5 ms·

Probably easier than you think, just add a few more ATM of CO2 and it will work out to be just like Venus. Though -- it's actually a lot of CO2, for starters b

Probably easier than you think, just add a few more ATM of CO2 and it will work out to be just like Venus. Though -- it's actually a lot of CO2, for starters burning absolute every last bit of fossil fuel would probably contribute to ~0.1% of the amount needed for a runaway greenhouse event.

gshubert17 6y ago
Burning all the fossil fuel reserves we have (know about), would add over 200 ppm CO2 to the atmosphere (mostly from 1 trillion tons of coal). The additions from oil and gas are smaller. We'd then have over 500 ppm CO2. "Recoverable" coal is about 20 times proven reserves, so burning all that would add 4000 ppm CO2. Now the total would be 4500 ppm CO2, or almost 0.5 percent! Likely to be quite unhealthy. https://knoema.com/infographics/smsfgud/bp-world-reserves-of-fossil-fuels https://knoema.com/infographics/smsfgud/bp-world-reserves-of... https://inspectapedia.com/hazmat/Carbon_Dioxide_Hazards.php https://inspectapedia.com/hazmat/Carbon_Dioxide_Hazards.php
- djrogers 6y ago
  All the while you’re doing that, plant life would be booming, and after a sufficient period of time would capture enough of that CO2 again to make it possible for non-plant life to once again flourish.
  - sbierwagen 6y ago
    "A sufficient period of time" is underselling it a little. Coal is only formed if wood is buried without rotting first. If we burned all the coal we can find, it would take tens of millions of years to be replaced.
    - perl4ever 6y ago
      I had a vague impression that the processes that produced fossil fuels would probably not renew in due time, because the existing layers have something to do with the inability of microbes to break down lignin long ago. Once the capability evolved, the same process can't repeat even if one waits a long time?
      - jacobr1 6y ago
        This paper has an interesting take on the history: https://www.pnas.org/content/113/9/2442 https://www.pnas.org/content/113/9/2442
Ekaros 6y ago
I have been wondering about that. Hasn't all of the carbon now in fossil-fuels been in atmosphere at some point? Or has more of it been freed from earth's crust or arrived as meteors since formation of the fossil-fuels? So in the end wouldn't worst case scenario be of around time when they formed?
- thgaway17 6y ago
  Shhh. Some of us are trying to make a living selling green energy.
- sudhirj 6y ago
  This seems to be a weird misconception about climate change, that the earth getting hotter will somehow end all life. That’s very doubtful. All the plants will love the new greenhouse, lots of energy in the atmosphere, rain every day, the whole planet a tropical paradise. It’s the humans and some other species who’ll be heavily inconvenienced. Solving climate change is mostly so we can stay comfortable and not have to deal with more ecological crises and refugees.
  - jbay808 6y ago
    Not necessarily a tropical paradise, if it goes the way of the end-permian mass extinction: http://burro.case.edu/Academics/USNA229/impactfromthedeep.pdf http://burro.case.edu/Academics/USNA229/impactfromthedeep.pd...
  - guenthert 6y ago
    Only if it get just a little warmer. Photosynthesis is temperature dependent however and its maximum is at a modest 20 degree C, above 40 degree C its efficiency falls rapidly [1]. If it gets much warmer than that, and a run-away greenhouse effect would ensure that, only algae and some bacteria survive a while longer. Once the oceans are boiling, it's hard to imagine any life surviving though. There doesn't seem consensus on whether Earth could truly reach a runaway greenhouse state or would rather just settle at a higher temperature. In any case, only the ecological (and consequently economic) crises and refugees problem are the ones currently living people will be affected by, but that ought to be enough to take action. [1] https://sciencing.com/effect-temperature-rate-photosynthesis-19595.html https://sciencing.com/effect-temperature-rate-photosynthesis...
dnautics 6y ago
You do understand that even burning all of the oxygen in the atmosphere currently to produce CO2 would yield less than an ATM
- rriepe 6y ago
  Only 70 more though and you're right there at Venus' pressure.
- perl4ever 6y ago
  Well, presumably something happened on Venus to convert large amounts of carbonate rocks to CO2? How would we rule out the possibility of that happening here?
- Aperocky 6y ago
  Yes. That's why someone need to break down all the carbonate rocks and release all the CO2, that will probably work out to a few more ATM.. Easier said than done.
vaduz 6y ago
We would do better with methane (100-year GWP 25), or even better with nitrous oxide - with added bonus that both N2 and O2 to produce it can be taken straight out of atmosphere (100-year GWP 298), though they would not last very long.
nikanj 6y ago
Venus is ~100 million kilometers from the sun, Earth about 150 million km. No matter of greenhouse gases is going to compensate for that difference in radiation heating. Because radiation dissipates to the distance squared, we get around 40-50% of the heating Venus does.
- perl4ever 6y ago
  You may be right in your conclusion, but your logic seems like it would imply Venus can't be hotter than Mercury, either?

gshubert17 6y ago

Burning all the fossil fuel reserves we have (know about), would add over 200 ppm CO2 to the atmosphere (mostly from 1 trillion tons of coal). The additions from oil and gas are smaller. We'd then have over 500 ppm CO2. "Recoverable" coal is about 20 times proven reserves, so burning all that would add 4000 ppm CO2. Now the total would be 4500 ppm CO2, or almost 0.5 percent! Likely to be quite unhealthy. https://knoema.com/infographics/smsfgud/bp-world-reserves-of-fossil-fuels https://knoema.com/infographics/smsfgud/bp-world-reserves-of... https://inspectapedia.com/hazmat/Carbon_Dioxide_Hazards.php https://inspectapedia.com/hazmat/Carbon_Dioxide_Hazards.php

djrogers 6y ago
All the while you’re doing that, plant life would be booming, and after a sufficient period of time would capture enough of that CO2 again to make it possible for non-plant life to once again flourish.
- sbierwagen 6y ago
  "A sufficient period of time" is underselling it a little. Coal is only formed if wood is buried without rotting first. If we burned all the coal we can find, it would take tens of millions of years to be replaced.
  - perl4ever 6y ago
    I had a vague impression that the processes that produced fossil fuels would probably not renew in due time, because the existing layers have something to do with the inability of microbes to break down lignin long ago. Once the capability evolved, the same process can't repeat even if one waits a long time?
    - jacobr1 6y ago
      This paper has an interesting take on the history: https://www.pnas.org/content/113/9/2442 https://www.pnas.org/content/113/9/2442

Ekaros 6y ago

I have been wondering about that. Hasn't all of the carbon now in fossil-fuels been in atmosphere at some point? Or has more of it been freed from earth's crust or arrived as meteors since formation of the fossil-fuels? So in the end wouldn't worst case scenario be of around time when they formed?

thgaway17 6y ago
Shhh. Some of us are trying to make a living selling green energy.
sudhirj 6y ago
This seems to be a weird misconception about climate change, that the earth getting hotter will somehow end all life. That’s very doubtful. All the plants will love the new greenhouse, lots of energy in the atmosphere, rain every day, the whole planet a tropical paradise. It’s the humans and some other species who’ll be heavily inconvenienced. Solving climate change is mostly so we can stay comfortable and not have to deal with more ecological crises and refugees.
- jbay808 6y ago
  Not necessarily a tropical paradise, if it goes the way of the end-permian mass extinction: http://burro.case.edu/Academics/USNA229/impactfromthedeep.pdf http://burro.case.edu/Academics/USNA229/impactfromthedeep.pd...
- guenthert 6y ago
  Only if it get just a little warmer. Photosynthesis is temperature dependent however and its maximum is at a modest 20 degree C, above 40 degree C its efficiency falls rapidly [1]. If it gets much warmer than that, and a run-away greenhouse effect would ensure that, only algae and some bacteria survive a while longer. Once the oceans are boiling, it's hard to imagine any life surviving though. There doesn't seem consensus on whether Earth could truly reach a runaway greenhouse state or would rather just settle at a higher temperature. In any case, only the ecological (and consequently economic) crises and refugees problem are the ones currently living people will be affected by, but that ought to be enough to take action. [1] https://sciencing.com/effect-temperature-rate-photosynthesis-19595.html https://sciencing.com/effect-temperature-rate-photosynthesis...

dnautics 6y ago

You do understand that even burning all of the oxygen in the atmosphere currently to produce CO2 would yield less than an ATM

rriepe 6y ago
Only 70 more though and you're right there at Venus' pressure.
perl4ever 6y ago
Well, presumably something happened on Venus to convert large amounts of carbonate rocks to CO2? How would we rule out the possibility of that happening here?
Aperocky 6y ago
Yes. That's why someone need to break down all the carbonate rocks and release all the CO2, that will probably work out to a few more ATM.. Easier said than done.

vaduz 6y ago

We would do better with methane (100-year GWP 25), or even better with nitrous oxide - with added bonus that both N2 and O2 to produce it can be taken straight out of atmosphere (100-year GWP 298), though they would not last very long.

nikanj 6y ago

Venus is ~100 million kilometers from the sun, Earth about 150 million km. No matter of greenhouse gases is going to compensate for that difference in radiation heating. Because radiation dissipates to the distance squared, we get around 40-50% of the heating Venus does.

perl4ever 6y ago
You may be right in your conclusion, but your logic seems like it would imply Venus can't be hotter than Mercury, either?