# Has science determined an optimum CO2 level? **URL:** \ **Category:** Factual Questions\ **Created:** [November 24, 2014, 8:48pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520 "2014-11-24T20:48:01Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Learjeff](https://avatars.discourse-cdn.com/v4/letter/l/94ad74/32.png) [@Learjeff](https://boards.straightdope.com/u/Learjeff)\ **Post date:** [November 26, 2014, 2:17am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/21 "2014-11-26T02:17:52Z")
> [@Smeghead](#): > > Optimized for what? That is exactly the question. The simplest answer is “whatever it’s been during most of the history of civilization, because that’s what agriculture is optimized to.” That’s an oversimplified answer, of course, but to get any more specific, well, re-read Colibri’s post above. “Change causes upset.” Think about that. Even change for the better causes problems. Economies, population centers, and agriculture are all optimized for current conditions. Changing conditions rapidly would be a disaster. > [@EdwinAmi](#): > > the entire idea of thinking of the relationship as being “CO2 = more warmth” is overly simplistic. The earth, being a stable complex system, There’s lots of evidence that it’s not a very stable system. Iceball Earth, for example. > [@scr4](#): > > Nobody is ignoring negative feedback. I think you’re misunderstanding what it is, though. Negative feedback is not something that pushes a system back to the same original. If you change a parameter of a system, negative feedback causes the system to settle at a _new, different_ equilibrium, which may be very different from the original condition. > > Think of a basket hanging from a spring. If you add a weight to the basket, the basket starts moving down, and the spring will extend. But the more the spring extends, the more upward force it exerts on the basket. That’s negative feedback, and this prevents the basket from falling all the way to the floor. But the spring does not bring the basket back to the original height. The basket comes to a stop at a lower point. Nice example, thanks! ---
**Author:** ![clairobscur](https://avatars.discourse-cdn.com/v4/letter/c/839c29/32.png) [@clairobscur](https://boards.straightdope.com/u/clairobscur)\ **Post date:** [November 26, 2014, 4:42am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/22 "2014-11-26T04:42:56Z")
> [@EdwinAmi](#): > > and make other areas much more fertile/useful Probably right. So for instance American middle-west farmers will just have to relocate to Siberia. Problem solved. ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [November 26, 2014, 8:13am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/23 "2014-11-26T08:13:54Z")
> [@EdwinAmi](#): > > Just the change in insolation from winter to summer is enourmous when you count the huge surface areas involved, and that it happens in less than a year. I am not understanding. Are you saying the Earth get a different amount of sun in the winter than it does in the summer? Is the summer solstice in June or December? ---
**Author:** ![septimus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/septimus/32/410_2.png) [@septimus](https://boards.straightdope.com/u/septimus)\ **Post date:** [November 26, 2014, 9:55am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/24 "2014-11-26T09:55:12Z")
> [@EdwinAmi](#): > > … Can the sum of all human activity even remotely compare to all the plants in the world? … The biosphere releases almost exactly as much carbon to the atmosphere as it extracts. This is due to a balance between photosynthesizing plants and respirers (animals etc.). One way to understand the recent spurt in atmospheric CO[sub]2[/sub] is to compare the millions of years over which fossil fuels accumulated with the short span of their burning. > [@EdwinAmi](#): > > That seems silly, given that all the forces on the earth are enormous and in the absence of negative-feedback systems we know would produce huge rapid changes. Indeed, they DO produce them, but they’re countered by negative feedback. > > … To ignore negative feedback mechanisms is to ignore that the climate is stable,… Examine the [Earth’s temperature](http://www.buildart.com/images/Images2011/TIMELINE_FULL.jpg) or [temperature compared with CO[sub]2[/sub] levels](http://astronomy.nmsu.edu/tharriso/ast110/carbondioxide.gif) over 100’s of million years and see that the Earth’s climate is _NOT_ stable over long periods of time. I don’t know how well the drivers of transitions are understood, but we could be at a transition now. There are both positive and negative feedback mechanisms at work. One negative feedback which kept temperature within a narrow band during the Quaternary is that melting ice leads to oceanic CO[sub]2[/sub] accumulation, reducing the greenhouse effect. Ice, already at a low level for the Quaternary, continues to melt, but the resultant equilibrium may have higher temperatures and more acidic oceans. > [@EdwinAmi](#): > > and make other areas much more fertile/useful 😕 Which is it? Climate change isn’t happening … or climate change is good? ---
**Author:** ![Budget\_Player\_Cadet](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/budget_player_cadet/32/205_2.png) [@Budget\_Player\_Cadet](https://boards.straightdope.com/u/Budget_Player_Cadet)\ **Post date:** [November 26, 2014, 10:17am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/25 "2014-11-26T10:17:42Z")
> [@Colibri](#): > > The problem with rising CO2 and associated climate changes isn’t so much what levels they eventually reach, but their speed. We can no doubt adapt to higher CO2 levels and to climate changes; the problem is that they will make some areas that we now use unsuitable, and there will be enormous costs and disruptions in moving them to new areas that are suitable. Likewise with plants and animals. Given enough time they will adapt to changing climate. However, changes are likely to come too rapidly for plants and animals to shift their ranges in time or to adapt physiologically. We have a winner. > [@EdwinAmi](#): > > the entire idea of thinking of the relationship as being “CO2 = more warmth” is overly simplistic. The earth, being a stable complex system, has negative-feedback systems, as this is the only way such complex systems can exist without going haywire. This is not really accepted in the global-warming model, but will come to be known as correct within the next hundred years as science advances and understands more about this obscure part of science You know what I noticed here? Not a single citation. I mean, you make a lot of very tall claims, but you completely fail to back any of them up. Is this like your claims about solar power again? > [@](#): > > The forces that are at work on earth are massive. The only way this planet could still be existing without its atmosphere being blown off or all the water boiled off or whatever is if all the huge forces were balanced by negative-feedback systems. > > So whatever happens, it will all be balanced out in some way. There would be trade offs depending on the region, but overall there could not be huge catastrophic effects, if by that you mean insane weather that’s unprecedented in Earth’s history Right. Which is why the climate never changes. Ever. It’s why the earth was not ever covered in ice, and when it was, it snapped back almost immediately. It’s why the eocene thermal maximum never happened. It’s why every time something happens that would affect the earth’s climate, negative feedbacks immediately change it back. … …Sounds kinda stupid when you say it like that, right? That’s because it’s _wrong_. It’s blatantly and obviously wrong. Yeah, there are negative feedbacks. But they are neither instant, nor bottomless. And there’s good evidence for positive feedbacks as well, and good reason to believe that some negative feedbacks (such as the ocean) are losing their ability to function as negative feedbacks as we get warmer. > [@EdwinAmi](#): > > The feedback mechanisms that we know exist are based on the levels of different things, not their rate of change. **The higher the CO2, or anything, the more a negative feedback kicks in.** Citation needed. > [@](#): > > I mean, think about it, both the oceans and the plants can absorb CO2. Can the sum of all human activity even remotely compare to all the plants in the world? The endless forests in Siberia, the still huge Amazon, the endless grasslands of Africa, all of which are dwarfed by ocean algae? Of course not. Citation needed. > [@](#): > > Even a marginal change in their growth rate would dwarf human output of CO2. Ditto the enormous oceans. Citation needed. > [@](#): > > To ignore negative feedback mechanisms is to ignore that the climate is stable, that there is even a climate at all, instead of a violent fucking constant windstorm and massive temperature swing a la venus or whichever planet it is. Citation needed that we’re ignoring it. Everything you’re saying is wrong and you make absolutely no attempt to back it up with published research (because you can’t, _because it’s wrong_), appealing rather to our common sense. Just like it’s common sense that volcanoes must dwarf human CO2 output (wrong), that we couldn’t possibly affect the carbon cycle (wrong), that such a tiny portion of the atmosphere could not have a huge effect (wrong), and that climate has changed in the past, therefore we couldn’t be the cause of the current change ([wrong wrong wrong wrong wrong](http://angryscience.yougetwhatyouwant.org/but-its-been-warmer-in-the-past/)). Stop appealing to common sense, and actually do some research. Your insistence that your assumptions about the natural world must be true is the reason that _every single thing you’ve said about AGW in this thread is **wrong** _. > [@EdwinAmi](#): > > and make other areas much more fertile/useful Yeah! Which is really helpful when we completely lack the architecture in place to take advantage of it! To come back to **Colibri** ’s (completely accurate) point: modern human society is built around the climate that has existed for the past few centuries. Our cities are built at the sea because that’s how shipping used to work - if the sea level rises or drops significantly, their position becomes precarious or useless. Our farms and agriculture is centered around crops we know can grow well in the environments that are good for growing - if these environments become arid, there’s little guarantee that the new areas will not pose significant problems. Our entire agricultural supply line (and believe me, this shit is really, really, _really_ non-trivial in magnitude and cost to relocate/rebuild) is based around things like the grain belt - if we can’t grow there any more, we’ll have to move all of this around, and it’s going to be some really lean years until we pull it off. Our population centers are often built around aquifers or rivers that run off from glaciers - if rising temperatures make these water supplies unsustainable, we will face migration and refugees. Our entire modern society is based around the climate we live in. The problem is not “we’re away from the ideal CO2 concentration”, the problem is “the change in CO2 concentration leads to the infrastructure we’ve built over centuries needing to adapt faster than is comfortable for us”. And that’s ignoring the rest of nature, which doesn’t quite have the same tools we do to adapt to changes. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [November 26, 2014, 3:38pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/26 "2014-11-26T15:38:54Z")
> [@EdwinAmi](#): > > and make other areas much more fertile/useful In what proportion? As has been said, even if some areas become better there would still be enormous costs involved in developing new infrastructure. If the best area for corn cultivation moves from the Midwest to Canada, you then have to build new roads, railroads, silos, and everything else to support it. Meanwhile much of the existing infrastructure for corn cultivation in the Midwest may not be suitable for sugar cane, or whatever the new crop is. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [November 26, 2014, 3:38pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/27 "2014-11-26T15:38:48Z")
> [@EdwinAmi](#): > > and make other areas much more fertile/useful In what proportion? As has been said, even if some areas become better there would still be enormous costs involved in developing new infrastructure. If the best area for corn cultivation moves from the Midwest to Canada, you then have to build new roads, railroads, silos, and everything else to support it. Meanwhile much of the existing infrastructure for corn cultivation in the Midwest may not be suitable for sugar cane, or whatever the new crop is. ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [November 26, 2014, 3:47pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/28 "2014-11-26T15:47:17Z")
Or if you assume the oceans to be a massive, inexhaustible sink for CO[sub]2[/sub], then what about the resulting acidification? CO[sub]2[/sub] + water --\> Carbonic Acid (H[sub]2[/sub]CO[sub]3[/sub]) ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [November 26, 2014, 4:51pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/29 "2014-11-26T16:51:07Z")
IMO, the possible shift of agriculture from the US to Canada isn’t as troubling as, say, loss of agriculture from [large parts of southern Africa and southern Asia](http://www.sciencemag.org/content/319/5863/607). There is a fairly developed infrastructure in Canada, and the government is stable and prosperous enough to allow efficient development further to the north. On the other hand, the Siberian steppes are vast and almost completely undeveloped. Somehow I doubt that a billion subsistence farmers from Africa and other parts of Asia can just pack up and start farming in the [newly thawed permafrost](http://iopscience.iop.org/1748-9326/6/4/045207/fulltext/) in Siberia… ---
**Author:** ![Budget\_Player\_Cadet](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/budget_player_cadet/32/205_2.png) [@Budget\_Player\_Cadet](https://boards.straightdope.com/u/Budget_Player_Cadet)\ **Post date:** [November 26, 2014, 6:18pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/30 "2014-11-26T18:18:04Z")
Plus, on a somewhat tangential note, it doesn’t help that the people currently in charge in Russia are very strongly against agricultural technology. ---
**Author:** ![EdwinAmi](https://avatars.discourse-cdn.com/v4/letter/e/5fc32e/32.png) [@EdwinAmi](https://boards.straightdope.com/u/EdwinAmi)\ **Post date:** [November 27, 2014, 5:23am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/31 "2014-11-27T05:23:33Z")
You guys are saying that climate science isn’t ignoring it, but one of the guys above JUST SAID that there are positive feedback mechanisms before the negative, or something like that > [@](#): > > this is completely wrong and ignores all scientific experiment and investigation Oh yeah, right, that experiment where they built a time machine and slowly tracked all climate data for the past 1,000,000+ years Oh right… Oh, but stupid tree rings are just as good as that, right? Other kinds of science can only make claims they can actually experiment on, with exact precise data whose tiny variance is only allowed to be caused by imperfect measurement machines. Every single interaction in physics and chemistry and electronics can be explained exactly by the relevant theories, and reproduced 100%. But climatologists get to look at some tree rings and I’m supposed to buy it 100%, and impoverish my entire country. That level of faith? > [@](#): > > The potentially more fertile area is dwarfed by the area that will become unsuitable for growing food and survival So, first we know that there’s global warming, that we know the future with super duper certainty, and now, on top of that, we know all the details too! Wow! Sounds like a SECOND hypothesis that needs more proof, to me Look, I get it. AGW is a theory, and there’s some evidence behind it. I get all of what anyone has said. You guys are just over-stating the meaningfulness of the evidence. If you’re honest, you’d never accept this kind of evidence to back up such intense claims to coerce people into spending such atrocious amounts of money, if it came to one of the other sciences. I get it. All the AGW people have to get that you’re never going to make a full sale to the American people. P.S., I could have responded to more, there was some more strawmanning up there, you guys putting words in my mouth, but whatever, I’m not really interested in dragging on this kind of shit ---
**Author:** ![GIGObuster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gigobuster/32/421_2.png) [@GIGObuster](https://boards.straightdope.com/u/GIGObuster)\ **Post date:** [November 27, 2014, 6:08am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/32 "2014-11-27T06:08:47Z")
> [@EdwinAmi](#): > > You guys are saying that climate science isn’t ignoring it, but one of the guys above JUST SAID that there are positive feedback mechanisms before the negative, or something like that That is because the scientists investigated that before, please read about it in the links provided before telling us more baseless claims. > [@EdwinAmi](#): > > Oh yeah, right, that experiment where they built a time machine and slowly tracked all climate data for the past 1,000,000+ years > Oh right… > > Oh, but stupid tree rings are just as good as that, right? Other kinds of science can only make claims they can actually experiment on, with exact precise data whose tiny variance is only allowed to be caused by imperfect measurement machines. > Every single interaction in physics and chemistry and electronics can be explained exactly by the relevant theories, and reproduced 100%. But climatologists get to look at some tree rings and I’m supposed to buy it 100%, and impoverish my entire country. That level of faith? > > So, first we know that there’s global warming, that we know the future with super duper certainty, and now, on top of that, we know all the details too! Wow! > Sounds like a SECOND hypothesis that needs more proof, to me. You are entitled to your opinions but not the facts, the CO2 that is released in the atmosphere by human activities is the same stuff as the past CO2 that is detected in the extracted ice cores, tree rings are not the only items used to get approximate temperatures from the past (three rings by the way are proxies to past temperatures, the estimated temperature they report from the past has limitations so other proxies are used to check them and for deeper timelines.) National Geographic Teaching Guide: > **[Education | National Geographic Society](https://education.nationalgeographic.org/)** > > Engage with National Geographic Explorers and transform learning experiences through live events, free maps, videos, interactives, and other resources. > [@EdwinAmi](#): > > Look, I get it. AGW is a theory, and there’s some evidence behind it. I get all of what anyone has said. You guys are just over-stating the meaningfulness of the evidence. If you’re honest, you’d never accept this kind of evidence to back up such intense claims to coerce people into spending such atrocious amounts of money, if it came to one of the other sciences. The evidence for Tobacco causing cancer, fossil power plants and vehicles causing acid rain and industrial CFCs causing the loss of the ozone layer were accepted before. Then as now the same groups that oppose doing a concerted effort (that will take money, but not at the atrocious lebels **the same groups** misleadingly claim) are telling our politicians to ignore the science. > [@EdwinAmi](#): > > I get it. All the AGW people have to get that you’re never going to make a full sale to the American people. The latest polls show that even with groups like the Heartland Institute, The George C. Marshall Institute and FOX spewing misinformation the majority of the American People do think that the government should do something. [http://www.nytimes.com/2014/10/31/us/why-republicans-keep-telling-everyone-theyre-not-scientists.html?\_r=0](http://www.nytimes.com/2014/10/31/us/why-republicans-keep-telling-everyone-theyre-not-scientists.html?_r=0) > [@](#): > > Since then polls show that the political landscape has changed. A 2013 survey by USA Today and Stanford University found that 71 percent of Americans say they are already seeing the results of climate change, and 55 percent support limiting greenhouse gas emissions from power plants. Mr. Krosnick of Stanford analyzed polls in 46 states conducted between 2006 and 2013 and found that in every state surveyed, at least 75 percent of the population acknowledged the existence of climate change, and at least 67 percent said the government should limit greenhouse gas emissions. > [@EdwinAmi](#): > > P.S., I could have responded to more, there was some more strawmanning up there, you guys putting words in my mouth, but whatever, I’m not really interested in dragging on this kind of shit Direct quotes from you are not what one could call a strawman. ---
**Author:** ![Budget\_Player\_Cadet](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/budget_player_cadet/32/205_2.png) [@Budget\_Player\_Cadet](https://boards.straightdope.com/u/Budget_Player_Cadet)\ **Post date:** [November 27, 2014, 7:32am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/33 "2014-11-27T07:32:13Z")
> [@EdwinAmi](#): > > You guys are saying that climate science isn’t ignoring it, but one of the guys above JUST SAID that there are positive feedback mechanisms before the negative, or something like that I noted that there are positive as well as negative feedbacks. This does not negate the existence of elements of the environment which are negative feedbacks. That said, the way you’re describing feedbacks is _nonsensical_. The climate has changed _significantly_ in the past; where were these negative feedbacks then? Oh right, they were there, _they just don’t work the way you think they do_. > [@](#): > > Oh yeah, right, that experiment where they built a time machine and slowly tracked all climate data for the past 1,000,000+ years How do you feel about creationism? > [@](#): > > Oh, but stupid tree rings are just as good as that, right? Other kinds of science can only make claims they can actually experiment on, with exact precise data whose tiny variance is only allowed to be caused by imperfect measurement machines. We don’t have the most precise data. What we do have is multiple lines of concordant data. The tree rings. The ice cores. The silt deposits. We can get very precise measurements on things like CO2 concentration in the past, and fairly precise measurements on temperature in the past. From this evidence, we can piece together what the climate in the past looked like. No time machine necessary. Again, how do you feel about creationism? Because this is Ken Ham level reasoning right here. > [@](#): > > Every single interaction in physics and chemistry and electronics can be explained exactly by the relevant theories, and reproduced 100%. Yep! Like Pluto’s orbit! We can totally reproduce that! :rolleyes: No, you’re wrong. But more to the point, the fact that certain kinds of modern science can offer a more direct form of proof does not discount sciences that look at the past. We’re all capable of looking at evidence from the past and drawing valid inferences. If I showed you a picture of a city after either a hurricane, a tornado, an earthquake, or , and you had to either tell me what caused it, I betcha 99/100 times you’d get it right without any experimental confirmation. What you’re pulling is a straight-up creationist argument to try to attack all science that examines the past. It’s fundamentally dishonest and I am disappointed that anyone here would make such a bogus argument. > [@](#): > > But climatologists get to look at some tree rings and I’m supposed to buy it 100%, Well, you could examine the [multiple concordant lines of data](http://www.skepticalscience.com/empirical-evidence-for-co2-enhanced-greenhouse-effect.htm) which have led to temperature reconstructions and CO2 reconstructions of the recent past all looking pretty much the same, with slightly different error bars. See, that’s one of those things in science. When you try two different methods and lines of evidence to find out what happened, and each of those ways gives you the same result, usually that’s a pretty good sign that the result is accurate. But again, you don’t understand this. You’re not looking at this evidence. You’re simply making bald-faced assertions with no understanding of the published scientific evidence. _Case in point_. > [@](#): > > and impoverish my entire country. There is decent evidence that indicates that the economics of AGW are [not negative](http://www.theguardian.com/environment/2014/sep/16/climate-change-report-damage-overhaul-global-economy), and very strong evidence that the economic impact of global warming is a [big deal](http://www.climatehotmap.org/global-warming-effects/economy.html). That is, taking action now _is not a bad thing for the economy_, but not taking action could be catastrophic. There’s little to no reason to believe that fighting AGW would destroy the economy or impoverish the country. > [@](#): > > So, first we know that there’s global warming, that we know the future with super duper certainty, and now, on top of that, we know all the details too! Wow! > Sounds like a SECOND hypothesis that needs more proof, to me Tell ya what. How 'bout you spend _5 minutes_ looking for the proof - five minutes looking at the evidence supporting these hypotheses - before you pretend there is none? That would be really swell. You think the evidence is not a strong basis because you aren’t _looking_ at it! You have no idea what you’re talking about. It’s the solar panels thing all over again. You just make bald-faced assertions with no interest in what the actual peer-reviewed literature says, or what experts on the topic have to say. You’ve been demonstrably wrong quite often. At what point do you stop and say, “Jeez, maybe I should go _learn_ something about what I’m talking about, rather than just flapping my gums about a subject I know _nothing_ about?” > [@](#): > > P.S., I could have responded to more, there was some more strawmanning up there, you guys putting words in my mouth, but whatever, I’m not really interested in dragging on this kind of shit Excellent. Then don’t. Your opinion is completely unproductive to any discussion on climate change because, as previously stated, your understanding of the subject is less than zero. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [November 27, 2014, 2:27pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/34 "2014-11-27T14:27:45Z")
**MODERATING** Let’s not make this into yet another thread about the reality of global climate change. We have plenty of those already. Frankly, I don’t think the OP is clearly enough formulated to permit a simple factual answer in GQ terms (other than that an optimum can’t really be determined), nor a focused debate in GD. My inclination is to close this, unless someone can address the OP in a relevant manner. Those who wish to debate any other aspects of anthropogenic climate change may contribute to the existing threads or open another thread on the questions raised by the OP in GD. I am leaving this open for now but if it continues as a general debate on global climate change I will close it. Colibri General Questions Moderator ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [November 27, 2014, 3:00pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/35 "2014-11-27T15:00:14Z")
> [@HoneyBadgerDC](#): > > Taking onto account that we may have to go through some changes while getting there has an optimized co2 level ever been attempted to establish? Not unless you consider current proposals to maintain CO[sub]2[/sub] levels to those we had in 1990 (~350 ppm). Current levels are at ~400 ppm > [@HoneyBadgerDC](#): > > Another related question, is the feasability of removing carbon from the air a real possibility at this time? Is it doable? Yes. Is it economically viable that’s up for debate. [http://www.aps.org/policy/reports/popa-reports/loader.cfm?csModule=security/getfile&PageID=244407](http://www.aps.org/policy/reports/popa-reports/loader.cfm?csModule=security/getfile&PageID=244407) gives a value of ~$600/tCO[sub]2[/sub]. Youc an also read that as how crucial it is to either not emit in the first place, or to capture at the point of emission. It’s much for effective to capture CO[sub]2[/sub] at the coal plant vs. pulling it all back out of the air. > [@HoneyBadgerDC](#): > > And if all the available fossil fuels are used up what is the projected co2 level when that happens? It goes badly - [http://arxiv.org/ftp/arxiv/papers/1211/1211.4846.pdf](http://arxiv.org/ftp/arxiv/papers/1211/1211.4846.pdf) “The practical concern for humanity is the high climate sensitivity and the eventual climate response that may be reached if all fossil fuels are burned. Estimates of the carbon content of all fossil fuel reservoirs including unconventional fossil fuels such as tar sands, tar shale, and various gas reservoirs that can be tapped with developing technology (GEA, 2012) imply that CO2 conceivably could reach a level as high as 16 times the 1950 atmospheric amount.” For references 16 x 1950 CO[sub]2[/sub] would be \>3000 ppm. ---
**Author:** ![Budget\_Player\_Cadet](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/budget_player_cadet/32/205_2.png) [@Budget\_Player\_Cadet](https://boards.straightdope.com/u/Budget_Player_Cadet)\ **Post date:** [November 28, 2014, 8:51pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/36 "2014-11-28T20:51:23Z")
> [@Colibri](#): > > **MODERATING** > > Let’s not make this into yet another thread about the reality of global climate change. We have plenty of those already. > > Frankly, I don’t think the OP is clearly enough formulated to permit a simple factual answer in GQ terms (other than that an optimum can’t really be determined), nor a focused debate in GD. My inclination is to close this, unless someone can address the OP in a relevant manner. Those who wish to debate any other aspects of anthropogenic climate change may contribute to the existing threads or open another thread on the questions raised by the OP in GD. > > I am leaving this open for now but if it continues as a general debate on global climate change I will close it. > > Colibri > General Questions Moderator I’m pretty sure you addressed the OP pretty clearly, and so did I, taking your point further. The optimal CO2 level, at least for us, is the level needed to maintain the climate as we’ve had it for the past few centuries of astounding growth. ---
**Author:** ![FXMastermind](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fxmastermind/32/7289_2.png) [@FXMastermind](https://boards.straightdope.com/u/FXMastermind)\ **Post date:** [November 28, 2014, 10:24pm UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/37 "2014-11-28T22:24:39Z")
> [@HoneyBadgerDC](#): > > Taking onto account that we may have to go through some changes while getting there has an optimized co2 level ever been attempted to establish? Yes, but the figure is up for a lot of debate. > [@HoneyBadgerDC](#): > > Another related question, is the feasability of removing carbon from the air a real possibility at this time? Plants “remove” a huge amount of our emissions already. Irrigating the worlds deserts, with solar power of course, would be the fastest and most economic way to remove carbon. Economic because the plants would have a huge economic value, as well as creating huge areas of land to live on. Making fuel from atmospheric CO2, using solar power of course, would also be good. > [@HoneyBadgerDC](#): > > And if all the available fossil fuels are used up what is the projected co2 level when that happens? Since we don’t actually know how much fossil fuel there is, it’s unknown. There is also the issue of the huge amount being removed all the time. If the known coal reserves were all burned (which would be something like 5,000 years from now), as well as all the unconventional fossil fuels (such as tar sands, tar shale, and hydrofracking-derived shale gas) it could be as high as 1400 ppm, but that is a wild estimate, and meaningless to us at present. > **[What If We Burn All The Fossil Fuels? - MAHB](https://mahb.stanford.edu/library-item/what-if-we-burn-all-the-fossil-fuels/)** > > Introduction by Kirk Smith: Hansen’s latest is difficult to follow in detail because of the complex nature of the arguments, but is available as indicated. Much of the argument is based on the perhaps less controversial studies of historical... ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [November 29, 2014, 12:43am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/38 "2014-11-29T00:43:47Z")
Something I wonder about are the surprises we may get. Animals or plants in the ocean or on land that suddenly start to multiply faster with higher levels of carbon available, possibly affecting the food chain. ---
**Author:** ![FXMastermind](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fxmastermind/32/7289_2.png) [@FXMastermind](https://boards.straightdope.com/u/FXMastermind)\ **Post date:** [November 29, 2014, 12:48am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/39 "2014-11-29T00:48:27Z")
A long term well done study of trees in Maryland reported hard wood trees are growing two to four times faster now, and it is due to increased CO2 levels. > **[Study Finds a Tree Growth Spurt (Published 2010)](https://www.nytimes.com/2010/02/02/science/earth/02trees.html?_r=0)** > > Forests in the eastern U.S. appear to be growing faster in response to rising levels of carbon dioxide. It’s one reason experts think the missing sink (where all the CO2 is going) might just be the forests. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [November 29, 2014, 1:43am UTC](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520/40 "2014-11-29T01:43:12Z")
> [@FXMastermind](#): > > A long term well done study of trees in Maryland reported hard wood trees are growing two to four times faster now, and it is due to increased CO2 levels. > > [http://www.nytimes.com/2010/02/02/science/earth/02trees.html?\_r=0](http://www.nytimes.com/2010/02/02/science/earth/02trees.html?_r=0) > > It’s one reason experts think the missing sink (where all the CO2 is going) might just be the forests. Thats kind of where I was going wit this, could the living bio mass in the ocean increase by 30% for instance. How long would it take those living animals to die and decay back into free carbons. [Previous page](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520.md?page=1) [Next page](https://boards.straightdope.com/t/has-science-determined-an-optimum-co2-level/705520.md?page=3)