Talk:Carbon dioxide/Archive 2

Please standardize units
In the Earth's atmosphere section, it gives tons and tonnes, though not in any consistent order. For the 1999 figure, tonnes are not provided.

Carbon dioxide and Energy in Organisms
Somebody had written

"CO2 is the prime energy source and the main metabolic pathway in heterotroph organisms such as animals, and also a secondary energy source in phototroph organisms such as plants when not enough light is available for photosynthesis"

But this is not true. I deleted it. CO2 is a byproduct of energy production from sugars, fats, etc. Heterotrophs do not obtain any energy from CO2 - indeed I do not think that this would be possible, as CO2 is pretty much as oxidized as carbon is going to get.

PLANTS make SUGARS from CO2 and water using the energy from light - and this energy pretty much runs the entire world's ecosystems (except for those deep-sea thermal vents), but saying plants and animals "get energy from CO2" isn't the same thing. —Preceding unsigned comment added by 71.172.89.50 (talk) 05:10, 31 October 2007 (UTC)

Nothing on producing CO2
How is CO2 made commercially for softdrinks? Dry ice? Other uses? Is it separated from air cyrogenically? Is it made chemically?68.5.64.178 00:39, 1 August 2006 (UTC)

indeed, it is produces from air separation plants, nowadays. —Preceding unsigned comment added by Sikkema (talk • contribs)


 * Sikkema 23:21, 14 January 2007 (UTC) I stand corrected; although some is isolated from air, most is prepared sythetically, either by burning of fuels, and purification of the flue gases, or as a byproduct in industrial processes. An example is the neutralization of waste sulfuric acid, using chalk:

H2SO4 + CaCO3 -> "H2CO3" + CaSO4

Beer production at large breweries make excess amounts of CO2 which is free from unhealthy contamination and used to make softdrinks.

Paleo history of CO2
The page currently gives this source for a graph showing CO2 in the distant past: http://www.geocraft.com/WVFossils/PageMill_Images/image277.gif It's schematic, and the temp curve is substantially incorrect. I suggest changing it to Royer et al (2004). http://www.gsajournals.org/gsaonline/?request=get-document&doi=10.1130%2F1052-5173(2004)014%3C4:CAAPDO%3E2.0.CO%3B, Fig 1. I'll do this if no-one objects :) Tom Rees Tomrees 16:24, 23 Jun 2005 (UTC)

What's the deal with subscript notation?
The two ways to format subscripts (and superscripts) render identically in my browser (Opera 7.54). So what is the "best" format: CO2 CO2  or CO 2  CO 2  and why? The former requires fewer keystrokes, although I'm more used to the HTML form. Vsmith 19:33, 16 Apr 2005 (UTC)


 * The former form 2 uses a template and results in identical HTML as 2 being sent to your browser, hence they would never look any different. Templates live in the template namespace and can be accessed by going to Template:template_name, i.e. Template:sub.  The advantage of using templates such a  is that it will take whatever text is on the page Template:stub and insert it into all pages including the tag: "  ".  You can also pass parameters to templates to customize them.  In the Sub example, the "2" is the parameter being passed to the Template.


 * Templates can be used in two ways either or  .  The subst: in the second form tells the wiki to immediately substitute the entire current text of template into the page (i.e. 2 becomes 2 even in the edit window).  The form without the subst: causes the text to inserted only when the page is loaded, i.e. wikipedia looks up the current form of template each time the page is viewed.  This has the advantage that changing the text at Template:template can immediately change what is presented in all places it occurs.


 * The drawback is that looking up each time a page is loaded increases server load.  For this reason, some people feel that for things like subscripting, which are both pervasive and unlikely to change, that 2 should never be used, and only 2 or 2 should be used.  After all, each of these produces identical code for the browser.  I assume this is why Cburnett replaced the templates.  As far as I know, there is no hard and fast policy on this.  Dragons flight 22:27, Apr 16, 2005 (UTC)


 * Thanks! Now will I remember all that? Guess I'd best apply it soon. :-) Vsmith 23:46, 16 Apr 2005 (UTC)


 * Yes, that's why I did it. There's no real need to force subscripts and superscripts to use a template other than ease of editting (I've actually posed an enhancement that would make it easier by doing 4^^th^^ or 4\\th\\ for superscript and CO^^^2^^^ or CO//2// for subscript) since the sub and sup HTML tags will probably never change in HTML. Using templates for such only serves to increase server load... Cburnett 00:26, Apr 17, 2005 (UTC)


 * Another solution is Unicode. The superscripts are 0x207x and the subscripts 0x208x, as in CO₂. —BenFrantzDale 13:55, 4 November 2005 (UTC)

CO2-only greenhouse
Is it meaningful to discuss the greenhouse effect of a single atmospheric component, as if that could be divorced from the effects of other atmospheric components? If the IR absorption spectra of, say, CO2 and water overlap at all, then the effect of adding more carbon dioxide will depend on how much water vapor is already in the air. And even if they don't overlap, then the amount of outgoing radiation absorbed by one component depends on the spectrum of the outgoing radiation, which depends on the temperature of the radiation source, which depends on the strength of the greenhouse effect of all the other components.

It seems to me that there are multiple plausible ways to deconvolute the effects of a multiple-component greenhouse, and so this statistic is ripe with potential to spin the result one way or another.


 * You are right. While, it is not entirely implausible to define the greenhouse effect of one component (say by asking how much the effect would change by removing all of that component and leaving everything else constant), there are a number of concerns with respect to how one defines that number and people having different ideaologies can reasonably quote different values depending on how they choose to approach the problem.  Consequently, any single value is pretty much inherently POV.  I am going to remove that recent addition.  If the author wants to quote a range of values representative of the NPOV spectrum and add a discussion of the various ways the contribution of CO2 is defined, then I wouldn't object to that.  Dragons flight 17:22, Apr 29, 2005 (UTC)


 * PS. Please sign your statements on talk pages with 4 tildes ~.


 * Considering that the article actually SAYS that there was 20 times as much CO2 in the atmosphere during the Jurasic Era, and presumably there WERE lifeforms here during that time (If Dinosaurs are not simply a figment of our imagination), then it seems implausable that the modest current increase in CO2 is going to have any significant effect on global climate. Water Vapor is currently around 3,000 times the concentration, and is a much STRONGER Greenhouse gas than CO2 (You have only to compare the early morning temperature on a cloudy day during summer with the early morning temperature on a clear day during summer to observe water vapor's powerful Greenhouse effect), any discussion of the Greenhouse effect that omits a discussion of water vapor is flawed. Redwood Elf (talk) 03:13, 9 September 2008 (UTC)

Indonesian peat fires...
The article sez:


 * with Indonesian peat fires recently releasing 13-40% as much carbon as fossil fuel burning does

This has no source. Nor does it state if this is per year; per all time; fossil fules globally or in indonesia... in short, its coming out unless backed up and explained. William M. Connolley 18:43:22, 2005-09-09 (UTC).
 * The source is in #Peat fires in peat link above. (SEWilco 20:48, 9 September 2005 (UTC))
 * Subtle, and not really very helpful. Ive made it rather more explicit. William M. Connolley 21:21:56, 2005-09-09 (UTC).

Merge from dry ice
There was no consensus for the merge here from dry ice. I suggest splitting it out again. Gene Nygaard 22:08, 19 October 2005 (UTC)


 * Yeah, I agree. I was surprised to see it moved here. There was a comment on the Dry Ice page yesterday... not sure where it went.--Bookandcoffee 17:36, 20 October 2005 (UTC)


 * Here's the text from Talk:Dry ice (which you can still get to by clicking the "redirected from" link at the top of the page -- I don't know any way to code no-redirect into a wikilink):

 I agree we should move the physical properties out to the CO2 article. Dry ice, however, is unique amongst solids in that most people think about it separately from the gas. Thus I think it should stay as a separate article. Samw 23:52, 18 October 2005 (UTC)
 * That is fine with me. It was the mismatched physical properties that I did not like. Feel free to do whatever you think will improve the article. Bobblewik 18:06, 19 October 2005 (UTC)


 * Zack 01:58, 21 October 2005 (UTC)


 * Dry Ice is an industrial product manufactured for a specific purpose. It is a separate subject.68.5.64.178 00:39, 1 August 2006 (UTC)


 * I disagree; when discussing water, one cannot avoid talking about ice. "dry ice" is just another form of CO2</SUB>, and people should realize it is the same compound. Unless, of course, we effect a split between CO<SUB>2</SUB> as a chemical comopound, and an article about atmospheric CO<SUB>2</SUB> as suggested above. Sikkema 17:21, 12 January 2007 (UTC)


 * This is illogical -- by your logic, every gas must be in the same article because they are all gasses. Dry ice is a specific product, made for specific purposes. The fact that it is made entirely of carbon dioxide is of no relation to its use. Dry ice should be freed! Scott Adler 08:33, 6 May 2007 (UTC)

(1) The Carbon dioxide article is currently 46KB, too long in my opinion. (2) Dry ice as a commodity is man-made. (3) From a similar case: Water and Ice are separate articles, it does not have to be a "black and white" distinction or exclusion. This is not to say that carbon dioxide as a solid should be expunged from the Carbon dioxide article, just limit the commodity dry ice to a mention and a "See also" link. --Charles Gaudette 21:31, 6 May 2007 (UTC)


 * I agree, it should be split out. The article is too long and should have some sections written summary-style, with links to more specific topics. The same goes for atmospheric CO2, which is discussed below. --Itub 10:13, 8 May 2007 (UTC)


 * I agree with the split. We should leave an introductory stub, and put the main "meat" in the dry ice article. --Rifleman 82 08:27, 11 July 2007 (UTC)

Question
Does anyone know the temperature at which CaCO3 decomposes to CaO + CO2 ?

I am asking this in view of venus' atmosphere. 84.160.210.182 20:10, 4 December 2005 (UTC)
 * According to our article on calcium carbonate, it is 825 °C, which fits with my vague memory of the value. This is at least 300 °C higher than surface temperatures on Venus. Physchim62 (talk) 10:37, 5 December 2005 (UTC)


 * So this could not have been the source of CO2 aon venus. Thank you for the fast answer. 84.160.238.22 20:35, 5 December 2005 (UTC)

The decomposition depends on the partial pressure of CO2. At 600°C the partial pressure is about the same as that of CO2 in the earth's atmosphere. At around 880°C the partial pressure is about 1 atmosphere. At some intermediate temperature it meets the PP of the exhaust gas from the fire heating the lime. But to meet the partial pressure on Venus you would need temperatures over 1100 - prehaps upto 1200°C. There may be other reactions such as reacting sith SiO2 that would liberate CO2. My reference: GB 05:14, 13 July 2007 (UTC)

PaCO<SUB>2</SUB> Mention?
Considering the biological details included in this article, shouldn't a link to the Blood gas application of partial CO2 pressure in medicine be included?
 * I've added it as a "see also" for the time being, rather than mess around too much with a well written biology section. It is there for next editor to include in the text. Physchim62 (talk) 09:36, 11 December 2005 (UTC)

Carbonic acid from CO<SUB>2</SUB>
I need to know the minimum pH that can be obtained by passing CO<SUB>2</SUB> through water a approximately 2bar. Can anyone help me with this one.

Thank you for your time


 * I don't have the answer, but you can check the CRC handbook of chemistry and physics.Sikkema 17:23, 12 January 2007 (UTC)

refrigeration
"Liquid and solid carbon dioxide are important refrigerants, especially in the food industry, where they are employed during the transportation and storage of ice cream and other frozen foods." Dry ice is used for shipping small quantities of frozen items like medical samples or frozen food but I don't think it's used as a refrigerant is it? --Gbleem 03:46, 27 December 2005 (UTC)

I found this : http://www.hepco.co.jp/english/research/develop/result2004/res2004-04.html
 * Liquid CO<SUB>2</SUB> can be used as a conventional refrigerant in industrial circumstances, where it has the advantages of being cheap and non-toxic. The pressures required (50 bar) mean that it is impractical for domestic use. Physchim62 (talk) 08:40, 7 June 2006 (UTC)

Question about capturing CO<SUB>2</SUB>
It is being proposed to capture CO2 with Algae. I accept that this technology will work and that CO2 (e.g. from a coalburning power plant) can be converted in wet Algae material. After drying (preferably some kind of sun-drying) the amount of dry Algae matter (+/-50% Carbon content) is twice as large as the coal mass being applied in the power plant.

What are we going to do with the Algae mass? Burning again? Wim de Groot, the Netherlands

I'm trying to find out what the methods are for capturing, or seperating CO<SUB>2</SUB>. Many coal powerplants are using algae photobioreactor systems to reduce their NOX and CO<SUB>2</SUB> emmisions, but i haven't been able to find out how they seperate the CO<SUB>2</SUB> from the smoke and particulate matter in order to feed it into the algae system.

Also, aside from plants, is there any way to capture/collect/seperate, the ambient CO<SUB>2</SUB> in the air.

Are there any materials that could be used to absorb CO<SUB>2</SUB>, and then later release it.

Aside from pressurizing CO<SUB>2</SUB>, is there a convenient way to store it,(perhaps a large tank).

How do submarines deal with the buildup of CO<SUB>2</SUB>.

Is there an efficient way of producing CO<SUB>2</SUB>, (gasification of coal, etc)

If anyone has information about any of these questions, please post it in the CO<SUB>2</SUB> article.

-Daemon

Answer - I work in the industry. The Algae systems are the most developed CO2 mitigation techn ology out there, but they are still in the prototype stages - the technology is far from being commercially viable. Seriously - go to greenfuel.com they are doing test work on about 0.01% of american power generation - literally 4 or 5 of several thousand american power plants.

A fossil power plant burns fuel that releases NOX, SO2 & SO3 (acid rain), Mercury, CO2, and an amazing amount of heat. The NOX we take out using selective catalytic reduction - basically a giant version of the catalytic converter in your car. the SO2 & SO3 are removed by a properly tuned flue gas desulfurization system. The flue gas is piped through a giant shower of dry limestone powder OR wet limestone slurry, to create a gypsum byproduct, typically sold as drywall. Of course FGD Scrubber also pulls out the heavy metals, ionic mercury, and other nasties from the flue gas, and that ends up in solid waste or waste water. Vaporized Mercury? We can't do much with that yet. Honestly. There are allot of experimental technologies, and a federal law requiring reductions in 2015. But right now mercury control systems are borderline science fiction. We can build stuff that sorta works, but it's still experimental. CO2 is easier than mercury to "scrub" out of the flue gas, but it's on the tail end of a series of scrubbers, and only the young algae technology seems to work well

The updated wiki page has data on C02 capture technology. The most popular now is the ammonia based systems that Alstom is proposing. Which uses lots of power, and like all scrubber technologies, you take it out of the air, you have to put it some where - that's a solid waste issue or a waste water issue.

Currently, 2007, as a Professional that designs and builds Power plant emission control technology.. There is no proven C02 technology that Works at the power plant scale. The most developed and cleanest is the Algae bioreactors, and those are still experimental. The big money is in Amine Scrubbers and "Sequestration" - literally trying to Bury C02. Any scientist will describe that technique as dirty with chemical by products, and a ticking underground time bomb. Photosynthesis is the only CLEAN way to deal with CO2. Every other technique absorbs C02 into a chemical of some sort, and then you have to either dispose of the chemical, or then extract the "pure" co2 and bury it.

How do submarines deal with C02? Easy, they use a superior technology. Called a Nuclear Fission reactor. Very little waste, the only C02 comes from the crew. They can filter that out, release it into the water if they like, and use the reactor to crack the water for fresh oxygen.

Ask any physicist or Power engineer. One power plant to power a few million homes gives you the following options - "Clean" natural gas that pours tons sulfur and C02 into the air every day for an expensive price. "Dirty" coal, that is super cheap, even with emissions controls for the sulfur and NOX, puts out tons of C02, Ash, Scrubber by product per hour. And I mean like 10 tons of stuff per hour. Or a nuke that puts out a few pounds of spent radioactive fuel per year.


 * Here's some info from the Carbon cycle topic in Wiki. "a team reported in the July 2008 issue of the journal Geology that a single typhoon in Taiwan buries as much carbon in the ocean -- in the form of sediment -- as all the other rains in that country all year long combined". Given that Global warming adherents predict that increases in CO2 will result in more violent weather then it's plausable that the same violent weather will sequester the CO2 as described above. Perhaps this is the feedback mechanism that solves the effects of an increase in CO2. Showman60 (talk) 23:06, 22 August 2008 (UTC)

HERES THE BIG PROBLEM.

A Nuke Reactor puts out a tiny amount of solid waste annually, but is expensive to build, and people don't understand the technology. Solar can't produce large scale power yet. Wind farms only work sometimes, and often when you don't need it. Hydro has been pretty well tapped, and we are still figuring out economical geothermal beyond the niche market. So we are stuck for the moment with fossil fuels - burning Coal, Natural Gas, and Oil. No matter what you do, you are stuck with a large amount of Ash, NOX, Sulfur, Mercury, Vaporized metals, CO2, and heat. The heat we dissipate in an environmentally happy way and typically waste. The CO2 we are pretty close to "breathing" away with algae. You can pull all the nasty smoke from fossil fuels out of the air, and then you have it in a liquid or solid form. Easier to control waste, yes, but you still have to do something with the waste. In the end, Nukes put out the smallest amount of waste. But for the next 50 - 100 years or so, we will be spending billions every month on "cleaning" fossil fuels, until there are enough nukes and renewable power supplies to replace them. Which means 50 years of mitigated fossil fuel burning, lots of burying ash and heavy metal, lots of "almost clean" waste water run off. And they only other option is to turn off the power, and freeze in the dark. Our culture is learning, and trust me we are working very, very hard to clean up the world... But we have a long way to go, and we are the generation that will shoulder and correct the mistakes of our fore fathers.

Back to the point - Good news is we can deal with C02 using photosynthesis. The Algae technology out of MIT is maturing just in time. Combined with SCR for the NOX, an FGD for the sulfur, and a little luck for Mercury, burning coal isn't actually that bad.

But the CO2 problem will be solved by Algae, the best photosynthesis we have. And there is no garuntee that CO2 will end global warming, only the hope that we are making a difference.

24.9.13.134 04:22, 20 March 2007 (UTC) TS

How to measure carbon dioxide
Does anyone know of a way to measure the volume of CO<SUB>2</SUB> when it decomposes from copper carbonate  to Copper oxideand carbon dioxide?

Sikkema 17:26, 12 January 2007 (UTC):Prepare a setup in the chemical laboratory with a closed vessel with your (known) amount of CopperCarbonate. From this vessel, you lead a hose into a measuring cylinder that is upside down in ACIDIC water. (e.g. 5% AcOH). Do the reaction (probably heat it up) and read the volume. Presto.

organic or inorganic
I was answering questions from my biology book and a question came up, is carbon dioxide organic or inorganic?

There was a paragraph in the book that said, organic compounds are either found or made by living orgainism, all other compounds are inorganic. Some inorganic compounds thats are essential to living organisms include water, minerals ... and carbon dioxide.

So is it organic or inorganic. Or do I just answer it as both organic and inorganic?


 * The dividing line between organic and inorganic is not always clear. From the organic compound article, it says that organic compounds are a subset of compounds that contain carbon and hydrogen, and since carbon dioxide doesn't contain hydrogen, it's not organic.  The inorganic chemistry of carbon article also explicitly mentions carbon dioxide is inorganic. --Spoon! 06:26, 31 August 2006 (UTC)


 * Sikkema 17:29, 12 January 2007 (UTC) Spoon is right, in science the separator between organic and inorganic chemistry is disappearing, and becoming completely irrelevant. You biology book is incorrect. For example: your blood contains hemoglobin, that transports oxygen through your body, but it does so with the use of iron.

High concentrations of CO<SUB>2</SUB> poisonous?
It says that concentrations of more than 5% of CO<SUB>2</SUB> is poisionous, and this is hinted in articles like Apollo 13, but pages like Asphyxia and Limnic eruption just hints that the CO<SUB>2</SUB> is displacing the oxygen. When I see that we usually breathe out 4.5% CO<SUB>2</SUB>, and 5% is poisionous, I start to think that our lungs are not capable of getting rid of CO<SUB>2</SUB> if there is too much CO<SUB>2</SUB> in the air ... is that right? tobixen 19:26, 24 May 2006 (UTC)
 * The level of carbon dioxide is the main signal used by the body to ensure the correct breathing rate: see air hunger. So yes, excessive levels of CO<SUB>2</SUB> in the air screw up one of the most important control mechanisms in the body, I think that can be defined as "toxic"... Physchim62 (talk) 08:44, 7 June 2006 (UTC)
 * Carbon dioxide also acidifies the blood, so I can imagine that raising the concentration would play havoc with your body. Gas exchange in the lungs is just by diffusion, and therefore limited by the external concentration.  I've worked with dry ice and gotten a lungful of the vapors; your lungs just sort of seize up.  72.57.79.40 00:02, 29 September 2006 (UTC)
 * 5% sounds a little low, but yes you can asphyxiate on higher levels of CO2 And example of this is the lakes in Cameroon, Africa that kill some hundred people and animals when it released a huge amount of CO2.    If your blood pH changes too much your cells do not work properly.  LoyalSoldier 17:17, 31 March 2007 (UTC)

Is plant biomass in the northern hemisphere really responsible?
The article currently claims:


 * Because of the greater land area, and therefore greater plant life, in the northern hemisphere as compared to the southern hemisphere, there is an annual fluctuation of about 5 µL/L, peaking in May and reaching a minimum in October at the end of the northern hemisphere growing season, when the quantity of biomass on the planet is greatest.

According to the Phytoplankton article, "Through photosynthesis phytoplankton produce approximately 98% of atmospheric oxygen."

This doesn't seem to add up. Perhaps phytoplankton removing CO<SUB>2</SUB> from the oceans doesn't affect atmospheric CO<SUB>2</SUB> as immediately as land plants do. Perhaps seasons don't effect phytoplankton CO<SUB>2</SUB> consumption as much as they do land plants. Perhaps lots of things that I'm not thinking of contribute to making the "greater land area in the northern hemisphere" statement correct.

My initial reaction however, is that this explanation needs some confirmation.


 * If you can watch flash, you should view the movie at http://www.daac.ornl.gov/NPP/npp_home.html. This shows the intensity of primary productivity, or carbon fixation, over a multi-year period.  You'll see that terrestrial primary productivity can be far more intense, and is far more variable with the seasons, than marine primary productivity.


 * Honestly, the 98% marine number strikes me as strange, unless it might be based on some confusion between gross and net primary production: maybe phytoplankton do an enormous amount of photosynthesis compared to terrestrial plants, but also consume almost all the resulting oxygen through their respiration. I don't know.  Shimmin 22:31, 29 June 2006 (UTC)

Sikkema 17:37, 12 January 2007 (UTC): Indeed, this seems unlikely, although a mixture of effects cannot be excluded from the discussion. I think that the sun, with its warmth, liberates more CO<SUB>2</SUB> from the northern hemisphere oceans, which is perhaps more productive than the southern half... A search in Scifinder Scolar (scientific database) yields torrents of info. to be continued.

Al Gore in an Inconvent Truth shows that the level of CO2 in the atmosphere reduces when the North is titled towards the Sun, this he puts down to the number of plants growing in this time is increased then when the South is facing the Sun. 98% from phytoplankton does seem too high as well.

% of CO<SUB>2</SUB> in atmosphere error ?
I think that the %figure,.035% routinely used for the amount of CO<SUB>2</SUB> in the atmosphere is in error. This figure is routinely seen on websites used by schools and, in fact, everywhere. The bulk of the air is Nitrogen78%, Oxygen21%, and only .9% (nine tenths of 1 % is left for trace gasses, CO<SUB>2</SUB> is .035% of the trace gasses only, not of the whole atmosphere, which makes it even less than Xenon.  This in turn makes it only .000350% of the whole atmosphere.  So, if CO<SUB>2</SUB> has increased from,lets say, 350 ppm to 380 ppm in the last 100 years, this is an increase of 30 ppm in 100 years .00003%.  If this is not correct I'd appreciate some professional help.Willyger 23:53, 5 July 2006 (UTC)


 * 380 ppm means that it corresponds to 380/1,000,000 times the volume of the total atmosphere, or 0.038%. The figure is correct though 0.035% would be rather out of date.  Dragons flight 00:06, 6 July 2006 (UTC)


 * I concur with the percentage, 380 ppm = 0.000380 fraction = 0.038%. But now I think that the estimate of the mass of CO<SUB>2</SUB> is horribly off.  The article on earth's atmosphere indicates that the mass of the whole atmosphere is 5,000 trillion tons (5E+15 tons).  The current article indicates that the atmosphere is 0.057% CO<SUB>2</SUB> by weight, which would give a CO<SUB>2</SUB> mass of 2.85E+12.  The article however gives a value of 2.94E+9, a difference of three orders of magnitude!  I couldn't source the 2.94E+9 number.  Can anybody else?  Sethery 04:57, 12 July 2006 (UTC)


 * Sethery, you are correct. The mass of CO<SUB>2</SUB> in the atmosphere should be 2.9E+12 metric tonnes. For example: http://cdiac.ornl.gov/pns/faq.html gives t 1 ppmv of CO<SUB>2</SUB> = 2.13 Gt of carbon. Thus 380 ppmv = 809E+9 metric tonnes of C. And converting to the mass of CO<SUB>2</SUB>, (using 3.664 g CO<SUB>2</SUB>/ g C) gives 2.965E+12 metric tonnes of CO<SUB>2</SUB> in the atmosphere. I've modified the article. --B Carey 18:21, 15 July 2006 (UTC)


 * You guys are using the ppm figures for the conditions on the surface. That is incorrect. The scalingheigth of air is about 8.4km the one of CO2 is 5.5km. This means that there is in total only about 2/3rds of what you calculated. (the result is obtained bij integrating the barometric formula) Considering the ppm value constant over the whole atmosphere would be silly in my opinion! —The preceding unsigned comment was added by Geelhoed (talk • contribs) 14:07, 20 March 2007 (UTC).


 * CO2 is well mixed in air, as indeed are all the long-lived constituents. Your figure of 5.5km for CO2 is wrong - where did you get it from? William M. Connolley 14:17, 20 March 2007 (UTC)

It's a simple from the barometric formula. R*T/M/g = 8.3*288/0.044/9.8 = 5550 meter

To make this all consistent, we need to stick to something like (date/date range:ppmv:weight:volume){ref} for before and after. It also needs to be clear if we're talking about ice cores or atmospheric measurements, at what surface level. The references need to refer to sources that are specific and verifiable. Sln3412 00:15, 13 June 2007 (UTC)

Available Fraction error?
This article says, "The ratio of the emitted CO<SUB>2</SUB> to the increase in atmospheric CO<SUB>2</SUB> is known as the airborne fraction." Isn't this backwards? For example, "airborne fraction—The fractional amount of carbon dioxide, CO<SUB>2</SUB>, that remains in the gas phase relative to a given increase in the total amount of CO<SUB>2</SUB> (atmosphere and ocean combined)," according to the Glossary at the American Meteorological Society, http://amsglossary.allenpress.com/glossary/search?p=1&query=airborne+fraction&submit=Search. Jedwards05 03:43, 11 July 2006 (UTC)


 * I originally posed this CO<SUB>2</SUB> % question after seeing http://anthro.palomar.edu/adapt/atmospheric_gasses.htm this lists trace gases as % of the atmosphere (all trace gases put together are .9%) Argon 0.934%, Neon 0.0018%, Helium 0.000524%, Methane 0.0002%, Krypton 0.000114%, Hydrogen 0.0005%, Nitrous Oxide 0.00005%, Xenon 0.0000087%. I'm not an academic, but since they don't even list CO<SUB>2</SUB> in this chart, I'm assuming that it is less than Xenon, and as I originally asserted, that would make it 0.0000350%, but it would make it .035% of the .9% of trace gases, no? Willyger Willyger 00:29, 23 July 2006 (UTC)


 * No, the reason they don't list it is its variability (same as with water vapor). 0.035% of the total is more or less correct. --Itub 06:59, 25 April 2007 (UTC)

What?!
Surely the line "The three vibrational modes of carbon dioxide: (a) symmetric, (b) asymmetric stretching; (c) bending. In (a), there is no change in dipole moment, thus interaction with photons is impossible" under the CO2 model must be completely wrong. Why would it have an absorption spectrum if it didn't have any interaction with photons??!--Deglr6328 03:53, 21 July 2006 (UTC)

Mode (a) cannot be excited by IR absorption. Modes (b) and (c) do change the molecule's dipole moment, and can be excited by absorbing photons. Shimmin 01:07, 23 July 2006 (UTC)


 * Modes (b) and (c) can be excited by electric dipole radiation. Mode (a) changes the molecule's electric quadrupole moment and can therefore be excited by electric quadrupole radiation, though the cross section is much smaller. 72.57.79.40 00:04, 29 September 2006 (UTC)

Question: isn't the presence of dipole moment to establish the possible transitions only an appoximation concerning the first order quantum perturbation theory? Could second order effects like Raman effect excite mode (a)? —The preceding unsigned comment was added by Special:Contributions/ (talk)

poor wording
Why does the wording on the dry ice section seem so bad? Its like the person who wrote it thought he was talking to a bunch of kindergarteners
 * Funny, I came here to say just the same thing. I have started to improve the wording a little.. but it all needs a further overhaul. No offense intended to whomever wrote it but it comes off like something written for a grade 3 science project. I don't have time to do it all right now but if it hasn't been improved later I'll work a little more at it. --CokeBear 00:36, 16 March 2007 (UTC)
 * hi! just found your comments having done a restructure of the dry ice section. It looked like the text was originally lifted from elsewhere... - Zephyris Talk 16:03, 17 March 2007 (UTC)

ppm vs &micro;L/L
These units seem to be interchangable. Should we just stick to one or the other throughout the article?--71.52.169.173 17:10, 23 July 2006 (UTC)

Sikkema 17:45, 12 January 2007 (UTC): I have nothing but admiration for SI zealots; ppm and ppb (and ppt) cannot be accurately defined! Whereas μL/L is an exact number. Let's try to keep to the SI, PLEASE. I haven't the faintest clue what the difference is, for example, between dry, imperial, ton, or tonne. All I know is the metric ton, exactly 1000 kg.


 * If ppm are to be used, then they should be specified as ppmv, for precision. WMC could state this with far greater certainty than I, but it seems to me that ppmv are the units most frequently used when atmospheric scientists discuss CO<SUB>2</SUB> concentrations in the earth's atmosphere.  However, at some point in the past SI zealot Gene Nygaard saw fit to replace all instances of ppmv with &micro;L/L, and no one saw fit to made an edit war out of it, and so it has remained thus to this day.  Shimmin 19:03, 23 July 2006 (UTC)


 * Personally, I prefer ppmv. I think uL/L is more something you see in liquid chemistry rather than gaseous chemistry.  Dragons flight 20:02, 23 July 2006 (UTC)


 * Agree, ppmv is my preference as it seems much more commonly used for atmospheric and environmental chemistry. Vsmith 20:35, 23 July 2006 (UTC)


 * Just to report that as a general reader I found this sudden and unexplained change in units quite troublesome. It triggered a time-wasting search for a definition, which appears to be absent.  There needs to be consistency within the article AND, if &micro;L/L is favoured, an explanation of the equivalence or otherwise of this unit to the one generally used throughout the global warming debate. GardenQuad 10:38, 2 April 2007 (UTC)


 * Agreed. I've changed to ppmv throughout William M. Connolley 11:34, 2 April 2007 (UTC)

Dry Ice Bombs
''Making dry ice bombs. Warm water is mixed with dry ice and then pressurized in a plastic container.''

I found this information to be both interesting and amusing. However, should it really be listed as an Industrial Use for Carbon Dioxide?--216.75.93.104 17:51, 1 August 2006 (UTC)
 * It shouldn't be listed as an industrial use for Carbon Dioxide. I don't think Dry ice bombs are used industrially--Taida 18:08, 1 August 2006 (UTC)

Percent of man made CO<SUB>2</SUB>
According to the Enviornment Agency, about 4% of CO<SUB>2</SUB> emissions are man made. How has this led to such a large % rise in atmospheric CO<SUB>2</SUB>? Rich Farmbrough 13:53 9 August 2006 (GMT).


 * ·  I’ve heard CO2 emissions from human activities are small compared to what’s released by nature.


 * The Earth has a natural CO2 cycle that moves massive amounts of CO2 into and out of the atmosphere. The oceans and land vegetation release and absorb over 200 billion metric tons of carbon into and out of the atmosphere each year. When the cycle is balanced, atmospheric levels of CO2 remain relatively stable. Human activities are now adding about 7 billion metric tons of carbon into the atmosphere every year,which is only about 3–4% of the amount exchanged naturally. But that’s enough to knock the system out of balance, surpassing nature’s ability totake our CO2 emissions out of the atmosphere. The oceans and land vegetation are absorbing about half of our emissions; the other half remains airborne for 100 years or longer. This is what is causing the rapid buildup of CO2, a buildup that dwarfs natural fluctuations.


 * Where does this 100 years or more number come from? Using your numbers, the approx. length of time to remove the human created component is 365*(1-200/(200+7))=12 days.  In other words if the natural sources stopped producing co2 for 12 days, all human added co2 for a year would be removed. 100 years doesn't come close to passing simple sanity checks. (If the nature of this calculation confuses you, read the article on Thought experiments.)  blackcloak (talk) 07:23, 18 January 2008 (UTC)
 * You equation is wrong. Try replacing 7 with infinity, for example. But more than that, the logic is wrong: the 200 is a balance; it isn't available to remove extra. 100 years is probably too short William M. Connolley (talk) 19:22, 18 January 2008 (UTC)
 * Since you do not argue that the 200 and the 7 numbers are wrong, we have a common starting point. The equation is not wrong; it is only valid in the small signal (linear) region, i.e. where 7 is small compared to 200. Notice the equation works when the 7 is replaced by 0. But now that you've raised the subject of going to an extreme limit, use this equation: 365*7/200=12.8days (vs. 12.3 days for the first eq.). So are we going to argue about .5 days? Thought experiments and back-of-the-envelope calculations are very useful because they often allow you to examine the relative magnitude of various (isolated) effects. Here I illustrate how small the human component of atmospheric CO2 loading actually is relative to natural sources. By the way, since current CO2 levels are about twice the minimum to sustain life, if we were to allow this thought experiment to continue for an additional 170 days, all life on earth would start to die. So one way to interpret the result of this thought experiment is to conclude that the atmosphere contains about a half a year of CO2 in reserve to support life on earth. Here the conditions of the thought experiment are that all sources of atmospheric CO2 stop, but all sinks for atmospheric CO2 continue. I still have not seen any computation for the 100 year number, but I'm sure I'll have some objection to the definition of lifetime or half-life to equilibrium, a concept that is not used in physics because equilibrium is "never" achieved in radioactive decay processes. blackcloak (talk) 09:15, 19 January 2008 (UTC)


 * See, for example, and the five references therein.  Dragons flight (talk) 16:55, 19 January 2008 (UTC)


 * From http://www.cmdl.noaa.gov/infodata/faq_cat-1.html#23 (see the references section) Richard001 01:49, 2 February 2007 (UTC)


 * I always wonder why no one bothers to mention the fact that there are more humans alive on earth than ever before in history... at 450 litres per person per day that is some 2.7 trillion litres of CO2 per day that is unavoidable. Shall we start the mass executions now?


 * The whole system is somewhat out of balance and we've changed it fast enough that nature cannot compensate. There is not enough data to show whether nature can or not... but the fact is the damage has been done over many many years and it will take years to sort it out. There is no quick fix, because none of this has been sudden, and sadly politicians aren't often in office on the geological scale needed to follow through. It is easy to make a % rise look immense when dealing with very small numbers. If I have a penny and you give me two more, my money has tripled. It doesn't mean you can now tell me that I can buy a Lamborghini.--CokeBear 00:54, 16 March 2007 (UTC)

Wierd formattting error
Under Concentrations of CO<SUB>2</SUB> in atmosphere, the left picture goes over the text in FireFox. Any ideas on why this happens?


 * Because of Global Warming, silly. Professor Chaos 23:55, 23 October 2006 (UTC)


 * Fixed with a well placed  . Thanks for your help, Professor Chaos! - Jack (talk) 21:33, 5 January 2007 (UTC)

Rise in temperature due to CO<SUB>2</SUB>?
As described in the article CO<SUB>2</SUB> absorbs IR wavelenght also called heat-radiation. How can it affect greenhouse system when it absorbs the energy before it hits the surface? Lord Metroid 15:18, 9 October 2006 (UTC)


 * See greenhouse effect for the details. This article should have pointed you there William M. Connolley 15:35, 9 October 2006 (UTC)


 * Theoretically the wavelengths it absorbs are the lower frequency wavelengths radiated by the Earth and not the higher frequencies radiated by the sun. What the article fails to mention is that CO<SUB>2</SUB> accounts for quite a small amount of the greenhouse effect.  Water vapor accounts for nearly all the effect.  Professor Chaos 00:50, 14 October 2006 (UTC)


 * Please sign your posts with ~ . And no, it does account for "nearly all". This is all covered in the GHG article, if you're interested William M. Connolley 08:21, 13 October 2006 (UTC)


 * Actually the GHG article supports Professor Chaos's view. The argument that seems to be made is that we can't do anything about the H2O since so much of it occurs naturally, but we can do something about CO2, even though human contribute something like 3.5% of the CO2 entering the atmosphere, the rest provided through natural processes. blackcloak (talk) 09:15, 19 January 2008 (UTC)

Yes, water is a very potent greenhouse gas, without it, we'd freeze. However, we cannot control the contents of water in the atmosphere, and is it equal in time, on average. The CO<SUB>2</SUB> levels are within our control. THe contribution of this gas are still under investigation. Sikkema 17:51, 12 January 2007 (UTC)


 * You are missing a key point. Combustion and natural decomposition take carbon in chains with on average 2 H atoms attached to each atom of carbon to co2 and h2o.  Practically, one molecule of water is created whenever a molecule of co2 is created.  This is one reason why water and carbon dioxide are intimately connected when discussion greenhouse effects.  blackcloak (talk) 07:23, 18 January 2008 (UTC)
 * It doesn't matter. WV has a short lifetime. The GHG article explains this, I think William M. Connolley (talk) 19:23, 18 January 2008 (UTC)
 * Here is the quote from GHG: "Aside from water vapor near the surface, which has a residence time of days, most greenhouse gases take a very long time to leave the atmosphere." There is no reference, no indication of how close to the surface, no indication as to what percentage, in the air column, of atmospheric H2O is in the surface region. Here the term residence time is used, instead of one of the variants of lifetime used elsewhere for CO2, leading to more confusion. Even you used the term lifetime, apparently incorrectly. I note that you chose not to argue the point that one molecule of H2O is formed along with each molecule of CO2. Of course, each molecule of H2O added due to combustion/decomposition represents a much smaller percentage of the atmospheric H2O than in the corresponding case for CO2. But the GHG article makes it clear that a positive feedback mechanism is in place for WV and that on a relative scale, H2O has a far greater GH effect than CO2. blackcloak (talk) 09:15, 19 January 2008 (UTC)


 * I've seen in a recent documentary, "The great global warming swindle", that the CO<SUB>2</SUB> level in the atmosphere actually lags 800 years behind the temperature variations over time. This is due to the water mass taking roughly 800 years to reach the same temperature as the land. Taking this time-delay into account, core-samples seem to indicate CO<SUB>2</SUB> level in the atmosphere neatly following temperature as it's solubility in water changes. Although CO<SUB>2</SUB> is in our control, it is a negligible factor: Mankind contributes 6.5 Gigatonnes of CO<SUB>2</SUB> / year. Volcanoes produce more, while animals and bacteria are good for 150 Gigatonnes. Rotting vegetation. And the oceans contribute the most to the level of atmospheric CO2. --87.64.132.65 13:11, 21 March 2007 (UTC)


 * The program you refer to was itself something of a swindle. The lag of CO<SUB>2</SUB> in the ice core record (if real, and the ice-age/gas-age calculations are a complication in this) seem to indicate that CO<SUB>2</SUB> was not initiating pre-anthropogenic climate change; however, it may well have been contributing - perhaps substantially - to it as part of the feedback loop. That we are massively affecting the atmospheric CO<SUB>2</SUB> content cannot be doubted given the ice core record, so it is pointless to say our contribution is minor; it is overflowing the capacity of the planet to absorb on human timescales. At least one of the participants (Carl Wunsch) bitterly regretted becoming involved in this program; it is best taken with a big pinch of salt. Orbitalforam 17:36, 1 May 2007 (UTC)


 * This article should not be a discussion of the details of carbon dioxide and the specifics of climate change, but rather the substance itself. Details should point to specific articles about the details. Sln3412 00:18, 13 June 2007 (UTC)


 * Following your logic, all references to greenhouse gases should be eliminated. blackcloak (talk) 07:23, 18 January 2008 (UTC)


 * volcanoes also project sulfur dioxide into the atmosphere. This may have a cooling effect, in some circumstances after an eruption the earths surface temperature has actually dropped in the years following. http://www.cmar.csiro.au/e-print/open/greenhouse_2000e.htm

--Uranium-junkie 09:18, 4 July 2007 (UTC)

Proposed split into Atmospheric carbon dioxide
I feel that most people, when they look up CO2, will be looking for information entirely on this subtopic. Therefore in order to provide that in enough depth - and keep this chemistry page free from clutter - I suggest we make a split. The new page could properly talk about the greenhouse effect; and changing concentrations over time, and the effect of that. Also, if anyone thinks they have a better name for the title or ideas to add to the new article, that would be much appreciated. Thanks :) - Jack (talk) 15:31, 11 January 2007 (UTC)
 * I feel that extra details of atmospheric CO2 would probably be better placed in greenhouse gas, which is a bit short at present. sbandrews 14:59, 19 January 2007 (UTC)
 * Putting it into GHG sounds like a good idea William M. Connolley 15:14, 19 January 2007 (UTC)
 * Good idea about the split. I agree with sbandrews and William M. Connolley about merging the information with greenhouse gas.  --Plumbago 16:26, 25 January 2007 (UTC)
 * split is good, but maintain some text here too. I agree somewhat about moving it to GHG, but would like to flag the possibility of problems as yet unforseen. I guess they can be dealt with as they come though. --naught101 03:10, 29 January 2007 (UTC)


 * I'm inclined to favor the creation of a separate article, and not a merge into greenhouse gas. I think there is enough information that could be said about atmospheric CO2 to easily overshadow everything presently written in greenhouse gas.  For example, the text here hardly even touches on sources, sinks, or residence time.  Dragons flight 04:50, 29 January 2007 (UTC)

I suggest merge into greenhouse gas as a first step; if in the future it gets long enough, merge-out individual "xyz gas in the atmosphere" articles. Maintain a summary section in this article, and a summary section in greenhouse gas (if it ever merges out). -- Stbalbach 04:55, 30 January 2007 (UTC)


 * I agree with the suggestion for a split to a separate article with residual text here. I initially searched for "Atmospheric C02" and was surprised not to get a quick result.  It may be a greenhouse gas, but it's also the most prominent and discussed of them, and people will be looking for, say, the charts in this section more than those for all greenhouse gases combined.  All imo, of course. 142.177.47.93 20:29, 31 January 2007 (UTC)


 * It should probably be created sooner or later given the importance of the subject. There is a lot more we can write about here (e.g. management of CO2 in plants), though for now greenhouse gas is pretty small and this article isn't overly large, so it's not something that must be done urgently. Richard001 00:40, 2 February 2007 (UTC)

I feel splitting the article is extremely important because it would focus mainly on the fact of atmospheric CO2 and Global Warming, a major issue in the world today. It is one of the largest factors that changes the conditions of the earth. Split it! 24.149.134.138 03:09, 28 February 2007 (UTC)EDeMeo

I agree. I came here looking for an article on atmospheric carbon dioxide. Prefer a separate article than a merge with GHG due to the volume of CO2 specific information. Phil153 17:56, 12 March 2007 (UTC)

I support the creation of an Atmospheric carbon dioxide page. The section is already too long for the CO2 article and the subject warrants a separate article. (StefanosK 14:51, 3 May 2007 (UTC))

I just split it into Carbon dioxide in the Earth's atmosphere. There was too much information for Greenhouse gas, which really doesn't overlap at this point. The way, the truth, and the light 06:33, 16 May 2007 (UTC)

Vandalism
Eh, Guys... Can somebody take the "i luv jer i luv jer i luv jer i luv jer i luv jer i luv jer i luv jer i luv jer" out of the Origins part of the article? I would my zelf, but i have no clue on how. Some idiot probably thought he was funny. 62.163.98.243 00:31, 7 February 2007 (UTC)

Some Cleanup
I noticed that portions of the article on the need for inserting carbon dioxide into greenhouses weren't referenced and were also inaccurate. I've done some cleanup, but there are still some claims I can't substantiate - outside my field of expertise. 200.121.111.113 17:36, 27 February 2007 (UTC)

Greenhouse Gas
The discussion of CO2 as a suspect greenhouse gas belongs further along in the article, not the opening paragraph. The Greenhouse and Global Warming debate is still open to much debate, still in infancy, to be so bold and conclusive as to be presented in the opening paragraph. Show the scientific method a little respect, else wiki will remain an unacceptable source of knowledge in schools and colleges. —Preceding unsigned comment added by 68.188.180.22 (talk)


 * "Global Warming" is only up for debate insofar as details need working out (sometimes important details). The broad outline of anthropogenic emissions affecting the climate has been accepted by the scientific community for more than a decade (and was already accepted by many scientists two decades ago).  That one can find individual scientists who dispute it only tells you that science is a broad church.  That these scientists appear in the media in a 1:1 ratio with scientists who hold to the scientific consensus only tells you that the media's definition of "fair and balanced" is unrepresentative and non-meritocratic.  --Plumbago 09:10, 2 March 2007 (UTC)


 * P.S. In future, add your post to the bottom of a Talk page. The top is always old items which people don't read anymore.  --Plumbago 09:10, 2 March 2007 (UTC)

And, I too, am secretly an FPS. I've probably pwned you before in BF2! Not really, you probably pwned me a few times. Anywho, more on the CO2 'greenhouse' debate, which indeed, is still much of a debate - as it seems. A warming trend, in my opinion, is about 50/50 correct, depending on how one interprets the data vs. the urban bubble effect. As urban areas grow, so does CO2 and temperature (not as related as a layman may assume) - meaning not really global warming, but regional warming. As I have noticed in the Detroit (USA) area for about 20 years. What started my fascination was - I knew the local weather was reported from Detroit Metro Airport. I haved lived north, west, and east of the airport, and my local weather was always about 1 degree C cooler. I've been following this for years. I even called a local broadcaster regarding this phenomena, and all they said was 'interesting'. That was 1993. Since then, and after much research, I remain convinced urban areas are about 1-2 degrees C +/- of suburban, especially rural areas. I have also discovered in order to obtain many records, citizens must pay $25 and more for an electronic listing, which is highly suspicious as my tax dollars have been funding these records for decades.

Oh, thanks for the tip of adding comments at the end. I'm a wiki noob. I want to create a wiki account as you have. Cheers bro. —Preceding unsigned comment added by 68.188.180.22 (talk) 05:22, 3 March 2007


 * Please note - this is a page for discussing improving the article and not for original research or general ranting about global warming. Vsmith 15:55, 3 March 2007 (UTC)

And you also take note, keep 'geenhouse gas' out of the 'opening paragraph'. It is still up to debate. Period. Keep the article concentrated on CO2. There is already an appropriate section discussing it's suspect role as a greenhouse gas. It does not belong in the opening paragraph. GL and Greenhouse debate is still up for much debate for exactly this reason - some amatuer makes an 'assumption' early on, then the rest of the project is skewed. Let the already established section of the article spark interest. Else some school kid will base his research under the Assumption made in the first four lines.


 * I'm sorry, but CO2 is an important greenhouse gas. I'd challenge you to produce even one peer reviewed piece of research in the last 50 years that disputes that CO2 contributes to the greenhouse effect.  Dragons flight 02:39, 4 March 2007 (UTC)


 * Ok, I'll bite. Here is a 2007 article that challenges current mythology.  It has 132 references, so that should keep you busy for a while. http://www.oism.org/pproject/GWReview_OISM600.pdf  blackcloak (talk) 04:39, 20 January 2008 (UTC)

Point taken. Let's seperate 'Greenhouse Gas' from 'Global Warming'. Greenhouse Effect is a proven topic. Global Warming is still in debate. Unfortunately, the US media, also other media, has gotten this terribley confused. They blend the two ideas as one. Maybe best left alone. Danke Schone. I'll sleep on it. I want the two seperated, but might be beyond my repair of the abhorant ignorance the media insists.


 * I repeat: this page is for discussion of the article and how to improve it. Please keep your comments on topic. CO2 is a greenhouse gas. That is a simple statement of fact irregardless of any connection to global warming. Vsmith 03:43, 5 March 2007 (UTC)

I put in a 'greenhouse effect' gas. Looks a bit better. To leave or omit Joseph Fourier's name? As it seems to imply he discovered the gas. It is all about improving the article, vsmith. It was very misleading before. Misleading, indeed, as artsy folk as Dragon might like. Improvement. Yes.

vsmith, it is a Greenhouse Effect gas, not Greenhouse Gas. Check your wiki links and articles. Global Warming is STILL in much heated debate. "Greenhouse Effect" is not. Now, are you true to you, or true to science? Until you prove CO2 is part of a so-called GL, then leave it out of the opening paragraph. You are puropsely misleading anyone reading this article. —Preceding unsigned comment added by 68.188.180.22 (talk) 03:54, 5 March 2007
 * Please keep personal remarks out of the discussion and please sign with four tildes ~, it's easy. I didn't revert that last by the way. Now what causes the greenhous effect? Why, I think it would be greenhouse gases, no? So just how is that misleading? Stating that CO2 is a greenhouse gas is not an attempt to push any global warming pov - just a factual statement. Vsmith 04:06, 5 March 2007 (UTC)
 * vsmith, thanks for the info. I'll check the 68.188.180.22 04:15, 5 March 2007 (UTC).  Maybe in a couple of years, I'll be an admin.  Probably not.  Please, check the Greenhouse Gas and Greenhouse Effect articles.  You will see they are very different, and why one is still in debate and reads like a Discovery Channel doom and gloom, the other very straight forward.  I will try to keep 'personal' comment out in the future.

Regarding the unity of opinion between scientists: People on the list of 2500 IPCC scientists claim that they had to threaten with legal action in order to be removed from that list. If you state something for the IPCC (International Panel for Climate Change) and they cut half out of it, you are still considered a contributor. It is a purely political body. They reverse cause and effect with regard to the CO<SUB>2</SUB> - Temperature relation and the fact that vineyards could be found all the way up to scotland around the 13th century is also omitted. I refer to the documentary "The great global warming swindle"... --87.64.132.65 13:44, 21 March 2007 (UTC)<P> "The great global warming swindle" - Great documentary. I think it should be mentioned somewhere in this document.


 * "The Great Global Warming Swindle" would be better mentioned in the article on global warming. The fact is, CO2 absorbs infrared light, therefore it could be a "greenhouse effect" gas, not taking into account it's very low percentage of the atmosphere and the fact that it is heavier than air, yet the "greenhouse effect" takes place roughly 12 miles above the Earth's surface.  Whether or not it is contributing to global warming should be mentioned in the global warming section.  Let the CO2 article discuss the chemical.208.242.58.126 (talk) 18:18, 21 March 2008 (UTC)

I think there really needs to be a note, such as "Carbon dioxide is believed by most scientists to be a greenhouse gas" or similar, because chemists don't seem to think it's a GHG. Being a chemist, I'd have to agree--I've only seen it a product of heat and not a cause. So I'd like to see it as what I stated above, not a declarative, possibly offensive statement. Driver 97 (talk) 07:28, 4 May 2008 (UTC)


 * There is not the slightest doubt that CO2 is a GHG, ie its (essentially) transparent to SW but absorbs in the LW. This is a fact of laboratory measurement and has nothing to do with measurements of the earths temperature. The question, does CO2 cause the earth to warm up, is a different one. Is that perhaps what you meant? William M. Connolley (talk) 10:34, 4 May 2008 (UTC)

Well, er, yes, since Joe McAverage will just connect GHGs to warming. So that would work. Note that GHG =/= warming.Driver 97 (talk) 10:10, 7 May 2008 (UTC)


 * Well, err, now we've established that you don't actually want the edit you've suggested to be made, could you say what you actually do want? William M. Connolley (talk) 20:44, 9 May 2008 (UTC)

That the typical connection that GHG=Warming be altered. What I mean by that is to have something that notes that GHGs=\=warming. Because CO2 doesn't cause warming, it's a result of.Driver 97 (talk) 15:19, 14 May 2008 (UTC)


 * Are you from an alternative universe in which doesn't absorb infra-red radiation?  If so, contact your local Wikipedia chapter about making this edit.  If not, perhaps you need to consider emigration to this universe.  --Plumbago (talk) 15:26, 14 May 2008 (UTC)

Possible alternative atomic structure
When takeing my chemestry test I noticed another possibility. Is this possible? .. :O |>C: :O ..

I counted up all the electrons for each atom and they all equal 8 Carbon starts out with 4 and requres 4 more. Oxygen has 6 electrons and requires 2 more so if every atom shares one electron with every other atom, every atom should contain 8 electrons and should be stable. -Hamster2.0 20:39, 10 March 2007 (UTC)

Nope, Carbon has 6 there.
 * That doesn't mean anything. The octet rule is only a nice guideline. Sort of like NO2 has a radical electron orbital.   However that structure would be unstable. LoyalSoldier 17:21, 31 March 2007 (UTC)


 * If you add two hydrogen atoms to the carbon, then you have dioxirane, a known molecule (although there's no wikipedia article about it yet). But that's no longer an isomer of CO2, I'm afraid. --Itub 14:01, 21 March 2007 (UTC)
 * The molecule that you have drawn is a carbene, and not a particularly stable one at that... Physchim62 (talk) 17:32, 22 March 2007 (UTC)

Deleted text about how much CO2 is in the rocks
The following text was removed 01-12-2007 by Sikkema

<ul>If all the carbonate rocks in the earth's crust were to be converted back in to carbon dioxide, the resulting carbon dioxide would weigh 40 times as much as the rest of the atmosphere. </ul> It was originally added 03-11-2004 by Flockmeal

Since I found no discussion about this change, I was wondering if the data was wrong. If it is correct, I think it should be re-added, if it is wrong, then an explanation is necessary since this statement has been on line for almost 3 years and at least 100 other pages quote it (based on a Google search).

Q Science 08:37, 12 March 2007 (UTC)


 * Rough calculation suggests this correct to at least within a factor of a couple. Dragons flight 00:44, 6 April 2007 (UTC)


 * The solution is very simple. Where is the reference? --Itub 08:56, 10 April 2007 (UTC)


 * It is reported in The CO2 Inventory of the terrestrial Planets that Ronov, A. B. and A. A. Yaroshevsky, Geochem. Int., 13, 89-121, 1976 estimate that crustal carbonate rocks contain about 3.4e20kg of CO2. Qemist (talk) 00:21, 27 July 2008 (UTC)


 * Some more figures that support the contention that the amount of CO2 locked up in carbonate rocks is large. Qemist (talk) 00:56, 27 July 2008 (UTC)

inconsistency of when Thilorier discovered dry ice
In the history section in Dry Ice (section 4.1, not section 8), it is stated that Thilorier discovered dry ice in 1825. In section 8, however, the year is 1834. I believe 1834 is the correct year, not 1825. Ctchou 02:27, 14 April 2007 (UTC) —The preceding unsigned comment was added by Ctchou (talk • contribs) 02:26, 14 April 2007 (UTC).

Mosquitoes
In the "alternate uses section" it is mentioned that it's coldness could be used to repel mosquitoes. This idea may be self-defeating due to the attraction of the carbon dioxide gas. Just another guy trying to be a Chemical Engineer, Nanobiotechnologist, and Mathematician 02:40, 17 April 2007 (UTC)

True, some mosquito traps utilize dry ice to attract the mosquitoes. I found a .org source http://www.cababstractsplus.org/google/abstract.asp?AcNo=20043033251 Could someone remove it, I'm a newbie and not shore on the right way to go about it. --Uranium-junkie 08:38, 3 July 2007 (UTC)

Good article delisting
I removed this article from GA status, as I feel it doesn't make the grade. The reasons are as follows: These should be fixed before the article can claim GA status. Also, the GA listing didn't seem to go through the correct procedure — Jack · talk · 19:08, Tuesday, 24 April 2007
 * not enough references
 * multiple fact tags, on some quite risqué claims
 * references poorly formatted
 * citation cleanup tag
 * external links cleanup tag
 * split tag
 * extensive see also section
 * a lot of bullets and number list that should be prose
 * excessive chemical equations
 * poor ordering and flow
 * poor tone throughout, particularly in a scientific sense

Triple Point
From the article: "Liquid carbon dioxide forms only at pressures above 5.1 atm. Its triple point is -56.6 °C at 416.7 kPa...".

416.7 kPa is 4.1 atm, not 5.1 - unless I am missing something? Gingekerr 09:32, 22 May 2007 (UTC)


 * 416.7 kPa is 4.1 atm, that is correct. However, I'm not sure which is the correct value for the triple point. I have found some books that say 5.1 atm, one that says 5.0 atm, and one that says 4.1. If anyone knows an authoritative source for this information, please add it to the article. --Itub 14:26, 6 June 2007 (UTC)


 * I know this is late, but I adjusted the wording to show that the pressure needed depends upon temperature. Sln3412 00:25, 28 July 2007 (UTC)

Liquid?
The NFPA 704 symbol says "(liquid)". Obviously CO2 isn't usually liquid. Shouldn't the NFPA 704 say "gas"? 141.149.12.44 02:05, 30 May 2007 (UTC)
 * That's how it's stored. — Jack · talk · 22:00, Monday, 4 June 2007
 * It would be rather pointless to have a box full of co2, 'cuz it is harmless (and mixes with air quite easilySln3412 02:28, 13 June 2007 (UTC)) if under normal pressure/temperature! So yeah, the NFPA 704 is for stored stuff.  Sln3412 02:28, 13 June 2007 (UTC)

Ice cores
Ice Cores - any link to information on CO2 in ice cores ( popular argument for CO2 level changes ). Is CO2 in ice cores unchanging - level remains the same over time - ie no absorption, etc. Are there other measures that provide records of historic CO2 levels? Are levels of CO2 in ice totally dependent on atmospheric CO2 levels? Thanks.159.105.80.141 13:45, 5 June 2007 (UTC)


 * Try the following link: Carbon_dioxide_in_the_Earth's_atmosphere that should answer your questions — Jack · talk · 18:47, Tuesday, 5 June 2007

Thank you - a lot to read in a small place.159.105.80.141 12:41, 8 June 2007 (UTC)

Revising references & broken link
While harmonizing the references in this article, I noticed the following link which appears to be broken. In Section "7 Carbon dioxide sequestering", list item "Serpentine, Olivine, Quicklime", reference [20] pointed to http://www.tececo.com/sustainability.tececo_kiln.php

The reference is deleted, but maybe somebody finds an appropriate alternative? Ioverka 02:48, 12 June 2007 (UTC)

Mixing volume and weight, link to Shukman news story
"The 20 year smoothed Law Dome DE02 and DE02-2 ice cores show the levels of earth's atmospheric CO2 to have been 284.3 ppmv (0.02843% by volume) in 1832.[8] As of January 2007, the measured atmospheric CO2 concentration at the Mauna Loa observatory was about 383 ppmv, which is 0.0582% by weight.[9] This is a rise of 98.7 ppmv, or 25.7% of the 1832 ppmv level."

We should change these to read either weight or volume.

"This represents about 2.996 tonnes, and is estimated to be 105 ppm (37.77%) above the pre-industrial average."

I also removed the link to the BBC News web site referencing the number of tonnes of CO2 -- the number's rather meaningless, and the story didn't have it in there anyway. Also, the story has no reference itself to what that pre-industrial average was (amount nor time). I replaced it with the calculation of 284.3 to 383

If anyone has valid links to how much is in the atmosphere for both time periods, or more specific referenced information on what constitutes the "pre-industrial average" in both amount and time period (e.g. average of year x to year y was z), please update with everything in weight or volume, or add weight and volume for both sets of information. (If you read the article on pre-industrial society, and then the link to industrial revolution, that time mentioned could be in the 'late 18th and early 19th century' or 'pre-1780s' or before being 'felt in the 1840's' or happened 'between 1760 and 1830'.)

FYI, I also put paragraph divisions between the paragraphs.

Sln3412 23:28, 12 June 2007 (UTC)

Update of all sections
I've tried to redo every section to make it better in and of itself, but haven't done much with either references or general flow of the article itself. Most of what I've updated is "referenced" by including links to other articles with the references.

Other things to do?

If once we define "carbon dioxide" as being "CO2" if we use one or the other or mix them

If levels include "ppm" with the numbers, use something like "5000 ppm (.5%)" or "5% (5000 ppm)" or just numbers or just percentages or mix them between paragraphs

How much detail on what to DO about carbon dioxide itself in the atmosphere etc

Sln3412 02:20, 13 June 2007 (UTC)

Toxicity
This article mentions (more than once) the toxicity of carbon dioxide, but never says why. I think the article could be improved by discussing exactly what higher levels of carbon dioxide do the human body. This is what I came to this article for.Squad51 19:37, 13 June 2007 (UTC)
 * It is not toxic in the poisonous sense, but exposure leads to problems since a given volume of it will displace oxygen. Someone want to write this up for the wiki? Also, the brain monitors the ratio of the partial pressures of CO2 and O2 in the blood (referred to as pO2 and pCO2) and responds to increase circulation and breathing to maintain sufficient O2 delivery to itself (the brain burns the most sugar, and therefore uses the most O2) and other tissues. Cowbert 21:41, 14 June 2007 (UTC) Cowbert


 * CO2 in large concentrations is harmful even it's not displacing any oxygen. Try breathing a mixture of 20% oxygen and 80% CO2 and see what happens! --Itub 08:04, 5 July 2007 (UTC)


 * We already know what would happen. You'd die. Sln3412 00:24, 28 July 2007 (UTC)


 * CO2 has other effects on your body such as messing with your buffer system and other such things. LoyalSoldier 05:47, 20 October 2007 (UTC)

Dubious "ever before"
Do we have a source that has a credible person claiming that that current [CO2] is the highest it's ever been on the planet? What about towards the end of Snowball Earth? Please, let's have some perspective here. Ufwuct 09:50, 20 June 2007 (UTC)


 * You're right, its wrong. I've removed the whole para - there is a separate article for atmos CO2, and the graph is enough here William M. Connolley 10:11, 20 June 2007 (UTC)


 * You're correct, it's been over 7000 before, millions of years ago. Now is only higher than anytime in the last few hundred thousand, at least if you directly compare the atmosphere to the ice cores.  I must have meant since humans have been around or something....  However, I would think it might be worthwhile mentioning the levels rising 99 ppmv over 170ish years, 70 of that has been in the last 45ish, or the .15 a year rise from 1832 to now compared to .67 from 1960 to now.  The graph only shows from 1960.  Just a thought. Sln3412 21:59, 20 June 2007 (UTC)

Opening Paragraph
I would like to suggest that, "Carbon dioxide is present in the Earth's atmosphere at a concentration of approximately .000383 by volume (383 ppm)," in the introduction paragraph be moved from the introduction paragraph into an expanded section discussing C02 concentrations. CO2 concentration varies throughout local and global geographies. Also, introduction paragraphs should contain a summary or into for the material and subject matter to follow. This statement does not serve that purpose.


 * Its an important matter that people are likely to be looking for, which argues for keeping it in the intro. But 383 is unnecessary precision (how about 0.0004)? You're right, the conc varies William M. Connolley 21:55, 26 June 2007 (UTC)
 * I never liked the 0.000383 number; people's eyes tend to glaze over when confronted with lots of zeros after the decimal point. Guess the same would apply to 0.0004. I'd prefer just 383 parts per million, or maybe we could say 0.04 percent. Raymond Arritt 22:40, 26 June 2007 (UTC)
 * Good points. A percentage or ppm # would be more appealing to the eyes.  Several zeros stick out.  Maybe that's why I noticed the intro paragraph.


 * If we're discussing a rise of over 125 years of less than 100 ppm, rounding 383 to 400 is too much. It's "around 385 ppm by volume"   We should use entire numbers, nearby but not exact, sure.  But if the strength of CO2 is such that rising from "285 to 385" is causing major problems, rounding it up 15 is excessive.  Sln3412 00:39, 7 July 2007 (UTC)

Human Physiology
Okay, after a little bit of trawling I found the source that the original author(s) wrote the section with. I also added in the citations from it, the source seems reliable because it has it's own references at the bottom etc. Hopefully I have got the ball rolling with the source. Now, all the section needs is some cross referencing and it should be fine. I noticed at the top of the page that the article needs more print referencing, when I get home from work today I will try and get on that. I hope some other wikipedians try and help with the Article Improvement Drive! :-) Scarian  08:36, 5 July 2007 (UTC)
 * There's also wiki pages on the haldane effect and the bohr effect. A lot is also explained in the appropriate sections of respiratory system  Sln3412 19:17, 12 July 2007 (UTC)

Unbalanced
At the middle of Carbon dioxide, if R-MgX + CO2 → R-COOH means what I think it means, it's unbalanced and wrong. Where does the Mg go, where does the X go, and where does the H come from? Art LaPella 04:04, 6 July 2007 (UTC)

Art LaPella 05:28, 6 July 2007 (UTC)

Uses
I was surprised that an article this size about such an important topic didn't have "Uses" section, so I added a short list as a start. But now that I looked into the history, oh, surprise! There used to be a quite detailed uses section which was deleted by a vandal in 2006 and no one seemed to notice. Not a good example for those who claim that vandalism in Wikipedia is generally reverted within minutes! :-( In any case, I have restored the section. It could use some references, though. --Itub 08:00, 11 July 2007 (UTC)


 * Perhaps there is a separate article on uses for CO2 that removed the need for it? I don't know, just guessing.  A lot of the sections could use more references, though including that one, yes.  Sln3412 18:58, 12 July 2007 (UTC)

Plant respiration
The lead states that carbon dioxide is exhaled by animals and inhaled by plants. That's fine, but I thought carbon dioxide is also exhaled by plants as part of plant respiration. This is seperate from photosynthesis. See here. Cheers--Shahab 07:34, 12 July 2007 (UTC)


 * True. That needs a bit of rewriting.  The net action of plants is to consume CO2, but there are large gross production and consumption fluxes (consumption must dominate though, otherwise animals would have nothing to eat!).  The portion immediately following about respiration in plants is even worse though - it's entirely context-free.  I'll see what I can do when I have some more time.  Cheers, --Plumbago 08:23, 12 July 2007 (UTC)


 * I was under the impression intros should summarize and then the body of the article would explain in detail and give the references. The isolation section explains both combustion and biological reactions, and has links to appropriate articles with details, and industrial production refers to the Kirk-Othmer chemical encyclopedia on other specifics.  There's also more detail in the biological section and subsections.   Some of those sections might need refs (there is in fact a 'citation needed' in the bit about "Plants also emit CO2 during respiration, so it is only during growth stages that plants are net absorbers.")  The context is in the body, although perhaps not enough. Sln3412 19:10, 12 July 2007 (UTC)


 * Also see Respiratory_system and Respiratory_system Sln3412 19:19, 12 July 2007 (UTC)

Extra coverage
There should be some extra parts to this article. GB 03:55, 13 July 2007 (UTC)
 * Physical properties, such as it absorption spectrum and how that causes a greenhouse effect. off in carbon dioxide (data page)
 * Green house gas emissions - how humans produce the gas and how much.
 * greenhouse gas reductions - what it means for carbon dioxide
 * geochemistry - how CO2 is added and removed by the earth by weathering, volcanoes, limestone, subduction etc, and how that has changed over the life of the earth. Also inlcude solubility in the ocean and how it is affected by heat.
 * there must be a main article for CO2 in photosynthesis to link to

complete split-up
I propose a complete split; this is the article on CO2, as a chemical and its uses, so there should only be a small refernece to a main article on the CO2 in the atmosphere, and the effects that has. Thoughts? Sikkema 23:39, 6 July 2007 (UTC)


 * I don't really agree. As the dominent AGW GHG, the role CO2 plays in absorbing and transfering heat is of at least some importance in this context. Sln3412 00:22, 28 July 2007 (UTC)

Critical point
This article lists the critical point of CO2 as 31.1°C. At it says 30.9782 C, or 31.0°C. Any reason for this 0.1 degree difference? Rangek 21:15, 13 August 2007 (UTC)

Reactivity of carbon dioxide
The article states that carbon dioxide is not very reactive. I diasgree with this statement. Carbon dioxide is actually quite reactive. It supports combustion ie 2Mg + CO2 --> 2MgO + C, it reacts with almost any basic material, forms compounds (as opposed to salts) with ammonia or organic amines (the production of urea is particularly notable), reacts with organolithium coupounds or Grignard reagents to make carboxylic acids and so on. If no one objects, I will reword the sentence in question.Silverchemist 02:50, 25 August 2007 (UTC)


 * I would not object as CO2 is actually reactive in quite a few cases. A few examples are with hydroxides. LoyalSoldier 05:49, 20 October 2007 (UTC)

Can't find the source
the line: "Amounts above 800 ppm are considered unhealthy" in the chemical and properties section, i can't seem to find the source backing this up. Jozsefs 10:30, 5 September 2007 (UTC)


 * Thinking about this... lets hope >800 isn't that unhealthy, because its possible a century from now William M. Connolley 11:03, 5 September 2007 (UTC)


 * Well there's already been highs of >800 measured in urban centres such as paris and phoenix, and i'm sure there's more cities that reach this level. so i think it's important  to see a source confirming that it's an unhealthy level. Jozsefs 11:46, 5 September 2007 (UTC)


 * My suspicion would be that it's not the CO2 per se that's the problem, but rather that 800 ppm is usually associated with other industrially-driven air quality issues (particulates, sulfates, ozone) that do cause problems. Only a hunch though, but it might help in tracking down a source.  --Plumbago 12:11, 5 September 2007 (UTC)

Just here putting forward a revision that could be done. Do you all think this really belongs in the article? It seems to be referring to water vapour a lot more then carbon dioxide.

"Although water vapour causes a substantial fraction of the total greenhouse effect, its contribution relative to carbon dioxide is believed to be relatively static, and it complicated by its counter-balancing positive- and negative-feedback loops[11]. While water vapour acts as a greenhouse gas by absorbing longwave radiation, condensed water forms clouds that reflect shortwave radiation from the sun (although clouds also trap heat in cold areas, and too much vapor condenses and falls as rain). For these reasons, water vapour is almost never considered a forcing, but rather almost always a feedback." —Preceding unsigned comment added by 121.45.236.142 (talk) 03:39, 9 September 2007 (UTC)


 * I agree. This does not belong in an article about carbon dioxide.Silverchemist 14:05, 9 September 2007 (UTC)


 * Agree. I've cut it, and a lot more. I don't see why this section should be so large - there is a see-main section for details William M. Connolley 14:50, 9 September 2007 (UTC)

I found a reference issue for reference (13). The wiki states "It is observed that due to human activities such as the combustion of fossil fuels and deforestation, the concentration of atmospheric carbon dioxide has increased by about 35% since the beginning of the age of industrialization.[13]" while the referenced site (http://www.noaanews.noaa.gov/stories2005/s2412.htm) states that CO2 levels have increased by 36% between 1958 and 2004. This is should be fixed. Freeztar 01:58, 8 November 2007 (UTC)

The current link to reference 36 no longer works. I have found a pdf version on the same site - Your Role in the "Greenhouse Effect" by Jerry Hannan. This states a slightly lower figure of "445 liters" of carbon dioxide per person per day. Another article in the New Scientist - Biosphere 03 April 1999 gives a lower figure of 350 litres of carbon dioxide per day. Tut-uk (talk) 19:18, 23 March 2008 (UTC)

Persistent vandalism
For some reason I can't fathom, this is by far the most vandalised article on my watchlist, and usually by anon IPs. Aside from the obvious solution of semi-protecting it, which I appreciate the vandalism may not be severe enough to warrant, does anyone have 1) Any idea why this article is vandalised so often; or 2) Any ideas for how to combat this? No more bongos 12:17, 13 November 2007 (UTC)


 * I don't know what other articles you have on your watchlist, but I have mainly chemistry-related articles and I agree this one is ofte vandalized. That must be because it is one of the most famous chemical compounds, especially with global warming and all that. In any case, I think semi-protection would be a good idea. --Itub 19:13, 14 November 2007 (UTC)

Pure thoughts
In the section "animal toxicity", after a paragraph referring to concentrations such as "5% by volume, or 50,000 ppm" and "0.5% (5,000 ppm)", it says "These figures are valid for pure carbon dioxide". What is this getting at? How could it be otherwise?

The next sentence also refers to "pure outdoor air", but since air composition varies everywhere, isn't it a contradiction in terms?

I haven't changed it as I don't know if there some specialised usage involved here. 220.239.11.110 (talk) 00:28, 17 December 2007 (UTC)

Request energy generation to CO2 generation conversion
What I can't find here, and I do think this is the place for it, is an equivalence for energy production to CO2 quantity (kg). I often read that "replacing this bulb saves nnn kg CO2 per year" or some such. We've all seen it. I'd like some referenced calculations for this. (Probably a U.S. national average of electricity generated by electric utilities.) 169.237.215.179 (talk) 23:34, 19 December 2007 (UTC)
 * Update: I found the source as a Department of Energy report. I will include it in the main article. Thanks. 169.237.215.179 (talk) 23:44, 19 December 2007 (UTC)


 * Depends on the fuel source used to generate the electricity, varying from a maximum for a coal-fired powerplant to near zero for hydropower or wind. Average numbers for the U.S. are on the order of 0.5-0.6 kg CO2 per kilowatt-hour. See e.g., here. For a country that relies heavily on nuclear generation (such as France) or hydro (such as Norway) the numbers will be very different. Raymond Arritt (talk) 23:41, 19 December 2007 (UTC)

Euthanasia -livestock and labs
CO2 is often used in the agricultural and pharmaceutical industries to euthanize livestock or laboratory animals. Neither of these uses appear to be mentioned.

In livestock slaughtering, it's used for things like swine processing. The pigs are loaded onto an elevator which lowers them into a pit where the CO2 is held (as it's slightly heavier than air and tends to sink). They then have a main artery (I believe it's usually the cortid, but I've seen what I suspect to be pulmonary arteries for cattle) cut to drain the meat; as normal after electrical or captive bolt stunning. I'm not sure, but I think the CO2 for livestock processing is only used to get the animals into an unconscious state, as it usually helps drain the meat if the animal's heart is still beating by pumping the blood out of the tissues more efficiently; meat full of blood is not good for general sale. I think in labs the animals are exposed until brain death occurs. I think this method is mainly used for pigs, not large animals like cattle.

I believe in both examples the animal need not be stunned prior to exposure.

Neither I believe CO2 is a humane method of euthanasia, as rich concentrations of the gas stings when inhaled (particularly through the noise) to the extent that you'll involuntary cough it back out and pull away from the source.

Monoxide or another an anesthetic would be less painful, but also present a risk to the staff, require more effective seals and careful handling, could taint the results and would generally be more expensive in total. I'm not sure why an asphyxiate like N2 isn't used. Which is both cheap, can be stored in liquid bulk format, doesn't sting when inhaled and makes up a whopping 80% of the normal atmosphere anyway. It could also be generated on site using zeolite filters. From a quick google, liquid N2 is around 3 - 30 times cheaper than CO2 as well.

I'm not a vegetarian or PETA member and I know other cost effective methods of euthanasia are also somewhat stressful or painful, I just think this information is a worthwhile addition to the article. And, as I say (being in support of animal testing when it's needed and eating meat), I would like to be sure the blanket excuse of it being painless is based on actual fact; particularly with this being a scientific article. From my experience of inhaling the gas, the idea of suggesting it's like 'falling asleep' is simply meat eating / animal testing denial, and I do agree with the vegetarians / vegans / PETA that blanket denial like that is not fair if you're using the results.

I didn't edit the article since I don't have enough solid reference material and wanted to put it forward for discussion. But I have certainly seen CO2 being used for both examples and I am virtually certain rich CO2 does sting when inhaled. I don't know whether it's a receptor response to the CO2 it's self or if the CO2 is forming a weak acid at the mucus membranes; as CO2 is not a noble gas, not inert and does react to some extent (e.g. acid rain and Metal Active Gas welding, also evidenced by it not being used in science when an inert atmosphere is required, it functioning in things like photosynthesis in energetic reactions and the article it's self).

I am going to add a line to the welding section, as I am more sure of what I'm adding there.

"It's all there, black and white, clear as crystal! You stole fizzy lifting drinks! You bumped into the ceiling which now has to be washed and sterilized, so you get nothing! You lose! Good day, sir!", "You're a crook. You're a cheat and a swindler! That's what you are! How could you do something like this, build up a little boy's hopes and then smash all his dreams to pieces? You're an inhuman monster!", "I said good day!" - Willy Wonka —Preceding unsigned comment added by 82.24.47.178 (talk) 17:16, 6 July 2010 (UTC)

Carbon Dioxide More Soluble in Colder Water
The "In the Ocean" section says "Generally, gas solubility decreases as water temperature increases. Accordingly the ability of the oceans to absorb carbon dioxide from the atmosphere decreases as ocean temperatures rise."

I don't know if that's even generally true, but it doesn't seem true for carbon dioxide as per http://jcbmac.chem.brown.edu/myl/hen/CO2Water.gif http://www.kgs.ku.edu/PRS/publication/2003/ofr2003-33/P1-05.html ("The solubility of CO2 in fresh water increases with increasing pressure, decreasing temperature") etc. It looks a lot like ad hoc research.


 * Reference could be made to Henry's law instead. If a citation is still needed: http://pubs.acs.org/doi/abs/10.1021/cr60242a003 145.97.222.186 (talk) 23:56, 2 January 2010 (UTC)


 * Henry's law is irrelevant because it is predicated on fixed temperature. Qemist (talk) 10:21, 3 January 2010 (UTC)


 * Are you claiming that the statement "the solubility of CO2 increases with decreasing temperature" contradicts the statement "the solubility of CO2 decreases as water temperature increases"? That amounts to a denial of logic. Qemist (talk) 10:21, 3 January 2010 (UTC)

Generally solid forms of matter are more dense than their liquid forms. Accordingly, ice sinks. —Preceding unsigned comment added by 67.188.114.26 (talk) 20:42, 1 February 2009 (UTC)


 * (1) Open a cold can of Coke(TM). Then heat another can of Coke by soaking in boiling water for 5 minutes, and open it. Compare. (2) Add ice cubes to a glass of water. Wait for the ice cubes to sink to the bottom and report how long it takes. Short Brigade Harvester Boris (talk) 20:51, 1 February 2009 (UTC)


 * Just to clarify you'll be waiting an eternity for the ice to sink - remember Titanic? It hit a floating iceberg! Smartse (talk) 19:29, 26 April 2009 (UTC)

CO2 has increase solubility in water at lower temperatures. This is an entropic effect. Entropy effects are more pronounced at higher temperatures (DG = DH - TDS). Gases are more disordered when they are free, than when they are dissolved (with no exceptions afaik). So dissolving a gas is entropically unfavorable. This means that dissolving CO2 is unfavorable, and becomes increasingly moreso at greater temperatures. I'm not sure why this is a controversy, since we all know that a cold soda holds it's fizz better than a warm one. The second issue is pressure over of a gas over a container. Greater CO2 pressure over a liquid increases it's solubility in that liquid as well. This is also an entropy issue (Although is commonly taught as equilibrium). This is Henry's law, and it is true for CO2 as well. Breath on a liquid, and it dissolves CO2, acidifying it. Again - this is common knowledge: If you open a can of soda, and let the CO2 leave, it will run flat, because the partial pressure of CO2 above the liquid lowers. Re-add pressurized CO2 above the container, and it will regain its fizz (it wasn't magic how it got there in the first place). Seriously people, there isn't any controversy or confusion over any of what was just "discussed" above. — Preceding unsigned comment added by Dmitchwk (talk • contribs) 09:55, 5 February 2011 (UTC)

383 ppm or 385 ppm? - or 387ppm and increasing...
At the introduction at top the CO2 in atmosphere is stated as currently "approximately" a global average of 383. Later in the article in the CO2 in atmosphere section it is stated as 385 ppm. I understand this number is fluctuating as it trends upwards but it seems that these numbers are the same and should be stated as the same value with a citation to the source. 70.110.62.8 (talk) 00:17, 13 February 2008 (UTC)


 * It is indeed constantly changing. There is a secular trend, and annual variation too, and geographical variation William M. Connolley (talk) 22:20, 31 March 2008 (UTC)


 * In addition, the diurnal temperature variations, local volcanic emmisions, photosythesis activity, humidity, air pressure, pressence of operational aircraft, etc. can all have significant impact on atmospheric CO2. It is believed that the sampeling procedure is sufficient to account for these mechanisms of variation.  The mole ratio is determined only after extracting the water vapour, for instance.  Expressing this as a level of CO2 in atmosphere is incorrect and the source authors state this clearly.  These approximations perhaps could be supplemented by the percentage of CO2 in atmposheric air when including water vapour, along with the rate of variability i.e. 0.00383% ± 0.00025%(not the actual numbers, just an example of form)

IanKDavis (talk) 13:32, 2 February 2009 (UTC)


 * The concentration really is quite out of date now - current concentrations (global seasonally-adjusted sea-level average) are estimated to be over 387 ppm (http://co2unting.com) - about 1% higher than the 383ppm stated here. Perhaps the current rate of increase could also be added here, as surely that is of considerable interest too?217.28.34.132 (talk) 11:33, 29 December 2009 (UTC)

CO2 deaths!
An axient that killed a CO2 worker. -ttp://www.youtube.com/watch?v=zkWeZ1YPI88&feature=related

I'm trying to find out how much volume is made by liquid co2. If I open up a standard 12 gram c02 cartridge, how much volumetric air will be made? say in a balloon.

Thanks —Preceding unsigned comment added by 67.164.65.21 (talk) 16:06, 1 May 2008 (UTC)


 * Well, for back-of-the-envelope computation you can assume that CO2 is an ideal gas. In that case, it will take up 22.4 l per mol under standard conditions (which again is close enough). The molar mass of CO2 is 12 (Carbon)+2*16(Oxygen)=44g/mol. So the volume of gas from a 12g cartridge is 12/44*22.4l, or a bit more than 6l. I would say that is one fairly large balloon full of it. --Stephan Schulz (talk) 09:48, 8 June 2008 (UTC)

Carbon dioxide is also called Carbon and that needs to be noted
Environmentalists, policy makers and people in the media always refer to carbon dioxide as just "Carbon." It needs to be noted. —Preceding unsigned comment added by 67.117.145.109 (talk) 19:45, 2 May 2008 (UTC)

Seriously, guy. Stop undoing my edits. Read anything dealing with CO2 emissions and watch them use the terms carbon dioxide, carbon and CO2 interchangeably. —Preceding unsigned comment added by 67.117.145.109 (talk) 19:50, 2 May 2008 (UTC)


 * A section mentioning that might be useful, but Carbon in that context could also include Carbon Monoxide. "Carbon footprint" refers to the amount of Carbon released into the atmosphere in whatever form. I will not revert it again only because I might violate the three rv rule. Please revert it yourself. VMS Mosaic (talk) 19:57, 2 May 2008 (UTC)

I believe that most people who refer to carbon dioxide as "carbon" do it just for the brevity of the name, and therefore, I am afraid that it will have to stay. However, I personally don't like it. There are some people out there (and perhaps an awful lot of them) that don't understand that carbon dioxide is at the bottom of a chemical potential energy well compared to carbon and therefore it isn't energetically favorable to just take it out the the atmosphere, turn it into a solid and bury it in the ground like the coal (or whatever) from which it was derived. I believe that calling carbon dioxide "carbon" further confuses this issue, and I wrote a somewhat whimsical letter to the editor of my local paper bemoaning this situation,. As a result, I have been heckled by a few at work, but have been encouraged by many others to pursue this campaign, and by one to introduce my proposed brief name for carbon dioxide, "carba" on Wikipedia. I would like some peer opinion on how widespread the use of a name has to be to include it in the other names section before I dare add it. —Preceding unsigned comment added by 71.222.183.220 (talk) 02:37, 2 July 2008 (UTC)


 * It's just plain laziness, just like calling lysergic acid diethylamide "acid". People just pick the shorter or more pronounceable word and ignore the rest. --Itub (talk) 11:29, 3 July 2008 (UTC)
 * Yes, the lysergic acid diethylamide article is a good example. It mentions "acid" in the text, but the infobox gives only the various actual chemical names. "Carbon" is not considered to be a chemical name for CO2. VMS Mosaic (talk) 17:53, 3 July 2008 (UTC)
 * I think it's more technical illiteracy (aka stupidity) than laziness. If someone calls both carbon dioxide and carbon "carbon", what are they talking about when they speak of removing so many tons of "carbon" from the atmosphere? Calling carbon dioxide "carbon" is just illiteracy. Some people call whales "fish" and chimpanzees "monkeys"; should the relevant wikipedia articles use the terms interchangeably? Qemist (talk) 22:51, 26 July 2008 (UTC)

They call it Carbon because that name sounds dirty like soot and they don't want you to know they are talking about carbon dioxide. Don't fool yourself they are not doing it by mistake. Thats why you will see objections if you try to clear it up. The latest pro cap and trade ads show it as charcoal brickets. --Sattmaster (talk) 03:39, 7 April 2009 (UTC)


 * LOL, there is no end to the conspiracy it seems! Seriously, it is just a shorthand. A gardener or farmer might talk of needing to add "nitrogen" but he isn't talking of wafting nitrogen gas over his plants or crops, he's talking of compounds containing nitrogen. A person is said to be short of "iron" if they are anaemic, but their body isn't lacking in lumps of the metal. However it is sometimes useful to speak of "carbon" as we're interested in the carbon cycle in which carbon cycles between carbon dioxide in the atmosphere, carbonates in water and minerals, carbohydrates in plants etc. At no point though is it pure, elemental carbon. —Preceding unsigned comment added by 78.149.9.132 (talk) 21:11, 27 December 2010 (UTC)


 * Well, in the scientific literature they usually use the term carbon to talk about all emissions that will in a reasonably short term degenerate into CO2. CO2 is, more or less, the lowest energy form of carbon in the atmosphere. CO, methane, unburned fuel, etc., i.e. nearly any emission of stuff that contains any carbon, will fairly quickly (minutes to years) be oxidized into CO2 (and often some water and possibly some other stuff). Since all this eventually ends up as CO2, the convenient way to discuss it is to just talk about the carbon in it. If you look at reliable statistics, you will see that "carbon emissions" will typically be much lower than "CO2" emissions - by a factor that is a bit smaller than 11/3 (the molecular weight of CO2 is 44, that of pure C is 12, 44/12=11/3, but "Carbon" includes the non-CO2 Carbon emissions). --Stephan Schulz (talk) 05:50, 7 April 2009 (UTC)

CO2 I'm confused please help
If CO2 causes Earth to heat up, why is Mars so cold with most of it’s atmosphere being made up of CO2? —Preceding unsigned comment added by 97.89.59.10 (talk) 01:52, 8 June 2008 (UTC)
 * The greenhouse effect is driven by the absolute amount of greenhouse gases. Mars has less than one percent of Earth's atmospheric pressure. It has nearly no water vapor, which is a major greenhouse gas on Earth. And it receives less than half of the energy per surface area from the sun, just by being farther out. --Stephan Schulz (talk) 09:13, 8 June 2008 (UTC)


 * Mars' ice caps are shrinking, too. Apparently, the warming is not caused entirely by "greenhouse gases." http://news.nationalgeographic.com/news/2007/02/070228-mars-warming.html Captqrunch (talk) 14:55, 23 July 2008 (UTC)


 * Please read page two of that article, at . "His views are completely at odds with the mainstream scientific opinion" and "the idea just isn't supported by the theory or by the observations" should give you some idea about then reception of Abdussamatov's nonsense. --Stephan Schulz (talk) 15:07, 23 July 2008 (UTC)

Extraterrestrial CO2
I removed the reference to CO2 in Mars's atmosphere from the introductory paragraphs of the article. It was out of context and seemed irrelevant. CO2 has been detected on several planets and in interstellar clouds. It's presence on Mars is nothing remarkable or informative about CO2 per se. Perhaps a section on extraterrestrial CO2 could be added.Qemist (talk) 00:23, 27 July 2008 (UTC)

Interesting facts
The problem with this discussion is that it falls over at the first hurdle, by specifying an unsubstantiated figure for carbon uptake by a 25-y tree that, I submit, is out by several factors of ten. Think about it. An Aspidistra could fix more carbon than that per annum. At 1.15 kg per annum, in 100 years your twenty five year old maple will have increased in mass by the equivalent of a young girl. Not credible, as you would discover it fell on your car. I don't care whose web site states that figure, it is not a peer-reviewed source, and the figure is not credible. Consequently, nor is the result. This sort of wild discussion brings WP into disrepute. It should be removed from the main page and carried out on the talk page by experts in the subject until a stable consensus is reached. Plantsurfer (talk) 08:20, 9 September 2008 (UTC)
 * The factor is off by 25 is my guess (judging by this) - its figure is 1,300 pounds of carbon per acre per year - and my guess is that the tufts website got the "per year" part wrong (they say 1,200 pounds of carbon as well - but over the lifetime of 25 years). So i'd say the tuft reference is wrong - and the figures are off by 25 (just as your rough calculations indicate). --Kim D. Petersen (talk) 13:53, 9 September 2008 (UTC)

Cheyne- Stokes breathing and CO2
The Physiology section of this article notes that CO2 blood gas level is a "trigger" for breathing reflex, which is correct. However, it also states this is the only trigger, which isn't so. Cheyne-Stokes breathing (often a form of agonal breathing) depends on PPO2, not PPCO2.

My first contribution --- appologies if this isn't to spec. —Preceding unsigned comment added by 98.115.175.25 (talk) 22:38, 17 October 2008 (UTC)

Hypercapnia
How about someone create a link to the "hypercapnia" page? either in the toxicity, human physiology, or the links at the bottom of the page? —Preceding unsigned comment added by 69.72.23.142 (talk) 08:50, 21 November 2008 (UTC)

Carbonates
So, PL wants to add:


 * There is some concern that as a result of increased in the atmosphere the acidity of seawater may increase and adversely affect organisms living in the water. In particular, with increasing acidity, the availability of carbonates for forming shells may decrease. No explanation for the mechanism has been suggested however

(the bit in bold is what he wants to add). I don't think that is defensible William M. Connolley (talk) 21:56, 13 March 2009 (UTC)


 * Nope, it's not defensible. The mechanism is very well known and in fact is quite obvious when you look at the basic chemistry. See e.g., here. Short Brigade Harvester Boris (talk) 22:32, 13 March 2009 (UTC)


 * Bop him then :-) William M. Connolley (talk) 22:51, 13 March 2009 (UTC)

The current sentence does not refer to the buffering action of bicarbonate at all, and the discussion does not mention the data from our geological past when CO2 levels were higher and stimulated plankton growth. The amount of CO2 locked into limestone and chalk during the Jurassic and Cretaceous is evidence of how organisms in the sea were absorbing vast quantities of atmospheric CO2. So the topic ought to be treated with some balance. Peterlewis (talk) 06:52, 14 March 2009 (UTC)

Looking at the "Basic Chemistry" laughable as there is nothing basic about the chemistry in the environment. If we keep in mind that the ocean is buffered by silicates then looking at that reaction the acid level should remain constant. —Preceding unsigned comment added by 58.172.194.93 (talk) 12:26, 27 May 2009 (UTC)

I (username: eyrryds) would like to add the following: -

NOAA states in their May 2008 "State of the Science FACT SHEET for Ocean Acidification" that:

"The oceans have absorbed about 50% of the carbon dioxide (CO2) released from the burning of fossil fuels, resulting in chemical reactions that lower ocean pH. This has caused an increase in hydrogen ion (acidity) of about 30% since the start of the industrial age through a process known as “ocean acidification.” A growing number of studies have demonstrated adverse impacts on marine organisms, including:

• The rate at which reef-building corals produce their skeletons decreases.

• The ability of marine algae and free-swimming zooplankton to maintain protective shells is reduced.

• The survival of larval marine species, including commercial fish and shellfish, is reduced." The Intergovernmental Panel on Climate Change (IPCC) writes in their Climate Change 2007: Synthesis Report:

"The uptake of anthropogenic carbon since 1750 has led to the ocean becoming more acidic with an average decrease in pH of 0.1 units. Increasing atmospheric CO2 concentrations lead to further acidification."

In particular the IPCC states in it's last report that: "While the effects of observed ocean acidification on the marine biosphere are as yet undocumented, the progressive acidification of oceans is expected to have negative impacts on marine shell-forming organisms (e.g. corals) and their dependent species. {WGI SPM; WGII SPM}" Also in this same report the IPCC states that with probability >0.66 the resilence of many ecosystems is likely to be exceeded in this century by an unprecedented combination of climate change, associated disturbances (e.g. flooding, drought, wildfire, insects, ocean acidification) and other global change drivers (e.g. landuse change, pollution, fragmentation of natural systems, overexploitation of resources)." Marine calcifying organisms (like coral reefs) have been singled out by many major research agencies like NOAA, OSPAR comission, NANOOS and the IPCC because current research shows that ocean acidification should be expected to impact them negatively.

--

Note: You can find references to the above statements in http://www.pmel.noaa.gov/co2/OA/ and of course in the IPCC report freely available in their website. —Preceding unsigned comment added by Eyrryds (talk • contribs) 16:07, 10 November 2009 (UTC)

Just learned how to sign Eyrryds (talk) 17:01, 10 November 2009 (UTC)

Confusing Statistics
I find one part of this article needlessly confusing:

"However, emissions of CO2 by human activities are currently more than 130 times greater than the quantity emitted by volcanoes, amounting to about 27 billion tonnes per year.[25] Human CO2 emissions amount to 2-3% of the natural emissions, including ocean outgassing. [26]"

I think a simple chart, ranking all sources of atmospheric CO2 by percentage, from highest to lowest, would make it much easier to understand these two statistics. No percentage figure for oceanic outgassing is currently given, for instance. The reader is left to guess that outgassing is probably the biggest single source of atmospheric CO2. But it's all abit vague.

Presumably the number and size of active volcanoes emitting CO2 changes all the time. Or do they balance out, to give a more or less constant figure? Please clarify. —Preceding unsigned comment added by Georgesdelatour (talk • contribs) 08:04, 31 March 2009 (UTC)


 * I took out Human CO2 emissions amount to 2-3% of the natural emissions, including ocean outgassing. [26] because it is septic FUD and needs to be stomped on. Volcanoes are episodic, I suppose. Don't understand The reader is left to guess that outgassing is probably the biggest single source of atmospheric CO2. But it's all abit vague - it sez that anthro CO2 is 130x outgassing William M. Connolley (talk) 10:24, 31 March 2009 (UTC)


 * William M. Connolley, please explain why it is so called 'septic FUD that needs to be stomped on'? If we're going to add volcanoes as a source, all other natural  sources should be added too. It can easily be argued that nearly all natural  sources are episodic or variable. For example, wildfires are highly episodic and the decaying of plant life and such (due to drought, disease or otherwise) is highly episodic as well. Also, if we're going to compare human  emissions with volcanic  emissions, we should compare human  emissions to all natural  emissions. Lastly, I'd argue that it doesn't even matter if a natural  source is stable or variable, it's irrelevant in my opinion, since the  isn't immediately absorbed when emitted. Virtually all  is released into the atmosphere and only at a later time absorbed. Source -> atmosphere -> sink.


 * As stated by multiple sources, the vast majority of all emissions are from natural sources; overall, anthropogenic  emissions are in comparison very small. Adding this information to the article has nothing to do with understating the human impact on our climate or environment, it's just a fact that should be mentioned in an article about carbon dioxide, and especially in the section about carbon dioxide in the earth's atmosphere. It's as if the current data about volcanic  emissions was cherry picked to make it look like natural sources of  are insignificant compared to human  emissions. Especially since the volcanic emissions are compared to human emissions.


 * I'm therefore still confused why you've reverted my contribution to the article twice. I hope you can clear that up. --85.145.30.119 (talk) 15:34, 22 June 2009 (UTC)
 * It is POV by omission. You are forgetting to tell the full story. It is a carbon cycle, which means that for each source, there is a corresponding sink (the oceans suck up around 50% though). Fossil fuel burning isn't offset by a sink, so while human emissions are small in the net total of emissions, it is the reason for the increase in atmospheric CO2. --Kim D. Petersen (talk) 16:57, 22 June 2009 (UTC)


 * On the contrary, the current article doesn't tell the whole story, that's exactly my point. If we're mentioning volcanoes as a natural source, we should mention all other natural  sources as well. I've already pointed out that many, if not all, natural  sources are variable, just like volcanoes. Take these Indonesian wildfires for example. These fires emitted enormous amounts of  into the atmosphere:


 * Wildfires that scorched parts of Indonesia in 1997 spewed as much carbon into the atmosphere as the entire planet's biosphere removes from it in a year...


 * The article is inconsistent, for completeness all natural sources should be mentioned. 85.145.30.119 (talk) 18:57, 22 June 2009 (UTC)
 * I'm sorry. But that particular part (Volcanoes) of the text is about the long-term carbon-cycle. And your assertion about Indonesian wild-fires is wrong. According to the paper it released 130 Tg (tera grams) of CO (it says nothing about CO2), which is the same as 0,13 Gt (giga-tonnes). To compare, fossil fuel emissions per anno is 5.5 Gt of carbon (more in CO2). The (land) vegetation sink alone is 121.3 Gt of carbon, or around 3 orders of magnitude larger than what was released by those fires. —Preceding unsigned comment added by KimDabelsteinPetersen (talk • contribs) 20:13, 22 June 2009


 * Every natural source is part of the (long-term) carbon cycle, not just volcanoes. And about the amount of  emitted, it's not my assertion, it's in this source. But even if the amount of  emitted by these wildfires was less, my point remains: most, if not all, natural  sources are variable and should be added to the article, just like volcanoes. You're arguing semantics. 85.145.30.119 (talk) 12:41, 23 June 2009 (UTC)
 * No, not every natural source is part of the long-term cycle. Try reading up abit on it. The short-term carbon cycle balances (sources==sinks). --Kim D. Petersen (talk) 15:34, 24 June 2009 (UTC)


 * What you're telling me is a gross oversimplification of the carbon cycle, and I must say it's extremely ironic that you're telling me to read up on it. If a natural source releases its into the environment, it's automatically part of the carbon cycle. It's possible for the carbon dioxide to be stored into so called sinks for millennia, but there's always the possibility for it to be released again into the atmosphere. Atmospheric carbon dioxide levels can fluctuate over time because of this. Furthermore, even if some  is stored in a sink indefinitely, it affects the capacity of the sink to absorb additional carbon dioxide. It's therefore not possible to somehow magically exclude a natural  source from the carbon cycle that we have here on Earth. 85.145.30.119 (talk) 17:45, 24 June 2009 (UTC)
 * You are mixing up long-term (centuries to millenia/millions of years) with short-term (years to decades/centuries (for some trees)). The short-term cycle can be seen here, notice how all sources have a sink - except anthro sources (which to around 50% gets sunk into the Oceans (making them acidic). Volcanoes are the only long-term emission source for (aside human emissions), and is offset (on the long term) by limestone-production. --Kim D. Petersen (talk) 18:01, 24 June 2009 (UTC)


 * I'm not mixing long-term and short-term up, I'm saying that every natural source is part of the carbon cycle. I'm taking the carbon cycle as a whole; short-term and long-term. Currently, the article mentions anthropogenic  emissions and volcanic  emissions, but doesn't mention a whole lot of other natural  sources which can contribute to the atmospheric carbon dioxide level. Talking about POV by omission! Also, please remember that the article section we're talking about is carbon dioxide in the atmosphere, it's not about the carbon cycle. 85.145.30.119 (talk) 18:43, 24 June 2009 (UTC)


 * Oh, and btw, volcanoes are certainly not the only long-term natural source. Take the decaying of plants and such for example, it's happening all the time, and for millions of years. 85.145.30.119 (talk) 18:47, 24 June 2009 (UTC)


 * Hey, I'm new, but I wanted to add a comment here. Something didn't look right when I read the paragraph in question. I followed the citation [25], and found on the "Effects" tab of that page the following: "Volcanoes release more than 130 million tonnes of CO2 into the atmosphere every year." This appears to contradict the text as written. Also, an article by the BBC on the NASA OBO states, "Human activities put about 7.5 billion tonnes into the atmosphere[each year]." See . It appears that the paragraph in question is factually incorrect? Rock Bacchus (talk) 16:56, 25 June 2009 (UTC)
 * Be careful when reading. The BBC article talks about carbon, not CO2. In this context, "carbon" refers to the carbon content of emissions that will in a relatively short term become CO2 - mostly CO2 itself, but also CO and methane, and several smaller contributions. Since carbon has an atomic weight of 12, and oxygen one of 16, 7.5 billion tonnes of carbon correspond to 44/12 or 11/3 times that much CO2 - in other words, 27.5 billion tonnes, or more or less the same 27 billion listed above. --Stephan Schulz (talk) 18:17, 25 June 2009 (UTC)


 * The chapter "In the Earth's atmosphere" fails to put carbon (CO2) emissions from use of fossil fuels of about 28 GT to perceptive of total world's total carbon (CO2) emissions of about 790 GT. Also it fails to comment on why this less than 4 percents of total emissions may be big deal. Very good simplification of this topic is http://www.skepticalscience.com/human-co2-smaller-than-natural-emissions.htm, numbers in that simple article seem to check out. If this article has an agenda to promote some political goal by leaving significant facts out, it could be labeled "propaganda" instead of "encyclopedia". Then there is also lot of talk about volcanism, even it is insignificant, and little about other natural causes. Even Pinatubo contributed only about 42 MT of CO2 (Philippine Institute of Volcanology and Seismology). —Preceding unsigned comment added by 208.65.89.208 (talk) 15:42, 10 October 2009 (UTC)  208.65.89.208 (talk) 00:29, 11 October 2009 (UTC)Pekka Lehtikoski
 * Still to clarify: Reader of "In the Earth's atmosphere" chapter is mislead to completely false conclusion that human activity is the major source of CO2 emission to atmosphere, and the natural sources are insignificant. This smells like Al Gore kind of sciense. Acceptable presentation would be: Even the human contribution to CO2 emissions is small, it may be one of main factors causing increase of CO2 in atmosphere. BR Pekka Lehtikoski. —Preceding unsigned comment added by 208.65.89.208 (talk) 16:02, 10 October 2009 (UTC)  208.65.89.208 (talk) 00:29, 11 October 2009 (UTC)Pekka Lehtikoski
 * Actually, this discussion of carbon dioxide in atmosphere or in ocean doesn't belong under title [carbon dioxide], but should be in [Carbon dioxide in the Earth's atmosphere] or in [Carbon cycle] articles. —Preceding unsigned comment added by 208.65.89.208 (talk) 22:23, 10 October 2009 (UTC)  208.65.89.208 (talk) 00:29, 11 October 2009 (UTC)Pekka Lehtikoski
 * Later comment: Article is now much better, thank you editors:) 208.65.89.208 (talk) 01:45, 26 October 2009 (UTC)Pekka Lehtikoski

The article says that a 35% increase to 3*10^15 t of atmospheric CO2 (=0.8*10^15 t?) has been cause by humans but humans only account for 2.7*10^10 t per year. This contribution would have taken 29,000 years. Surely something is missing from the explanation. [kg not tonnes so my calc out by three orders of magnitude! May be clearer to stick to gigatonnes throughout] —Preceding unsigned comment added by 81.137.204.39 (talk) 11:17, 31 January 2010 (UTC)