductive.
ben_w 4y ago
Even the conversion of all known organic carbon [0] on Earth into CO2 isn't going to be close to Venus. Sun expanding over the next billion years might just about do that, unless the water vapour dissociates and the hydrogen escapes, but that's about the only way we get even close to Venusian conditions, IIRC. [0] as in, the biomass and all of the fossil fuel reserves; I'm not including carbonate rocks, though it looks like including inorganic minerals still wouldn't be Venusian even though it would be far enough from today that it might as well be as far as "life" was concerned.
jstanley 4y ago
How do you explain the presence of carbon in permafrost? For the concentration of carbon in permafrost to exceed the present concentration of carbon in the atmosphere, wouldn't the concentration of carbon in the atmosphere at the time the permafrost was initialy frozen have had to exceed the current concentration of carbon in the atmosphere? Which would imply that the current level of carbon in the atmosphere is not the cause of the increased temperature?
- modo_mario 4y ago
  >For the concentration of carbon in permafrost to exceed the present concentration of carbon in the atmosphere, wouldn't the concentration of carbon in the atmosphere at the time the permafrost was initialy frozen have had to exceed the current concentration of carbon in the atmosphere? Do you think permafrost is giant bubbles of air that got trapped in frost or something? Your comment baffles me somewhat. What do you think of the concentration of carbon in our current atmosphere when you see a rotting log?
- olddustytrail 4y ago
  CO2 levels were higher in the past, but the sun was dimmer. Edit: hey dang. I now delete the last sentence of most of my posts. Thanks for the advice!

dmarchand90 4y ago

Are you sure it's going to be like Venus? Didn't all the carbon used to be in the atmosphere in earlier points in history?

criddell 4y ago

Even the worst case predictions don't result in Venus-like temperatures, do they?

jandrese 4y ago
No, but what if we got half way to Venus-like temperatures and only made it to 200C? In reality, the planet will stall out around 100C due to all of the water that needs to boil off and the huge steam clouds that would then increase the planet's albedo (but also trap heat). That's probably the top of the S-curve for the lifetime of mankind. Having the solar rays split that water and let the hydrogen escape to make an actual Venus like atmosphere is a more geological timescale process.
- criddell 4y ago
  When I google for "worst case global warming", I'm not finding anything like 100C. More like +5C. Here's one link I followed: https://www.science.org/content/article/after-40-years-researchers-finally-see-earths-climate-destiny-more-clearly https://www.science.org/content/article/after-40-years-resea...
  - jandrese 4y ago
    While I was exaggerating somewhat in my original post, I should point out that most climate change papers stop around +7C or so because after that it's assumed most everyone is dead and the models won't be valid anymore. Plus, there won't be anybody around to care.
- thehappypm 4y ago
  This argument is hysterical and counterproductive.

ben_w 4y ago

Even the conversion of all known organic carbon [0] on Earth into CO2 isn't going to be close to Venus. Sun expanding over the next billion years might just about do that, unless the water vapour dissociates and the hydrogen escapes, but that's about the only way we get even close to Venusian conditions, IIRC. [0] as in, the biomass and all of the fossil fuel reserves; I'm not including carbonate rocks, though it looks like including inorganic minerals still wouldn't be Venusian even though it would be far enough from today that it might as well be as far as "life" was concerned.

jstanley 4y ago

How do you explain the presence of carbon in permafrost? For the concentration of carbon in permafrost to exceed the present concentration of carbon in the atmosphere, wouldn't the concentration of carbon in the atmosphere at the time the permafrost was initialy frozen have had to exceed the current concentration of carbon in the atmosphere? Which would imply that the current level of carbon in the atmosphere is not the cause of the increased temperature?

modo_mario 4y ago
>For the concentration of carbon in permafrost to exceed the present concentration of carbon in the atmosphere, wouldn't the concentration of carbon in the atmosphere at the time the permafrost was initialy frozen have had to exceed the current concentration of carbon in the atmosphere? Do you think permafrost is giant bubbles of air that got trapped in frost or something? Your comment baffles me somewhat. What do you think of the concentration of carbon in our current atmosphere when you see a rotting log?
olddustytrail 4y ago
CO2 levels were higher in the past, but the sun was dimmer. Edit: hey dang. I now delete the last sentence of most of my posts. Thanks for the advice!