<p>The average global warming due to greenhouse gases corresponds to a 33 Kelvin temperature increase.  If you remove all greenhouse gases the average global temperature would then decrease 33 Kelvin (from 288K to 255K).  </p>

<p>You might want to check out:
<a href="http://www.nasa.gov/topics/earth/features/co2-temperature.html" rel="nofollow">http://www.nasa.gov/topics/earth/features/co2-temperature.html</a>
 which estimates the CO<sub>2</sub> portion of global warming to be about 80%.</p>

<blockquote>
  <p>"... it is the 25 percent non-condensing greenhouse gas component, which includes carbon dioxide, that is the key factor in sustaining Earth’s greenhouse effect. By this accounting, carbon dioxide is responsible for 80 percent of the radiative forcing that sustains the Earth’s greenhouse effect."</p>
</blockquote>

<p>Simple math might suggest then that the average global temperature of Earth would be ~262K if CO<sub>2</sub> were completely removed.  There are always sources of CO<sub>2</sub> though, so you could never remove it all as it is constantly being replenished when animals breathe and things burn.</p>

CC BY-SA 3.0
2014-06-04T19:56:36.220Z
This answer mixes numbers from anthropogenic and total green house effect, thus the conclusion (262 K) seems to be wrong.
BHF
CC BY-SA 3.0
2014-06-04T23:05:49.450Z
I don't mention anything about anthropogenic portions... this is just total greenhouse effect.
f.thorpe
CC BY-SA 3.0
2014-06-05T17:12:28.687Z
The question mentions only CO₂.  There are other greenhouse gases such as water and CH₄.  80% is the proportion of the anthropogenic increased greenhouse effect due to CO₂.  Overall, water vapour is the most important greenhouse gas, so we could never cool it down to 262K simply by removing CO₂.  To answer this question properly requires a climate model, because feedbacks are complicated.
gerrit
CC BY-SA 3.0
2014-06-05T17:19:56.323Z
Perhaps you didn't read the link completely? It is not just the anthropogenic portion.  It says: "... it is the 25 percent non-condensing greenhouse gas component, which includes carbon dioxide, that is the key factor in sustaining Earth’s greenhouse effect. By this accounting, carbon dioxide is responsible for 80 percent of the radiative forcing that sustains the Earth’s greenhouse effect."  Yes water vapor is the most powerful GHG as a molecule... but it is not long lived and does not contribute to the greenhouse effect nearly as much as CO2.  IPCC radiative forcing charts confirm this.
f.thorpe
CC BY-SA 3.0
2014-06-03T20:23:44.093Z
2015-08-31T23:15:39.333Z
2015-08-31T23:15:39.333Z
f.thorpe
<p>So recently, scientists managed to <a href="http://www.rsc.org/chemistryworld/2014/05/solar-jet-fuel-made-out-thin-air" rel="nofollow">produce fuel basically out of thin air</a> (water, air and sunlight).</p>

<p>And in a discussion I had with a friend, the question came up, what would happen if you took that idea too far?</p>

<p>Say you could build an air-to-fuel plant large and efficient enough to take CO<sub>2</sub> out of the atmosphere faster than all the things we currently do to increase CO<sub>2</sub> levels add it in.</p>

<p>What would happen? First of all, how far could you realistically even take this: Would it be possible with the used process to go all the way down to 0 atmospheric CO<sub>2</sub> (or at least approach this arbitrarily closely)? And what effects would this have on the environment?</p>

<p>I immediately had three ideas that could happen but I wonder how realistic those would be:</p>

<ul>
<li>Average temperatures would drop (inverse Greenhouse effect) (but how far?)</li>
<li>Plants would eventually be unable to produce sugar through photosynthesis and die off</li>
<li>Instead of acidifying, oceans would become increasingly alkaline. Lime might drop out of the oceans rapidly which could, perhaps, have cancer-like effects on coral reefs and anything that heavily depends on lime.</li>
</ul>

<p>And besides those, are there any other obvious notable effects?</p>

CC BY-SA 3.0
2014-05-12T09:43:07.777Z
From a practical perspective, since this system would produce fuel from the CO2 it removed from the atmosphere, we'd just burn that fuel and release the CO2 again...
Semidiurnal Simon
CC BY-SA 3.0
2014-05-12T09:50:22.200Z
@SimonW of course. This technology has the potential to be a viable solution with which we might be able to stabilize atmospheric CO2 possibly indefinitely (plus minus the end of all life on Earth). That's not the point of the question though. I specifically asked what would happen if we overshot that goal, if we don't stabilize at, say, pre-industrial levels of CO2 but keep going.
kram1032
CC BY-SA 3.0
2014-05-12T14:58:13.737Z
fair enough ;-)
Semidiurnal Simon
CC BY-SA 3.0
2014-05-12T22:06:24.873Z
By extrapolation, reducing atmospheric CO2 levels to pre-industrial levels could have the effects you listed.  However, you do realize that at present, the thought of carbon sequestration succeeding to the point of undoing all industrial-era emissions is so hypothetical that it's not even funny?
200_success
CC BY-SA 3.0
2014-05-13T18:14:41.250Z
@200_success but what would happen if you go beyond pre-industrial levels? And I know that this is pretty darn hypothetical. As said, it came up in a discussion about that new technology. And going from a single bottle of air-made fuel to even just stabilizing current oil consumption is quite a long shot, obviously. I'm not oblivious in thinking that this will, in like five years, undo all damage that has been done. Obviously if that can happen at all, it'll take far longer than that. Again, though: That's not the point of the question.
kram1032
CC BY-SA 4.0
2020-08-20T04:49:07.710Z
This is question seems inspired by the French comic book/graphical novel Transperneige or the Korean movie based on it, Snowpiercer. It's rightwing wishfulfilment fantasy, utterly unreal, which seems to want to suggest that CO2 won't be a problem because, **someday soon,** we're gonna built this fantastic plant which will suck the CO2 right out of the air. Just so we don't have to give up our SUVs and wasting energy. There's however, another component to our present wasteful llifestyle: Peak Oil! If we suddenly run out oil without having alternatives, the societal effects will be devastating
GwenKillerby
CC BY-SA 4.0
2020-08-20T08:28:31.293Z
@GwenKillerby lol ok. No, I was merely interested. I do not have fantasies of this actually ever happening, and I haven't ever even heard of the sources you list.
kram1032
<climate><climate-change><hypothetical><co2>
What would happen if we could revert $\mathrm{CO}_2$ production but took it too far?
kram1032
# What would happen if we could revert $\mathrm{CO}_2$ production but took it too far?

(Asked by: username_0 on 2014-05-11)

So recently, scientists managed to [produce fuel basically out of thin air](http://www.rsc.org/chemistryworld/2014/05/solar-jet-fuel-made-out-thin-air) (water, air and sunlight).

And in a discussion I had with a friend, the question came up, what would happen if you took that idea too far?

Say you could build an air-to-fuel plant large and efficient enough to take CO2 out of the atmosphere faster than all the things we currently do to increase CO2 levels add it in.

What would happen? First of all, how far could you realistically even take this: Would it be possible with the used process to go all the way down to 0 atmospheric CO2 (or at least approach this arbitrarily closely)? And what effects would this have on the environment?

I immediately had three ideas that could happen but I wonder how realistic those would be:

* Average temperatures would drop (inverse Greenhouse effect) (but how far?)
* Plants would eventually be unable to produce sugar through photosynthesis and die off
* Instead of acidifying, oceans would become increasingly alkaline. Lime might drop out of the oceans rapidly which could, perhaps, have cancer-like effects on coral reefs and anything that heavily depends on lime.

And besides those, are there any other obvious notable effects?

**Tags:** climate, climate-change, hypothetical, co2

> **Comments:**
> **username_1**: From a practical perspective, since this system would produce fuel from the CO2 it removed from the atmosphere, we'd just burn that fuel and release the CO2 again...  
> **username_0**: @SimonW of course. This technology has the potential to be a viable solution with which we might be able to stabilize atmospheric CO2 possibly indefinitely (plus minus the end of all life on Earth). That's not the point of the question though. I specifically asked what would happen if we overshot that goal, if we don't stabilize at, say, pre-industrial levels of CO2 but keep going.  
> **username_1**: fair enough ;-)  
> **username_2**: By extrapolation, reducing atmospheric CO2 levels to pre-industrial levels could have the effects you listed.  However, you do realize that at present, the thought of carbon sequestration succeeding to the point of undoing all industrial-era emissions is so hypothetical that it's not even funny?  
> **username_0**: @username_2 but what would happen if you go beyond pre-industrial levels? And I know that this is pretty darn hypothetical. As said, it came up in a discussion about that new technology. And going from a single bottle of air-made fuel to even just stabilizing current oil consumption is quite a long shot, obviously. I'm not oblivious in thinking that this will, in like five years, undo all damage that has been done. Obviously if that can happen at all, it'll take far longer than that. Again, though: That's not the point of the question.  
> **username_3**: This is question seems inspired by the French comic book/graphical novel Transperneige or the Korean movie based on it, Snowpiercer. It's rightwing wishfulfilment fantasy, utterly unreal, which seems to want to suggest that CO2 won't be a problem because, **someday soon,** we're gonna built this fantastic plant which will suck the CO2 right out of the air. Just so we don't have to give up our SUVs and wasting energy. There's however, another component to our present wasteful llifestyle: Peak Oil! If we suddenly run out oil without having alternatives, the societal effects will be devastating  
> **username_0**: @username_3 lol ok. No, I was merely interested. I do not have fantasies of this actually ever happening, and I haven't ever even heard of the sources you list.  

---

## 1 answers

### Answer by username_4 on 2014-06-03. Score: 8 | Accepted answer

The average global warming due to greenhouse gases corresponds to a 33 Kelvin temperature increase. If you remove all greenhouse gases the average global temperature would then decrease 33 Kelvin (from 288K to 255K).

You might want to check out:
<http://www.nasa.gov/topics/earth/features/co2-temperature.html>
which estimates the CO2 portion of global warming to be about 80%.

> "... it is the 25 percent non-condensing greenhouse gas component, which includes carbon dioxide, that is the key factor in sustaining Earth’s greenhouse effect. By this accounting, carbon dioxide is responsible for 80 percent of the radiative forcing that sustains the Earth’s greenhouse effect."

Simple math might suggest then that the average global temperature of Earth would be ~262K if CO2 were completely removed. There are always sources of CO2 though, so you could never remove it all as it is constantly being replenished when animals breathe and things burn.

> **Comments:**
> **username_5**: This answer mixes numbers from anthropogenic and total green house effect, thus the conclusion (262 K) seems to be wrong.  
> **username_4**: I don't mention anything about anthropogenic portions... this is just total greenhouse effect.  
> **username_6**: The question mentions only CO₂.  There are other greenhouse gases such as water and CH₄.  80% is the proportion of the anthropogenic increased greenhouse effect due to CO₂.  Overall, water vapour is the most important greenhouse gas, so we could never cool it down to 262K simply by removing CO₂.  To answer this question properly requires a climate model, because feedbacks are complicated.  
> **username_4**: Perhaps you didn't read the link completely? It is not just the anthropogenic portion.  It says: "... it is the 25 percent non-condensing greenhouse gas component, which includes carbon dioxide, that is the key factor in sustaining Earth’s greenhouse effect. By this accounting, carbon dioxide is responsible for 80 percent of the radiative forcing that sustains the Earth’s greenhouse effect."  Yes water vapor is the most powerful GHG as a molecule... but it is not long lived and does not contribute to the greenhouse effect nearly as much as CO2.  IPCC radiative forcing charts confirm this.  

---

