Talk:Carbon cycle

What are the numbers on the carbon cycle picture? I cannot figure this out (I'm doing a school research project BTW). — Ilγαηερ (Tαlκ) 01:09, 23 Sep 2004 (UTC)

try the source of diagram but am still trying to make sense myself http://earthobservatory.nasa.gov/Library/CarbonCycle/carbon_cycle4.html

The black numbers are billions of tons of carbon stored in various reservoirs. The blue numbers are billions of tons of carbon that move from one place to another each year. Another easily accessible article on the carbon cycle is in the Feb. 2004 National Geographic. --Rick Sidwell 21:42, 3 Jan 2005 (UTC)

I wish to pose a question for which I have seen no data either in encyclopedic form or chemical journals. How much carbon dioxide is dissolved and in solution in sea water at typical oceanic depths? It is well know that the solubility of carbon dioxide increases with increasing pressure, my question is really about how much is dissolved in the oceans. I have seen no nomographs or any explanatory notes. It is true indeed that there is some circulation between the depths of the oceans and surface waters but it is quite slow and the tendency for increased solubility with increasing applied pressure holds true for all systems, dynamic or otherwise. I have seen no data at all for the amount of carbon dioxide at the average depths of the oceans which are in excess of 1.5 km. Has this been measured? It would seem easy enough to take a "grab sample" seal it and bring it to the surface for analysis.Petitjean1 (talk) 02:34, 10 August 2008 (UTC)petitjean1

inorganic carbon cycle?

I believe a section on the inorganic cycle is needed as the atmosphere, ocean, sediments, and sedimentary rocks depend on this cycle. This cycle occurs on a much longer time scale as compared to the rapid organic carbon bio cycle mentioned in the article, and this scale is important to geologists such as myself.

Go ahead I reckon. Although the time-scales are longer, it has obvious bearing on the extreme long-term fate of anthropogenic CO2, as well as its regulation across geological time. I'd suggest being careful when you add the text so that there's no confusion regarding processes and time-scales. From personal experience, it's easy to stuff up additions.  :) Cheers, --Plumbago 11:15, 9 March 2006 (UTC)

The graph seems to suggest the anthropogenic emissions of fossil-fuels are part of the natural carbon cycle. This however is misleading. Fossil carbon and biological carbon are distinct and though there is some interplay, fossil carbon by and large has a disrupting influence on the cycle which is one of the most fundamental concerns about climate change. Yes also theres the carbon climate prosses :-)

Is not that called the Long Term Carbon cycle?

Image

I love the image in this article, and think it is wonderfully helpful in understanding the subject, but wouldn't it be better at the top of the page, near the introduction? I know it's a large image, but still... ONUnicorn 21:03, 31 May 2006 (UTC)

Volcanoes

The image would be more accurate if it included a volcano as these are massive emitters of CO2 SmokeyTheCat 13:41, 17 July 2011 (UTC)

No they're not 85.211.137.174 (talk) 23:48, 9 June 2012 (UTC)

Carbon cycle re-balancing

There's a page on carbon cycle re-balancing that might be of interest to carbon cycle fans. I've suggested that it be deleted, but its creator and I would appreciate input from other parties. Cheers, --Plumbago 11:31, 7 June 2006 (UTC)

Need page about geological carbon cycle

Wikipedia needs a separate page about the geological part of the carbon cycle because:

• The term "geological carbon cycle" is widely used.
• In at least one respect it's the most important part of the overall carbon cycle.

The geological carbon cycle consists of:

• Rain and weathering, which remove carbon (CO2) from the atmosphere and wash the carbon (as carbonates) down to the seabed.
• Subduction of the seabed and vulcanism, which pump CO2 into the atmosphere.

Subduction and vulcanism are powered by convection currents in the mantle and therefore by the heat of the earth's core. Eventually the core will cool and subduxction will cease. If no other factor has changed the earth's climate, rain and weathering will continue to remove CO2 but the proceeses which restore it to the atmosphere will cease. Photosynthetic orgnisms will become extinct, so all plants and animals (including humans) will become extinct.

This isn't right, sorry. The primary source of CO2 in the atmosphere is from volcanoes. Yes, CO2 is removed to the sea by weathering, but it would just reach equilibrium with dissolved CO2 without some means to convert the CO2 into rock. This is nearly always done through life, through formation of CaCO3. Venus gives us an idea of what would happen to Earth without this process. Venus was probably very similar to Earth originally, but either life never evolved there, or wasn't able to set up the right feedback cycles to keep the planet's atmosphere in equilibrium. We have enough CO2 here to lead to a similar runaway greenhouse effect and it is mainly formation of limestone by life that prevents it. Good reference here http://www.ic.ucsc.edu/~mdmccar/ocea213/readings/02_C_cycle_Long_T/Berner_1999_GSAToday_A_new_look_Long_Term_C_cycle.pdf Robert Walker (talk)

Sorry, realised that the second part of what I say there is wrong, the CO2 can be removed even without life by formation of limestone from the calcium dissolved in the sea by action of HCO2 on silicate rock. The first part is right though, so long as we have continental drift any CO2 removed in that way just goes into the mantle via subduction and then eventually over geological time comes up again from the volcanoes so it doesn't get rid of it permanently. You can't get rid of it permanently so long as we have continental drift - as I understand it anyway, Robert Walker (talk) —Preceding undated comment added 16:27, 21 June 2012 (UTC)

No, this needs to be put in here, under Long Term Carbon Cycle. Here is a page describing same

http://www.carleton.edu/departments/geol/DaveSTELLA/Carbon/long_term_carbon.htm

80.7.195.184 21:03, 3 February 2007 (UTC)

Wash the carbon as carbonates or BICARBONATES? —Preceding unsigned comment added by 84.120.150.252 (talk) 22:54, 29 December 2007 (UTC)

I've added a section about the geological carbon cycle. It was clearly lacking, mentioned in the table near the head of the article, but with nothing at all about it later in the page.Robert Walker (talk)

Someone just removed the second para. where I said that without the greenhouse effect Earth would be as hot nearly as Venus. I can see why as the way it was expressed was indeed too speculative in nature for the context here. So have put in a new version that explains it better, describing directly how it works instead of talking about "what would happen if the geological cycle stopped working".

This is textbook stuff, and needs to be said, however I'm no expert on geology, someone more experienced should review this and improve this section. If you are a geologist please in the spirit of Wikipedia "Be bold" and dive in and edit it further :) Robert Walker (talk)

When something is clearly lacking like this then you don't need to be an expert on the subject to add it in as a "stub" as I did. But it's good to add a few citations to the published work on the subject as otherwise it can be easy for other editors to think it is of no substance and delete it with just a remark in the history log - as happened with part of my contribution here the other day (now fixed by rephrasing it and adding a citation). In a situation like my second para. here the other day, they should add a request for citations or for expansion, or rephrasing and clarification, rather than just delete it. But if they don't know the subject that well, it can be hard to distinguish contributions without references from the many completely unsupported additions to the wiki so it's good to add some citations to make it easier for those who patrol for the addition of nonsense and speculation to wikipedia.Robert Walker (talk)

Total atmospheric CO2

I have also flagged this up on a page that references your figure of 810 e9 tonnes. My problem is that dividing this figure by the accepted (and easily verified) mass of the atmosphere of 5 e15 tonnes you get 162 ppm by mass of CO2 or 106ppmv of CO2 which is in contrast to the currently accepted figure of 380ppmv. Could you please explain the discrepancy? Colin Mill 09:26, 3 November 2006 (UTC)

The image in the article shows 750e9. Significant discrepancies are to be expected in this field. The discrepancy with 810e9 is less than your 300% ppmv difference. You did not explain your mass-to-volume calculation. Maybe you're using the volume of the atmosphere without compensating for decreasing density with altitude? (SEWilco 19:57, 3 November 2006 (UTC))

The total mass of the atmosphere can readily be calculated from sea-level pressure which is equal to the weight of gas overlying unit area (10 tonnes/sq.m) and the total area of the earth (5.1e14 sq.m). The following reference shows a number of sources that agree closely with this figure of 5 e15tonnes = 5 e18kg:-

http://hypertextbook.com/facts/1999/LouiseLiu.shtml

The commonly quoted current concentration of CO2 in the atmosphere is 380 ppm by volume (see:-http://www.noaanews.noaa.gov/stories2005/s2412.htm). Because CO2 is more dense than air (stp density of CO2= 1.977 kg m-2, stp density of air = 1.293) means that by weight this proportion becomes 380 x 1.977/1.273 = 590 ppm by weight (this is in reasonable agreement with http://en.wikipedia.org/wiki/Earth's_atmosphere). If you multiply the total mass of the atmosphere by this proportion you get a mass of CO2 in the atmosphere of 2,950 e9 tonnes. Colin Mill 22:50, 3 November 2006 (UTC)

Try this: convert mass of atmosphere into moles (at 78% N2, 21% O2, 1% other [example argon]), that is 5e+15 tonnes made of gas at 0.78*28 g/mole + 0.21*32 g/mole + 0.01*40 g/mole = 1.73e+20 moles gas in atmosphere. 750 Gt carbon = (750e+9 tonnes * 1e+6 grams/tonne / 12 g/mole C) = 6.25e+16 moles C in atmosphere. Molar concentration = volume concentration in a gas; 6.25e+16/1.73e+20 = 0.000362 = 362 ppm @ 750 Gt. Recalculate for assumed 810 Gt C in atmosphere -> = 391 ppm. Where I think you got in trouble before was that you were calculating mass C/mass atmosphere, not mass CO2/mass atmosphere and not volume CO2/volume atmosphere (correct approach for "ppmv"). Cheers, T. MacKenzie PhD. — Preceding unsigned comment added by 131.202.153.0 (talk) 14:38, 21 February 2012 (UTC)

I found out that there is approximately .035% carbon in the atmoshere on a molar basis. -Universiy of Michigan

I calculated the amount of carbon in the atmosphere and got 2,730.8 Gigatons. I got the mass of the atmosphere from the Handbook of Chemistry and Physics. I calculated the mass percent of carbon in the atmosphere and multiplied the two numbers.

I found out that 9 million metric tons of carbon dioxide were produced during cement production in 1993. -Energy Information Administration

I found out that 100 million tons of carbon dioxide are emitted into the atmosphere each year from cement production. -Greenhouse Gas Online

Carbon dioxide emissions from cement production are estimated at 560 million tons per year. -Information Unit on Climate Change

The amount of CO2 absorbed during the curing of concrete seems to have been neglected in this article unless the figures quoted are net values. CO2 absorbtion occurs when cement is used to make concrete. Absorption occurs rapidly during the cystalisation phase of the curing process, but also for some time afterwards. —Preceding unsigned comment added by 120.17.95.38 (talk) 04:27, 8 May 2009 (UTC)

Interesting facts:cement prodution is the third largest cause of man-made carbon dioxide emissions. While fossil combustion and deforestation produce a significantly larger amount of carbon dioxide, cement production accounts for 2.5% of total worldwide emissions from industrial sources. -Information Unit on Climate Change

Sam

Hi Sam - Many thanks indeed. I now see that the problem lies with the other web page:- (http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions) which has taken your figure for carbon in the atmosphere and used it as the figure for carbon dioxide in the atmosphere which accounts for the near factor of 3 difference. OK I'll go to the discussion on that other page and flag their problem up. Colin Mill 11:41, 5 November 2006 (UTC)

Did the other page violate WP:NOR or does it cite a source? Preferably a source which explains its calculation. (SEWilco 18:01, 5 November 2006 (UTC))

No, I think they simply misread the information in this article - I have subsequently found other sites where confusion between mass of carbon and mass of CO2 has occurred. Colin Mill 08:59, 12 January 2007 (UTC)

Here is the current article on the carbon cycle in the ocean with some corrections I made in my environmental science class.

CARBON IN THE OCEANS

The sea contains around 38000 gigatons of carbon, mostly in the form of bicarbonate ion. Inorganic carbon, that is carbon compounds with no carbon-carbon or carbon-hydrogen bonds, is important in its reaction with water. This carbon exchange becomes important in controlling pH in the ocean and can also vary as a source or sink for carbon. Carbon is readily exchanged between the atmosphere and ocean in regions of oceanic upwelling, carbon is released to the atmosphere. Conversely, regions of downwelling transfer carbon (CO_2) from the atmosphere to the ocean. When CO_2

I found something differnt about the amount of CO2 in the atmosphere then Sam. I am also in the environmental science class and am working on the same project:

According to the "Center for Terrestial Ecosystem Carbon" (http://www.oznet.ksu.edu/ctec/Carbon/carboncycle.htm) there was around 578 Gigatones of CO2 in the 1700s. By 1999 there was around 766 Gigatones of CO2. It's estimated that the Gigatones of CO2 increase by 6.1 Gigatones per year. Just thought I'd share. -Adam

I'd double check those figures. The article appears to have been written by students, not peer reviewed, and appears to have a ProAGW slant. It also erroneously states that limestone does not play a role in the overall carbon cycle of the planet, which it clearly does at geologic timescales. —Preceding unsigned comment added by 148.109.58.5 (talk) 21:13, 27 August 2010 (UTC)

A second more accurate diagram

There is a more technical and but accurate diagram at http://science.hq.nasa.gov/oceans/images/global_flows_carbon.gif with better figures: should we use this as well given comments about bad (i.e. old (i.e. circa 2004)) figures in the current diagram? Mattjs 13:42, 30 May 2007 (UTC)

It just dawned upon me also that it might be possible to do a block diagram like this without out using a jpeg but using Wiki functionality etc and therefore be able easily and readily update the figures (and use Gt rather than Pg...) ... ??? Mattjs 13:42, 30 May 2007 (UTC)

• No let's stick with the one we have. Although supposedly less accurate it is of much more use to the average user. It contains more detail (eg about the influence of marine biotia), and it is much easier to see what is going on. It helps the understanding of the subject much more than the other diagram Mike Young 15:31, 30 May 2007 (UTC)

• Sorry, the carbon cycle picture is seriously misleading. For example, it gives an impression that carbon exchange between oceans and atmosphere happens in the same place, geographically, which thus easily justifies a simple subtraction of fluxes and getting a simple difference. In fact, equatorial areas outgas CO2, which then splits somehow between NH and SH, gets transported polarwise, and only then gets sinked back in some isolated areas. The picture clearly needs a correction.Alexei123 01:36, 25 June 2007 (UTC)

Notes and References

I have never seen Notes and References in an article before - shouldn't these be merged together into one References section? 220.240.58.190 14:24, 31 May 2007 (UTC)

The numbers are confusing and my new Ref turned up in the Notes section and the Notes are actually labeled References? 220.240.58.190 14:25, 31 May 2007 (UTC)

Something Fishy?

Thanks for an informative and timely page! However, It states that "Over-fishing will reduce the amount of Marine Biota in the sea and thus decrease the amount of Carbon taken out of the atmosphere by sea creatures and thus be a direct cause of increased atmospheric Carbon Dioxide levels, and consquent global warming" Wouldn't this only be true for autotrophic fish species? (I now know what autotrophic means, because I just read your article!) Wouldn't the kelp wrapper on your sushi be a bigger ecological threat from this point of view than the tuna inside it? Overfishing may be an economic concern, but why does it matter, from an environmental point of view, whether fish are eaten by sharks or starving children? But I'm just kibbitzing, and will leave it to someone else to change it if necessary.

BTW, just how many GtC/yr get taken out of circulation by "sinkers". Is this about equal to the 4 GtC/yr that is passed from marine biota to the deep ocean, or to the 0.2 that makes it to the bottom as sediment? Thanks! HuMcCulloch 18:19, 11 September 2007 (UTC)

It sounds very dubious. I'd take it out unless its sourced William M. Connolley 19:59, 11 September 2007 (UTC)

It was sourced, as it happens, but to an article/essay that self-describes (see it's opening abstract) as a minority viewpoint. The essay contained no scientific support that I could determine (although it does have some cool diagrams!). There's also a whiff of "personal research" about it. The comparison of overfishing to AIDS, for instance, seems a bit of a stretch. Anyway, the upshot is that I judged the source to be unreliable, and so removed the point from the article. Cheers, --Plumbago 08:11, 12 September 2007 (UTC)

Carbon Solubility

In the section titled "In the atmosphere" under the subheading "Carbon can be released back into the atmosphere in many different ways" one of the points is "At the surface of the oceans where the water becomes warmer, dissolved carbon dioxide is released back into the atmosphere."

Isn't it actually where the water becomes COLDER that CO2 is released back into the atmosphere. My understanding of the chemistry is that warmer water can dissolve more CO2. Am I mistaken? Thanks. —Preceding unsigned comment added by 65.222.211.242 (talk) 20:07, 4 August 2008 (UTC)

You are in fact mistaken. Gas solubility in liquids increases as temperature goes down. You may be confused because it is the opposite for solids dissolved in liquids; that is, solid solubility in liquids increases as temperature goes up. 24.211.245.220 (talk) 05:40, 6 September 2008 (UTC)

Anthropogenic global warming can't be taken as pure fact

Although I too believe in the our part in global warming this cannot be given as pure fact, the minimum would be to cite it. as a reference from the article about greenhouse effect:

 "Anthropogenic global warming (AGW), a recent warming of the Earth's lower atmosphere as evidenced by the global mean temperature anomaly trend,[11] is believed to be the result of an "enhanced greenhouse effect" mainly due to human-produced increased concentrations of greenhouse gases in the atmosphere[12] and changes in the use of land.[13]"

And the citation from this article 

 "Other gases containing carbon in the atmosphere are methane and chlorofluorocarbons (the latter is entirely anthropogenic). The overall atmospheric concentration of these greenhouse gases has been increasing in recent decades, contributing to global warming."

If there is a reason to state this as fact, the article on greenhouse effect should be changed, at least for the sake of consistency. —Preceding unsigned comment added by 79.179.11.57 (talk) 01:30, 4 February 2009 (UTC)

Problems with the Carbon Budget page

The figures in the carbon budget page are a mess, and there's a denialist site in the references from which most of those figures are coming from. Someone please check it. —Preceding unsigned comment added by Miguelveraleon (talk • contribs) 19:06, 23 December 2009 (UTC)

Speaking as an oceanographer (though not a carbon cycle specialist), I would say that page should be deleted. As it is now, it's just incoherent babbling. There are some true factoids, but it doesn't really say anything. There's no such thing as THE carbon budget -- there's carbon budgets of the oceans, the biosphere, of stellar interiors, etc. 128.160.199.100 (talk) 21:32, 28 December 2009 (UTC)

this shit suck

Yes, that was my reaction too. I put a db-g1 tag on it just now, it is just as you say: incoherent babbling along with a list of factoids a few of which contain numbers that could be completed to true sentences. The author has no talk page so can't be reached that way. --Vaughan Pratt (talk) 21:23, 2 July 2010 (UTC)

Meanwhile I put a merge-to-this-article tag on carbon budget instead (deletion is wrong given that some people do use the term "carbon budget," more or less synonymously with "carbon cycle.") Intended upshot is to replace the text in carbon budget with a redirect to carbon cycle. Thanks to decltype (talk) for recommending this way of dealing with the article. --Vaughan Pratt (talk) 18:35, 6 July 2010 (UTC)

Figure shows the deep ocean storage is shown as 38.100 GtC

The deep ocean storage in the figure is shown as 38.100 GtC. Should that be 38,100 GtC instead? It seem peculiar to have 3 significant digits to the right of the decimal point and the quantity seems too small. Thanks! --Lbeaumont (talk) 14:42, 19 April 2011 (UTC)

Per the carbon-cycle diagram in the articel (which is from GISS/NASA) and presumably reliable), 38.1 GtC is correct. We don't need the extra 00's though.... Cheers, Pete Tillman (talk) 18:14, 5 August 2011 (UTC)

Carbon cycle: new research on carbon-dioxide cycling

For many years, there have been questions regarding CO2's role in the atmosphere: does increasing CO2 lead directly to global temp increases, or do warmer temperatures increase CO2 emissions from (eg) the oceans? As is well-known, the Antarctic ice-cores show paleo-temp increases leading CO2 increases by (ims) around 400 years, but the current scientific consensus is that CO2 content is the Earth-surface's thermometer.

Prof. Murray Salby , the Chair of Climate at Macquarie University has a new paper in press that argues that "emission of CO2 from natural sources, which accounts for 96 per cent of its overall emission, plays a major role in observed changes of CO2. " Abstract. While it's premature for here (until the paper is actually published and digested), there's an interesting discussion in progress at Judith Curry's, with Curry commenting that "If Salby’s analysis holds up, this could revolutionize AGW science," and other readers noting this has been simmering under the radar for awhile now. Happy reading -- Pete Tillman (talk) 18:01, 5 August 2011 (UTC)

Add current news?

• New research in published this week's Nature Geoscience details a mechanism by which carbon is drawn down from the surface of the Southern Ocean to deeper water below. (France 24) (Phys.org)

from Portal:Current events/2012 July 29 99.181.140.183 (talk) 03:20, 30 July 2012 (UTC)