Talk:Ocean acidification

References

If there's someone who is willing to assist in doing the coding format (not my forte) for the references section, I'll put in some time to citing the material as appropriate. Thanks. Arjuna 00:38, 11 August 2006 (UTC)

Percent Calculation

The figure has been quoted often about the oceans having increased their acidity by 30% Could a short clarification and calculation be added into this article? Does this refer to negative the base-10 log of the concentrations?

If so, I'm clearly using the wrong number or wrong calculation in the following:

Ratio of underlying concentrations would be,

(10^(-8.104)) / (10^(-8.179)) = 10^ = 10^(0.075) = 1.1885 or so, making present day concentrations (just under) 19% higher. Could someone clarify how the "30% higher" is obtained, and, include a section highlighting this oft-quoted figure, in the article?

(I'm starting to think my calculation is correct and the problem is merely that the numbers in the wikipedia article as only as of 1994...if so, more recent numbers really should be used....if not, then again by all means, please post a corrected calculation. Either way, thanks in advance)

Added later: I've found a reference with the answer to my own question: sure enough, unfortunately, the wikipedia entry is quite out of date with the -0.075 figure from 1994; recent number are about -0.11 for the pH change, see http://www.sciencenews.org/articles/20080315/bob10.asp --Harel (talk) 00:52, 16 March 2008 (UTC)

Factors which may mitigate ocean acidification

Projections of ocean acidification are based on the expected buildup of carbon dioxide. However, changing weather patterns could prevent parts of the ocean from becoming more acidic.

Well, we have more than just projections, we've already acidified the ocean to a small degree. As for the projections, the largest uncertainty by some margin is what we are going to do. Scenarios of future CO₂ emissions by necessity rely on a limited understanding of human and economic factors. Regarding weather, the biggest change that will affect acidification is ocean warming itself (already observed). As well as reducing the amount of CO₂ surface waters can hold, warming will tend to stratify the ocean vertically, reducing the quantity of anthro CO₂ that makes it to the deep ocean. While this decreases (temporarily) the acidification of the deep ocean, it increases climate change in the meantime. --Plumbago 12:11, 15 September 2006 (UTC)

>>>>>>>>>>>>> We've got to stop this sloppiness in the terminology. Its NOT ocean acidification. Its the reduction in the alkalinity of the oceans. The thing is if people could "THINK" it wouldn't matter if we used these colloquially sloppy definitions. But people can't think and so definitions are important. This concept is clearly a gyp driven only by this sloppy and misleading terminology. No-one could get excited about a tiny move towards neutrality and non-corrosiveness.

"pH is a measure of the acidity or alkalinity of a solution.

Aqueous solutions at 25 ℃ with a pH less than seven are considered acidic, while those with a pH greater than seven are considered basic (alkaline).

The pH of 7.00 is considered neutral at 25 ℃ because at this pH the concentration of H3O+ approximately equals the concentration of OH− in pure water.”

So sayeth wiki. And we never ought deviate from this clear understanding.

Now it wouldn’t MATTER that we deviated colloquollially. ACIDIFICATION is a word that comes ‘trippingly off the tongue” whereas ALKALINITY might get some tongue-tied.

It wouldn’t matter. But as we have seen there are some people who simply cannot think.

And so if once allowed to call things what they wish then they can play any number of word-games.

Acids below 7. Alkalines or Bases above 7.

Going from 9 to 8 is reducing the alkalinity.

Going from 5 to 4 is increasing the acidity.

Get rid of the sloppy and misleading terminology and you won’t make fools of yourselves getting worried over nothing. This is a war against irrationality and keeping your concepts clear is like keeping your powder dry. But anyhow:

“Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.179 to 8.104 (a change of -0.075)[1][2].”

Gyp or no gyp?

Particularly as we know that some fresh water has been added during that time.

>>>>>>>>>>>>>>>>>>>>>>>>>>>

 —The preceding unsigned comment was added by 122.148.183.191 (talk) 00:14, August 20, 2007 (UTC) 

Please read (and, one would hope, understand) the prior discussion on this talk page before ranting. Arjuna 05:05, 20 August 2007 (UTC)

Some of the world's arid areas may see more precipitation (as is already happening in parts of Australia). This has the potential to reverse acidification of seawater by flushing sodium carbonate (a common substance in desert soils) into the ocean. Another possibility is that man may leach carbonate-rich soils to make them productive for agriculture– again, much of the carbonate would enter the sea.

I don't believe the quantities involved can offset the scale of the CO₂ perturbation. It's not strictly my field, but I've yet to see any acidification study that bothers to include minor second-order effects such as this. In the extreme long term (1000+ years) processes such as this will mop up some of the remaining anthro CO₂, but they're too minor to much offset what we're doing with CO₂. If you think about it for a moment, atmospheric pCO₂ rose for ~2 centuries with very modest emissions and normal rainfall. Now our emissions are massive (let alone future emissions ...), so even doubled rainfall is unlikely to much affect these balancing processes. Admittedly, you're arguing that currently dry areas will become wet, so my doubling is likely an underestimate, but even so I think scale is the problem here. Yes, this may well happen, but magnitude is what matters, and I'm not convinced this will play a significant role. However, it's not my field, so I may be convinced with appropriate sources. --Plumbago 12:11, 15 September 2006 (UTC)

Carbonatite volcanism is another potential source of soluble carbonate. Carbonatites are igneous carbonate rocks which are scattered across continents. One active source of carbonatite is known– the Ol Doinyo Lengai volcano in Tanzania. If others erupt under seawater, their soluble carbonates will raise the pH of waters around them. Tony 09:55, 15 September 2006 (UTC)

Again, scale matters - this is a minor process at best. Furthermore, as this sort of vulcanism has been going on all the time, pre-industrial atmospheric CO₂ (which remained broadly constant since the end of the last ice-age) was presumably in balance with it. So it can't play an important role in the ongoing anthro perturbation (i.e. because it's already accounted for in the natural balance). It'd take new vulcanism to change things, and there's no reason to expect that to happen - we may be a new geological force on the Earth, but even we can't cause vulcanism. Anyway, good points raised, but I doubt they're major processes. Cheers, --Plumbago 12:11, 15 September 2006 (UTC)

Graphs

Graphs. We need graphs dammit. Something like this: http://en.wikipedia.org/wiki/Image:Instrumental_Temperature_Record.png

Something that I can wheatpaste everywhere.

Graphs, dammit! —The preceding unsigned comment was added by 75.73.155.34 (talk) 06:29, 17 December 2006 (UTC).

This preceeding comment was added by ME because I was too lazy to log in--Crucible Guardian 06:31, 17 December 2006 (UTC)

Acidification

An unknown user added the following to the introductory paragraph: "Since a pH of 7 is neutral, below 7 indicates acidity and above 7 indicates alkilinity, the above-mentioned reduction is actually properly defined as reduced alkilinity rather than increased acidity." I reverted these edits, since (in addition to misspellings) it is factually incorrect. One measure of acidity is the concentration of hydrogen ions, and the documented pH reduction in ocean surface waters represents a 30% increase in hydrogen ions. Thus, it is "acidification", even if it is true that the current ocean surface pH still measures on the alkaline side of the scale. Furthermore to the extent that similar concepts are reflected in common language, as researcher Ken Caldeira has noted, a cup of hot tea left on a table is "cooling down", not "becoming less hot". Arjuna 23:43, 3 January 2007 (UTC) (minor revision Arjuna (talk) 01:19, 18 May 2009 (UTC))

Arjuna: I am the unknown user and I acknowledge the typos but the addition was not factually incorrect at all, in fact it reflects standard high-school terminology. I think a short description of the pH scale is important to those unfamiliar with the term. I myself was alarmed at the 'increased acidification' until reading that the pH is still above 8. The tea analogy is not appropriate as one could easily say more neutral rather than more acidic. I added a compromise position based on your own words.

JG17 14:54, 4 January 2007 (UTC)JG17

Sorry, changed it again. I don't think it's the most pertinent place to add this comment about ocean pH. I've moved it lower down in the article, and edited it somewhat (quite a lot actually). The most important part of ocean acidification is not what ocean pH is, but what is happening to it. By prominently mentioning that ocean pH is greater than neutral, I think the previous edit might confuse readers into thinking that just because seawater's on the right side of acid, everything's OK. Furthermore, a discussion of the pH scale is only a single click away, so readers don't necessarily need to be led by the hand. Cheers, --Plumbago 13:28, 4 January 2007 (UTC)

Plumbago: I accept your changes but perhaps not so much the sentiments behind it. I thought well-presented facts were more important than opinions here: This is an encyclopedia, not a propaganda pamphlet and it's best value is in it's neutrality. By one analogy, if you read Franco's revision of Spanish history you will discover that, far from decimating indiginous populations in the bloodthirsty pursuit of gold, the conquistadors apparently brought civilisation, education and much-needed religion to the savages. JG17 14:52, 15 January 2007 (UTC) 4-1-2007 —The preceding unsigned comment was added by User:90.20.203.67 (talk • contribs).

Erm, sorry, I don't follow. The change I made was entirely factual and neutral. I moved the statement about what the ocean's pH is into the main body of the article as it's unnecessary for the opening paragraph. The actual pH value of the ocean is, more or less, secondary in the article to hand. What's significant is that it's changing (hence the article on acidification as a process). My concern was that this significance would be lost to a non-specialist reader were the pH of seawater to be arbitrarily compared to freshwater. Whether seawater is acid or alkaline has little bearing on acidification; adding CO₂ to it will acidify it. And I don't quite see what Franco has to do with carbonate chemistry I'm afraid. Cheers, --Plumbago 14:58, 4 January 2007 (UTC)

Plumbago: I did say I accepted the change. It was just your stated concern (here) on what readers may think that I discussed. I had exactly the same concern, but I agree the final statement is perfectly neutral. The Franco reference was about the preference of policy to facts but I admit it was over the top. Mind you, I don't know what cooling tea has to do with chemistry either. Nice talking to you. JG17 14:52, 15 January 2007 (UTC)JG17 JG 4 January 2007

Thanks Plumbago, I think your edits (and comments) got it spot on. As I explained, one measure of acidity (there are many) is the concentration of hydrogen ions, which is precisely what is happening, and so use of the term is perfectly accurate in a university, research, or indeed even a high school setting. So JG's first addition about what was a proper definition was inaccurate. His comments about "propaganda" or Franco don't quite follow either. If he was alarmed about this issue until he found out that seawater is still above 7 pH, "but not afterwards", then I respectfully suggest that his appreciation of the issue would benefit greatly from reading any of the several excellent reports listed in the "further readings" section. Finally, there is a very good discussion about this (definitional) issue at http://www.realclimate.org/index.php?p=169, and which supports the terms used in the article here. Aloha. Arjuna 19:33, 4 January 2007 (UTC)

Arjuna: I did not say that the other definition is inaccurate. I consider only that the article was previously misleading in that some may understand that the sea is acidic but the sea is actually still alkaline by the standard definition of the pH scale which we all learnt in high school. The entire article reads as if it we were dealing with an 'acid sea' rather invoking the 'acid rain' problem. I do appreciate the concerns about reduced pH though I'd respectfully suggest to you that there are far more urgent environmental concerns about the health of the sea resulting from massive pollution. JG17 14:51, 15 January 2007 (UTC)

JG, since the article clearly states that the issue is the change in pH and level of acidity (again, measured by the concentration of hydrogen ions), rather than whether ocean pH is still above 7.0, it's unclear exactly who would feel misled other than someone who hasn't a basic grasp of chemistry. I encourage you to read the scientific papers and articles cited before belaboring this point any further. Thanks for your opinion as to whether there are far more urgent environmental concerns than OA. You are certainly entitled to hold it– and will be in good company, being consistent with the Bush Administration's current position on the status of CO₂ as a non-pollutant, which as you know is the subject of no small amount of debate at present: http://en.wikipedia.org/wiki/Pollution. There is still much scientific uncertainty as to how organisms and ecosystems will respond or adapt to the increased acidity/pH change, and this is in fact something OA researchers are targeting for the next stage of research. However, the prima fascie evidence is not encouraging. Arjuna 22:10, 15 January 2007 (UTC)

Yesterday I added the following paragraph near the beginning of the article:

Although the term "acidification" is used, it should be borne in mind that the oceans are not acidic (pH less than 7) and are not expected to become acidic. The term "acidity" usually means either how strong an acid is or how much acid a solution contains (per unit volume for example, see Titration). Since one must add acid to ocean water to reach pH 7, one could say that the acidity of the oceans is actually negative. In the context of ocean "acidification", the term "acidity" is often used (incorrectly) to mean hydrogen ion concentration.

"Squiddy" reverted this on grounds that it is original research! I am putting it back in. It is certainly not original research -- it is elementary chemistry. Eric Kvaalen (talk) 14:40, 15 April 2011 (UTC)

It certainly is original research, as defined by Wikipedia. Please provide a source. I don't doubt that sources exist. — Arthur Rubin (talk) 16:53, 15 April 2011 (UTC)

Reposting my comment from Jan07 as applicable here to EK's edit: it is factually incorrect. One measure of acidity is the concentration of hydrogen ions, and the documented pH reduction in ocean surface waters represents a 30% increase in hydrogen ions. Thus, it is "acidification", even if it is true that the current ocean surface pH still measures on the alkaline side of the scale. Furthermore to the extent that similar concepts are reflected in common language, as researcher Ken Caldeira has noted, a cup of hot tea left on a table is "cooling down", not "becoming less hot". Arjuna (talk) 00:50, 16 April 2011 (UTC)

Past and present pH level

The article refers to Jacobson 2005, who estimates pH level for 1751 to be 8.25, while present-day level is supposed to be 8.14. However, NSF, NOAA und USGS (2006): Impacts of Ocean Acidification on Coral Reefs and Other Marine Calcifiers: A Guide for Future Research (PDF, 9,9 MB), p. 4, gives different numbers. There preindustrial pH is supposed to have been 8.16, while today's level is 8.05. Both figures show a decrease of 0.11 points - but which one is correct?? Hardern 15:23, 12 April 2007 (UTC)

Hi Hardern. Good question. I think it probably has to do with the different definitions people use of pH. It's not something I'm an expert on (not least because I don't want to know any more about carbonate chemistry!), but as I understand it, there are (at least) three different pH scales in use today. The free scale (sometimes denoted pH_F), the total scale (sometimes denoted pH_T) and the seawater scale (sometimes denoted pH_SWS). Having just consulted a textbook on the subject (Zeebe & Wolf-Gladrow, 2001, CO₂ in seawater: equilibrium, kinetics, isotopes, Elsevier, Amsterdam, Netherlands) it transpires that these are ~0.1 units apart (with pH_F being ~0.1 units greater than pH_T and pH_SWS). I guess that Jacobson (2005) is using the free scale while your NSF document is using the seawater scale (at least, that's what Figure 1-1's caption implies; though it uses the pH_T notation). However, I say this with only a very limited grasp of carbonate chemistry (just enough for me to get by on), so please feel free to consult wider. It's certainly annoying that pH turns out not to be as simple as the definition in its article suggests! Anyway, hope this helps. Cheers, --Plumbago 15:56, 12 April 2007 (UTC)

Yes, it helps. Thanks for yout investigation. Do you have any recommendation to which one of the three scales should be used in the case of ocean acidification? Hardern 20:32, 12 April 2007 (UTC)

Erm, no. As I understand it, all three scales are still used by scientists (each has advantages and disadvantages). Consulting my textbook again, they differ in how they handle (or calculate) the importance of ionic species such as sulphate and fluoride. The textbook gives equations to convert between them, but they're not simple to use here. My suggestion would be that we (probably me) expand the pH article to describe the different scales (or at least mention that they exist), and then make sure that articles such as ocean acidification are explicit in stating which scales are used whenever pH values are cited. As I've said already, while I do use pH in my own work (which deals with carbonate chemistry), I'm trying to know only the bare minimum about it, so this won't happen overnight!  ;-) Cheers, --Plumbago 08:30, 13 April 2007 (UTC)

I left them a note. Hardern 12:01, 13 April 2007 (UTC)

For me as a chemist it is very amusing to read that there ought to be more than one pH value, since the pH is defined based on the the concentration of H+ in a solution - and there is just one species of H+ in aqueous solutions. H+ can not remember from which kind of acid or base it is coming from, nor does it behave different then. Could you please provide some more detail information about the definition of the "other" pH values? From a chemical point of view it makes no sense to define and use different definition of the pH value than the international standard one.– ghw 06:12, 14 April 2007 (UTC)

As a non-chemist, my understanding is that the different pH scales in use in oceanography have methodological roots. It being the weekend, I don't have my textbook to hand, but I think the simple definition (called pH_highschool in Zeebe & Wolf-Gladrow, 2001) comes unstuck in seawater with its multitude of ionic species. To work out the concentration of H⁺, these other ions need to be accounted for, and that's apparently where the fun begins. Anyway, as there's a little bit more interest now, I'll try to add something about this next week. Maybe put it here first before altering the pH article? I'd be very grateful if you could check over whatever I write since, as I keep banging on, I'm no chemist. Cheers, --Plumbago 06:37, 14 April 2007 (UTC)

ghw, it has to do with the ionic strength and composition of the reference buffer solutions. Page 540 of the article you linked to mentions the existence of special pH scales for blood and seawater. --Itub 16:22, 17 April 2007 (UTC)

An excellent reference... [1] Piyrwq 00:40, 16 April 2007 (UTC)

Good shout. A bit terse however. I've now had a bit of a read of reference 3 below, and have summarised its presentation of the different pH scales as ...

Seawater

In chemical oceanography pH measurement is complicated by the chemical properties of seawater, and several distinct pH scales exist.

As part of its operational definition of the pH scale, the IUPAC define a series of buffer solutions across a range of pH values (often denoted with NBS or NIST designation). These solutions have a relatively low ionic strength (~0.1) compared to that of seawater (~0.7), and consequently are not recommended for use in characterising the pH of seawater (since the ionic strength differences cause changes in electrode potential). To resolve this problem an alternative series of buffers based on artificial seawater was developed. This new series resolves the problem of ionic strength differences between samples and the buffers, and the new pH scale is the referred to as the total scale, often denoted as pH_T.

The total scale was defined using a medium containing sulphate ions. These ions experience protonation, H⁺ + SO₄^2-

⇌ HSO₄^-, such that the total scale includes the effect of both protons ("free" hydrogen ions) and hydrogen sulphate ions:

[H⁺]_T = [H⁺]_F + [HSO₄^-]

An alternative scale, the free scale, often denoted pH_F, omits this consideration and focuses solely on [H⁺]_F, in principle making it a simpler representation of hydrogen ion concentration. Analytically, only [H⁺]_T can be determined, so [H⁺]_F must be estimated using the [SO₄^2-] and the stability constant of HSO₄^-, K_S^*:

[H⁺]_F = [H⁺]_T - [HSO₄^-] = [H⁺]_T ( 1 + [SO₄^2-] / K_S^* )^-1

However, it is difficult to estimate K_S^* in seawater, limiting the utility of the otherwise more straightforward free scale.

Another scale, known as the seawater scale, often denoted pH_SWS, takes account of a further protonation relationship between hydrogen ions and fluoride ions, H⁺ + F^-

⇌ HF. Adding this subtlety changes the concentration of H⁺_T to:

[H⁺]_T = [H⁺]_F + [HSO₄^-] + [HF]

However, the advantage of considering this additional complexity is dependent upon the abundance of fluoride in the medium. In seawater, for instance, sulphate ions occur at much greater concentrations (> 400 times) than those of flouride. Consequently, for most practical purposes, the difference between the total and seawater scales is very small.

The following three equations summarise the three scales of pH:

pH_F = - log [H⁺]_F

pH_T = - log ( [H⁺]_F + [HSO₄^-] ) = - log [H⁺]_T

pH_SWS = - log ( [H⁺]_F + [HSO₄^-] + [HF] ) = - log [H⁺]_SWS

In practical terms, the three seawater pH scales differ in their values by up to 0.12 pH units, differences that are much larger that the accuracy of pH measurements typically required (particularly in relation to the ocean's carbonate system). Since it omits consideration of sulphate and fluoride ions, the free scale is significantly different from both the total and seawater scales. Because of the relative unimportance of the fluoride ion, the total and seawater scales differ only very slightly.

---

Anyway, how's this look? I'd be very grateful for comments, especially from chemists. I'm suggesting we add this to the article on pH, but make sure that this article's pH values are correctly identified with respect to the scale they're using. Cheers, --Plumbago 13:25, 17 April 2007 (UTC)

It looks pretty good. I made one small change to the text above and renamed sulfate to hydrogen sulfate. One minor style issue is that LaTeX is generally frowned upon in chemistry articles for representing simple inline formulas like HSO₄⁻, because they tend to turn into images that don't match the text well. Finally, one thing that would be good to add is what are the typical differences between the scales in practice. One reference I saw, but which I can't seem to find again, gave numbers like "the pH value in the ____ scale is usually higher than in the ____ scale by about 0.08 pH units". This will help put things into perspective; it explains why many (most?) chemists who, unlike oceanographers, only care about pH with a precision of 0.1 pH units (or even 1.0 pH unit!), are surprised to hear that there is more than one pH scale. --Itub 08:51, 18 April 2007 (UTC)

Added two minutes later: the differences I mentioned were in the link given by Piyrwq: [2] --Itub 08:54, 18 April 2007 (UTC)

Hi Itub. Thanks for reading my text! On the LaTeX point, I did originally write the terms in the way you've now edited them. But I changed them as they then looked odd and not obviously related the same terms in the full equations. It may be frowned upon (and I completely understand why), but to me it makes the text less comprehensible when the appearance of terms changes. But I'm OK about conceding this point.

As regards the difference in the scales, you're absolutely correct - I should have put something in about that. I'll do this later. Reference 1 above (formerly 3; I repositioned it) quotes a slightly different figure (possibly a max. difference) and discusses it a bit. I'll get onto this today. Anyway, thanks again for taking the time to look through my text. Cheers, --Plumbago 09:03, 18 April 2007 (UTC)

Just made a couple of further edits to enumerate the difference in values between the scales. I hope that clears things up. I've also "roman-ised" the font of the equations, etc. I'd only done that in places before, but had meant to do it everywhere. Cheers, --Plumbago 12:35, 18 April 2007 (UTC)

OK. I've rewritten the equations and terms above so that they're all non-LaTeX. I think this solves the style issue nicely. YMMV. Cheers, --Plumbago 08:09, 19 April 2007 (UTC)

It looks perfect to me, go ahead. :) --Itub 08:26, 19 April 2007 (UTC)

Done and dusted. I've also put a note on the talk page there. We should probably move future discussion there from now on. Thanks again Itub for taking the time to read my text. As an aside, it's actually been useful to me to have to go through my textbook and work out the seawater pH story. Cheers, --Plumbago 08:56, 19 April 2007 (UTC)

Great job, thanks! That's somehow the problem I wanted to point at: within "stong solutions" the pH is not direct comparable to that what we learn about pH in school. And the next important thing is: a different pH scale is not direct comparable to the standard pH scale, because they differ non-linear "up to" a certain value.– ghw 12:37, 20 April 2007 (UTC)

Poor article

It's a bit poor article, a huge talke here about the meaning of pH Doesn't improve the article.

The article sohuld be more structured, and primairly focus on the risk of this. Because that's what people are trying to warn others of when talking about this. This is not verry wel reflected in the article. It's not about a dispute about pH there is a [wiki link for that topic] should be offtopic here.

When algea can no longer survive as a result of acidification, we get dead zones in the sea Those where allready in the news last year. The sea can realy starve without oxygen, well that is some species anaerobic bacteria can service it, they produce [[ http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc01/icsc0165.htm hydrogensulfate]] This happened the last time when earth's seas died (during perm), as a not so small side effect about 90% of land based live also died in that period. It's about going to happen again soon. One of the greatest mass extinctions in Earth's history occurred at the end of the Cretaceous era, sixty-five million years ago and is believed to be caused by sea acidification

Note this topic is also closely related to melting polar icecaps, known to be the engine of sea water transport trough various oceans, this water system transports the oxygen troughout the ocean. It's that which is required to keep marine life a live.

82.217.143.153 (talk) 23:06, 11 March 2008 (UTC)

Sorry, but I'm afraid I'm going to disagree (though, given I wrote most of the article, that's probably not a surprise). Firstly, the content of the talk page (your complaint about the pH discussion) is neither here nor there - talk pages serve to discuss improvements, and in this case the improvement discussed here was actually made to the pH article in the end. Secondly, the article discusses the known risks of acidification, which primarily boil down to disruption to calcifier communities (corals, coccolithophorids, pterpods, etc.). Ocean dead zones are not directly connected to acidification at all - as the article on the subject describes, they are related to depletion of dissolved oxygen. Nor is acidification directly connected to the loss of polar ice caps - these are separate problems [*]. Anyway, I hope this clears up some of the difficulties that you have with this article, but if you have any others, please just raise them here. Cheers, --Plumbago (talk) 08:43, 9 April 2008 (UTC)

[*] Though there is an interesting connection. Climate change (which causes polar icecap loss) is primarily a consequence of CO₂ in the atmosphere, while acidification is a consequence of CO₂ in the ocean. An increase in one problem is offset by a decrease in the other problem. As time passes the balance of the two problems is gradually shifting from climate change to ocean acidification as CO₂ is absorbed by the ocean.

I actually just came to this talk page to say what a good article this one is. Especially the external links section. A good collection of reliable sources. Charbono (talk) 12:30, 31 May 2011 (UTC)

Coccolithophore rewrite

Hi, I've been keeping half an eye on your re-write and have to say, you've done an incredibly good job. If anything, perhaps the bias has gone a bit further to the "bad news" side than I'd like - but then I guess that's mainly because the "good news" scenario is more appealing to my optimistic tendencies! My one comment would be that the last two sections of the paragraph are still written as if the "bad news scenario" was true - it perhaps needs to be clearer that the decreased CO₂ burial is due to shoaling of the lysocline (if that is what the paragraph's referring to), because the coccolith weight-gain data seems to suggest the opposite. Further, the paragraph

There is also a suggestion that the effect of acidification on coccolithophores may have secondary effects on climate change, by decreasing the earth's albedo via their effects on oceanic cloud cover

doesn't make it clear which effect it's referring to - if abundance has risen, as per the science report, the sense of the sentence needs inverting.

Hope that's helpful, and thanks again for your great work on the article! Verisimilus T 11:08, 24 April 2008 (UTC)

A Sea Change

I am typically the first to revert linkspam, but I'm not sure I agree with Brusegadi's revert of the link to the documentary film (in making) A Sea Change. For the record, I have no connection with the filmmakers. But I checked out the site, and it is not only legit, but rather science-y and looks quite relevant. Plumbago and others, your thoughts? Aloha, Arjuna (talk) 05:50, 11 June 2008 (UTC)

If it helps, I only watched the trailer and I thought that was all that was there. I just noticed that there is also a blog. I will re-add it with a link to the blog and then people can check out the documentary by navigating. I bookmarked it anyways! Brusegadi (talk) 05:58, 11 June 2008 (UTC)

Seems like a good solution... Thanks for taking another look. Cheers, Arjuna (talk) 10:17, 11 June 2008 (UTC)

Link to ocean acidification blog?

I have tried to add an external link to the ocean acidification information outlet. This edit has been automatically reversed. Is there a way to make this addition, assuming that it is an appropriate one? Nuluru (talk) 04:41, 2 July 2008 (UTC)

I think it may be because you weren't logged in when you made the edit, which made it look suspicious to the bot. I reverted to your last edit, not to have that as the final say, but to let the other editors have a chance to see and evaluate. Cheers, Arjuna (talk) 07:36, 2 July 2008 (UTC)

I've just removed this link - it's already included in the article (for reference, this is the second time that I've removed this duplicated link). I've made a further edit to the existing link to try to make this clearer (i.e. I've added the name of the blog's originator). Cheers, --Plumbago (talk) 08:20, 2 July 2008 (UTC)

The bigger picture

In the early history of the earth all the carbon that is here now was in the form of carbon dioxide and/or graphite. There was no organic carbon. The first organism capable of converting carbon dioxide to organic carbonate appeared in late pre-Cambrian times more than 600 million years ago. Organic marine carbonate, mainly limestones, have been deposited in every geological age since then, upto and including the present day. The major coal deposits of carboniferous times took a vast amount of carbon dioxide out of the atmosphere as did the vast limestone deposits of Cretaceous times (chalk) as did the oil and gas resources of primarily Tertiary age. It is elementary logic to conclude that the tenor of carbon dioxide in the atmosphere has fallen steadily from late pre-Cambrian time to the present day. It is obvious that the limestones (shell beds) have not been dissolved by acid oceans for they are there for us to see today despite the much higher tenor of carbon dioxide in the atmosphere in earlier times. Disregarding the present miniscule increase in the proportion of carbon dioxide in the atmosphere and the fluctuations during glacial and interglacials it is probably fair to say the the tenor of carbon dioxide in the atmosphere is as low as it has ever been in the history of this earth. In short the geological evidence indicates that the system is strongly buffered and has been so throughout geological time and that marine organisms are well adapted to the small range of pH that exists from place to place in the oceans.

Roger Dewhurst (talk) 20:42, 16 December 2008 (UTC)

You had me up and until "miniscule", after that point your comment goes down-hill. First you need to reconcile timescales (are you talking evolutionary, geological or human timescales). Even on the geological timescale the current amount (380+ppm) is high (iirc we have to go back 10+ millions of years to find equivalent), although the timespan of it is short.

Your geological evidence gets out of sync with current times, because the increase isn't natural. And that it says little to nothing about the evolutionary timescale of the marine creatures. It doesn't tell us much that there where critters who thrived in high CO2/acidic atmos/oceans, when its not the same critters as are here today. But even considering these - you seem to have overlooked the PETM. Where a large increase in carbon (similar to what is happening now) had tremendous impact on the wellbeing of marine biology. And why exactly should we disregard the current increase? -Kim D. Petersen (talk) 21:27, 16 December 2008 (UTC)

I appreciate that there was some ambiguity there. 'Miniscule' in terms of the absolute amount of carbon dioxide rather than the relative amount of carbon dioxide. I am certainly not talking of human time scales. I feel that it is this general inclination to think in terms of human timescale that is a principle cause of misunderstanding. If we go back 10 million years,and I do not think we have to go back quite that far, we are back in a period when our early ancestors were around and the ancestors of all extant mammals pretty closely resembled what is around today. I might note in passing that there are brachiopods living today which closely resemble the brachiopods of lower Palaeozoic times. The genus Mytilus, which you can buy in your local supermarket, or you can if you live in New Zealand, was around in Triassic times if my memory serves me correctly. Roger Dewhurst (talk) 01:37, 17 December 2008 (UTC)

That single genus' exist now, as they did then is not the question here. What is of interest is specific species. Adaptation takes time - and here we are talking about evolutionary timescales. Ie. The crocodile and the shark have been around for hundreds of millions of years, while other species and genus' have died out, or evolved. When reflecting on this, we both need to reflect on things on a short timescale, as well as on the longer timescales. --Kim D. Petersen (talk) 01:58, 17 December 2008 (UTC)

Small addendum: What is interesting here, and for the article, is the specific scientific assessments (see: WP:RS) of the issue, and the relative weight of these. (see: WP:WEIGHT). We (you and i) can agree or disagree as much as we want, in the end its what the reliable sources say that matters. --Kim D. Petersen (talk) 02:16, 17 December 2008 (UTC)

I suppose that I am predisposed to look at forest rather than the trees. —Preceding unsigned comment added by Roger Dewhurst (talk • contribs) 03:10, 17 December 2008 (UTC)

I can't say that i disagree - but singling out a specific genus as an example, instead of looking at the larger picture. Is looking at a tree, and not a forest. What i mean about specific species, is that a genus has a variation of species (and possibly subgenii), and when looking at large short term changes, its on the species level (and not on the genii) effects will be felt. Its timescales again. --Kim D. Petersen (talk) 03:24, 17 December 2008 (UTC)

There is the sentence,

"While the full ecological consequences of these changes in calcification are still uncertain, it appears likely that many calcifying species will be adversely affected."

-- which immediately follows recent references showing that there is no adverse effect on the coccolithophores and corals studied. So at the very least, that sentence should have a current reference.

Another point that is not emphasized in the article is that "average ocean pH" is a construct which, like "average global surface temperature", is subject to many qualifications; for example, in the Pacific Warm Pool it is not at all unusual for the pH of water sloshing around an atoll to vary by four or five pH points (e.g. 8.4 -- 7.9) over a 24-hr period. -- Craig Goodrich 206.39.12.241 (talk) 13:51, 22 June 2010 (UTC)

On your first point, the article lists a number of references that show negative, ambiguous and positive effects on in the response of calcifiers to elevated DIC. That there are known negative effects for some of the studied species is why it concludes "it appears likely that many calcifying species will be adversely affected". It could say "some calcifying species", but I don't think it's well quantified at this time. I suggest amending the article to reference the Royal Society report at this point since I believe it makes this similar point (in fact, I should have done this before - I think I'm responsible for the offending sentence).

On your second point, some statement could be inserted to note what you say, but it would help if there's a reference to support it. Have you got one to hand? However, this should be done carefully so that it doesn't give the impression that just because pH varies locally by some big number of units, some global decrease by a smaller number of units is of limited importance (cf. the same is true for temperature). Cheers, PLUMBAGO 16:49, 22 June 2010 (UTC)

Images

I've uploaded to WikiMedia an example image of a NOAA/PMEL ocean acidification buoy, deployed by PMEL, NOAA/AOML, NOAA/NESDIS and the University of Puerto Rico. The file is Oa-buoy-enrique-reef.jpg and the link to it is http://commons.wikimedia.org/wiki/File:Oa-buoy-enrique-reef.jpg, in case anybody wants to add to the current narrative. There is also a blog of our deployment of the instrumentation at http://atlantic-mcb.blogspot.com/ in case you'd like a little more context. You may also write to me at jim dot hendee zat noaa dot gov if you'd like more info. I'm still a neophyte Wiki user, so be my guest until/if I figure out how to add it appropriately. Sharkface (talk) 17:39, 19 January 2009 (UTC)

Sure, I could add that photo. Maybe it would be best for you to add some text first, and I'll clean the text (if needed) put the photo in the text. That way there's some better context. Mailseth (talk) 20:54, 19 January 2009 (UTC)

I've gone ahead and added that image and another under gallery, but will (after conferring with colleagues) later add some relevant narrative to include as a special section on instrumental considerations. Hope that works! Sharkface (talk) 12:20, 20 January 2009 (UTC)

Biochar

I'm removing the text on biochar to here for the time being. I can't find anything about this in any reliable source on a Google trawl or on the Web of Knowledge, and it doesn't sound all that plausible an idea in the first place. There are vague suggestions in the scientific literature about adding basic minerals to the oceans to combat acidification, but this is the first time I've heard anyone suggesting biochar. However, if it can be sourced to something reliable, just add it back in. Cheers, --PLUMBAGO 07:28, 19 May 2009 (UTC)

Possible solutions to the problem

The addition of charcoal, also known as biochar, directly to the oceans would have the effect of absorbing acids and raising the pH. It would also have the effect of locking up carbon derived from organic matter which would otherwise rot down, releasing CO2 back into the atmosphere. The addition of charcoal to agricultural or forestry soils has the same effect, thereby reducing the acidity of water running off the land into rivers and ultimately into the oceans.

Plumbago, I agree with you completely. Seems, at the very least, to be lacking in context, and probably WP:OR. In principle a magic bullet would be nice though! Cheers, Arjuna (talk) 20:29, 19 May 2009 (UTC)

Question

Quote: "Ocean acidification is the name given to the ongoing decrease in the pH of the Earth's oceans, caused by their uptake of anthropogenic carbon dioxide from the atmosphere". How can one distinguish anthropogenic carbon dioxide from any other carbon dioxide? Does it carry a label? Biscuittin (talk) 18:28, 9 February 2010 (UTC)

I have removed "Anthropogenic". Biscuittin (talk) 15:42, 11 February 2010 (UTC)

It has been (rightly) restored. Because the CO2 level of the atmosphere has been broadly constant since the end of the last ice age (10 kya), is it assumed (on good grounds) that, prior to the current industrial period, the ocean and atmosphere were broadly in equilibrium with one another (i.e. net zero exchange). As such, the addition of CO2 to the atmosphere by anthropogenic processes has led to an increase in oceanic CO2. As you correctly note, this cannot be chemically distinguished from "natural" CO2 (although the radiocarbon signature of the ocean provides one hint), but it can be inferred and there are a number of techniques for this. The quantity of anthropogenic CO2 in the ocean can additionally be estimated from carbon cycle models which explicitly simulate the anthropogenic transient in atmospheric CO2 (albeit with a number of caveats). Does this help? --PLUMBAGO 16:46, 11 February 2010 (UTC)

I still think it is misleading to use the word "anthropogenic" without qualification because the additional CO2 is probably a mixture of anthropogenic and non-anthropogenic. Biscuittin (talk) 17:43, 11 February 2010 (UTC)

It is incorrect to view it as a mixture. The "excess" CO2 that is acidifying the ocean stems from anthropogenic activity. It is not from natural background CO2. Natural CO2 is not (significantly) changing in concentration in either the ocean or atmosphere, so the changes to the ocean that are occurring are anthropogenic in origin. Unless, that is, you have cause to believe that anthropogenic CO2 is somehow mysteriously remaining the the atmosphere while natural CO2 is solely acidifying the ocean.

I think you're probably getting confused by the fact that the natural carbon cycle is dynamic, such that there are fluxes of CO2 both into and out of the ocean. Since the natural carbon cycle is believed to have been broadly in equilibrium prior to the industrial period, these fluxes were balanced and the ocean's pH unchanging. By increasing the atmospheric concentration of CO2, human activities have shifted the balance such that CO2 now has a net flux into the ocean, which is causing acidification.

Sorry if I'm not explaining this to your satisfaction. Cheers, --PLUMBAGO 19:53, 11 February 2010 (UTC)

There is simply no evidence that the ubiquitous carbon cycle, producing merely superficial and temporary parochial changes in isolated areas of surface ocean alkalinity and easily and fully dissipated back into the atmosphere by mere wind/wave agitation has any significant unnatural impact whatsoever upon the topic, phenomenon nor subject of so-called "Ocean acidification" (derived from the Acid Rain root) . Sulphuric and Nitric Acids produced primarily from the anthropogenic growth explosion of non catalyst equipped petroleum burning power plants (engines) that are heavier, non degrading and persistent in oceanic aquifers is by far the most serious and actual real problem. This CO2-Mass-Hysteria carbon derivative trading industry propaganda in this article makes it both grossly erroneous and totally misleading.Urlborg (talk) 15:05, 28 June 2010 (UTC)

Thanks for sharing. Could you provide some reliable sources to improve the article with these views? The article already contains reference to quite a number of scientific studies and reviews that seem to suggest that ocean acidification is (a) CO2-related, and (b) a potentially serious problem. If the article is misrepresenting scientific opinion on this topic, let's sort it out. Cheers, --PLUMBAGO 16:45, 28 June 2010 (UTC)

Acidification section: updating and improving the chart

I commend the inclusion of the chart in the Acidification section since it gives a quick-glance summary. At the same time, the chart is problematic in several respects:

1. First, it is out of date, regarding the acidification that has already (to date) taken place so far. The most recent figure it gives vis a vis changes since the outset of the industrial revolution, is a pH decrease of 0.075, while the article cites a larger pH change, of "just under 0.1" from more recent figures. In fact, even that is a bit out of date: the most recent summarized I have found indicate a pH change (comparing the outset of the industrial revolution to "today" where "today" refers, depending on the source, to the last half dozen or fewer years. Source include:

a. College of Earth, Ocean, and Environment University of Delaware, Newark, DE which runs http://www.scor-int.org/ by the Internatioanl Council for Science's Scientific Committee on Ocean Research (SCOR), where at www.scor-int.org/OBO2009/A&O_Report.pdf it is stated: "Indeed this process of ocean acidification has reduced the surface ocean pH by about 0.11 already (a change of about 30% in hydrogen ion concentration)" in a Sept 2009 statement made in Venice at SCOR's Biological Observatories Workshop in a report of the Ocean Acidification and Oxygen Working Group (incidentally, taking their Figure 2's linear trend line would give about 8.07 in 2005, or 28.5% (29% to the nearest whole) more acidified than pre-industrial, by 2005)

b. From the Australian Antarctic Division, a division of the Department of the Environment, Water, Heritage and the Arts of the Australian Government, "CO2 from human activities has caused the pH of ocean surface waters to drop by 0.11 pH units. This might not sound like much, but it is equivalent to a 30% increase in acidity. Unless CO2 emissions are curbed, the pH is expected to fall by 0.5 pH units by 2100, a 320% increase in acidity." (I'm ignoring, for the time being, the projections to 2100, as the focus of my initial suggestion concerns things that need updating/fixing regarding pH changes which have already taken place) source http://www.aad.gov.au/default.asp?casid=33583

c. While in "Blog" format the following url is officially published as "An information outlet on ocean acidification provided by EPOCA, the European Project on Ocean Acidification" where it is stated that "Approximately half of the carbon dioxide emitted into the atmosphere from human activities over the past 200 years has been absorbed by the oceans and as a result has lowered average ocean pH by 0.11 units." at http://oceanacidification.wordpress.com/2009/02/04/epa-weighs-action-on-ocean-acidification/ Thus another row should be added (I'm all for keeping the row about the -0.230 pH change which had occurred by the 1990s, for broader temporal context including changes which have occurred even in just the last decade or two) corresponding to this -0.11 in pH

2. This however brings up a problem with having a pH column. Not every study will estimate pre-industrial pH levels to have been precisely, exactly 8.179. How then could one add a row for "as of 2005-2010" for the -0.11 in pH? I suggest we omit the "pH" column (different science studies will have slightly different estimates) and continue to list the "pH change" column.

3. On the other hand, a new column should be added: percent change in acid concentration. This would be very useful to readers who are not used to working regularly with the logarithmic pH scale. We would of course keep the column with "pH change" as is given in the science literature, but add a column with percent change. In wikipedia articles one commonly adds "in feet" to a number given in meters, or C to F for temperature, and that is of course not "research" and we can similarly just add percent changes in concentration using a simple formula. As the wikipedia entry for pH indicates, while there are more complicated definitions for pH, the one which is adequate for our purposes here is p= -log(C) where p is the pH and C is the molar concentration of dissolved hydrogen ions ("acid concentration" in what follows, for brevity) and log means, 'base 10 log'. Just so the calculation is out in the open for any future editors:

Suppose C was the concentration at the outset of the industrial revolution, and p was the pH back then; then p= -log(C) Suppose also that the newer acidity concentration and pH are D and q respectively, so that q= -log(D).

Then the (positive) number p-q equals (-log(C))- (-log(D)) = log(D) - log(C)

Thus 10^(p-q) = 10^(log(D) - log(C)) = D/C. If this number D/C is 1.3 for example then that corresponds to a 30% increase in acid concentration.

For example the "percent increase in acidity" column added for the row representing the -0.075 would give D/C = 1.1885... or 19% increase to the nearest whole (or 18.9% to the nearest 0.1%). The row with -0.23 would have its "percent increase in acidity" column read 70% (to the nearest whole) or 69.8% to the nearest 0.1% since D/C = 1.698... in this case. For -0.355 D/C = 2.26.... or a 126% increase, or more than double-plus-a-quarter relative the original.

In the preceding p= 8.179 was used, but the above would work for converting any net change in pH into a percent change in acid concentration. For example the 0.11 change in pH cited in the multiple sources above, would give a D/C of 10^(0.11) or 1.288... or 28.8% (about 29%) increase (of course it may be that the actual estimate would yield a percent increase of 30% or a bit higher, if the -0.11 is rounded from a slightly larger net pH change given to 3 or more decimal places)

In sum, to update, and make more readable, I suggest: i. A row be added corresponding to the more recent -0.11 pH change, ii. The "pH" column be removed and the "pH change" column be kept and iii. A "percent change in acid concentration" column be added to be in line with most scientific summaries given to the public and policy makers which include % changes as well as pH changes. Cheers --Harel (talk) 03:09, 6 March 2010 (UTC)

Yes, this sounds like a good idea. The pH change (~0.1) associated with acidification does sound rather weedy compared to actual pH (~8), but the logarithmic scale hides the change in concentration of the pertinent chemical species. --PLUMBAGO 09:03, 17 March 2010 (UTC)

Finally implemented the main changes :) Harel (talk) 01:49, 8 August 2010 (UTC)

More updates (Aug 7 2010 discussion) to Acidification section: dates and upper ranges

Where it says "...and it is estimated that it will drop by a further 0.3 to 0.5 pH units (an additional doubling to tripling of today's post-industrial acid concentrations) by 2100 as the oceans absorb more anthropogenic CO2"

the third of the three links points to http://royalsociety.org/displaypagedoc.asp?id=13314 which is a dead link, so I've added annotation to that effect.

One of the other two links point at:

[2] http://web.archive.org/web/20080625100559/http://www.ipsl.jussieu.fr/~jomce/acidification/paper/Orr_OnlineNature04095.pdf

which states, "By the end of the century, it will become another 0.3-0.4 lower"under the IS92a scenario (which apparently represents, "(788 p.p.m.v. in the year 2100)"

and [1] the http://pangea.stanford.edu/research/Oceans/GES205/Caldeira_Science_Anthropogenic%20Carbon%20and%20ocean%20pH.pdf

which states "our general circulation model results indicate that continued release of fossil-fuel CO2 into the atmosphere could lead to a pH reduction of 0.7 units" (eye-balling - with the aid of a vertically aligned ruler actually - their figure 1a for the earliest time at which 0.7 is reaches, that would be about ~2180AD, a 0.6 lower pH starting about 5.5millimeters to the right of 2100 on my printout which would be (5.5/9)*250 circa 2150AD, 0.5 in pH reduction circa 2097AD. I suppose this paper is, in any case, the source of the "0.5" in the "0.3-0.5" in the above cited section?

If I'm reading the article correct however, these numbers (in figure 1a) are including the ~0.1 that's already happened? In which case the change by 2100 would be about "an additional 0.4", and the 0.6 and 0.7 would become "An additional 0.5 to 0.6" by the end of next (22nd) century...?

I'm not sure what to make of the unmarked red colored oval region apparently representing upper-ocean changes of more than -0.7 during roughly 2250-2750AD?

http://eprints.ifm-geomar.de/7878/1/965_Raven_2005_OceanAcidificationDueToIncreasing_Monogr_pubid13120.pdf

"If global emissions of CO2 from human activities continue to rise on current trends then the average pH of the oceans could fall by 0.5 units (equivalent to a three fold increase in the concentration of hydrogen ions) by the year 2100."

- - - - - - -

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VRT-4T4PT87-C&_user=961268&_coverDate=08%2F05%2F2008&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1424167733&_rerunOrigin=scholar.google&_acct=C000049399&_version=1&_urlVersion=0&_userid=961268&md5=32c7da14b88e19be783cdb4eba20fa87#bib5

cites decrease in pH by 0.4 "by 2100" as upper end of projections.

- - - - - - - - -

http://www.pnas.org/content/105/48/18860.full

says an additional -0.3 by 2080 or so. I haven't read the articles fully, just a quick read-over to get the basic numbers so if anyone sees details that are critical that I've missed please speak up.

- - - - - - - -

https://darchive.mblwhoilibrary.org/handle/1912/2834 Imminent ocean acidification in the Arctic projected with the NCAR global coupled carbon cycle-climate model finds upper end change to be -0.45 in pH, in the Arctic waters (by when? by 2100?) link to final revised paper is given from http://www.biogeosciences.net/6/515/2009/bg-6-515-2009.html to http://www.biogeosciences.net/6/515/2009/bg-6-515-2009.pdf if someone has time to review and summarize. I just peeked very briefly at it, it does seem the key numbers I quoted are correct.

- - - - - - -

I'd appreciate help from co-editors to consensus on above. Should it be 0.3 to 0.4 or to 0.45 by 2100, rather than 0.3 to 0.5? On the one hand we shouldn't put numbers higher than warranted; on the other hand, we don't want to under-state either (as the article had been doing with the "25% increase" rather than the more up to date 29% increase in H+ concentrations as of now, relative pre-industrial, so it would be good to make sure we have the latest strongest science Also, I think the chart include also expected effects by dates later than 2100, e.g. by 2250 or other dates cited in the research. If current projections are for 0.5 reductio in pH, or even more, by date X where X is later than 2100, that's still important to include. Finally, should give cumulative percent changes since pre-industrial. For example, 0.3 to 0.5 would be doubling to tripling over today's, but would be 2.5 to almost quadrupling of the pre-industrial H+ concentrations; the magnitude of projected future concentrations, relative re-industrial levels, are important for readers to have as well.Harel (talk) 01:58, 8 August 2010 (UTC)

Warming

Would warming of the oceans tend to accelerate or to reverse the acidification (or "dealkylisation" for the naive pedantics) of the oceans? (Also, would decreasing ocean salinity interact in any way?)

Clearly, rapid climatic changes and ocean pH fluctuations are bad for ecosystems and hence for people, but I'm still confused about the details: on one hand, we hear that carbon fossil fuels will increase the carbonic acid content of oceans, and on the other we hear that warming may run away with the oceans emitting CO2. Cesiumfrog (talk) 04:13, 17 April 2010 (UTC)

Hi Cesiumfrog. These are fair questions — I certainly don't know the answers, but I can give a few pointers to help.

At present, warmer surface temperatures in the tropics are associated with (the correlation is not particularly high) both slightly lower DIC concentrations and slightly higher saturation states for calcite and aragonite. So there's a sense in which warming may somewhat decrease some of the effects of acidification. However, since a warmer surface ocean will store less CO2 (since CO2 is less soluble with increasing temperature), the ocean will become less of a sink for anthropogenic emissions, with the result that more will remain in the atmosphere to change our climate. Also, as surface ocean waters with more DIC in them warm, then CO2 will become less soluble and will begin to outgas from the ocean to reach a new (lower) equilibrium concentration, tying in with your last point.

The story with salinity is less clear. It doesn't have as strong a relationship with CO2 solubility, although it does have a relationship with another relevant ocean property: alkalinity. In surface waters, alkalinity and salinity are quite strongly correlated because of freshwater fluxes (have a look at the plots here), to the extent that modellers have sometimes used surface salinity as a proxy for surface alkalinity (i.e. multiply salinity by a constant factor to estimate alkalinity). However, increasing alkalinity is a "good thing", since it both shifts the saturation states of calcite and aragonite upwards and allows the ocean to store more CO2 (have a look here at a commercial project looking into this). So decreases in salinity caused by glacial ice melt (which I presume is what you're getting at) may have an unhelpful effect on this point (although one also needs to think about the thermal and water volume effects of this mode of freshwater addition; which I haven't).

Regarding your point about the oceans emitting CO2, this will depend on factors such as: how high the atmospheric CO2 concentrations will get (which controls the atmosphere-ocean gradient in CO2 concentration); how warm (and where) the ocean will get; whether there are changes to deep ocean ventilation (i.e. how much does warming increase stratification and decrease ventilation?); and even whether there are changes to the natural carbon cycle of the ocean (e.g. will there be more or less plankton growth transporting organic carbon into the deep ocean?). These, and other, factors are interrelated and have (often large) uncertainties associated with them. Hence active research on these topics and a lot of computer modelling.

Anyway, I hope the above points help a little. If you can, have a look at some of the calculators at the bottom of the page. They can give you a quick idea as to how particular changes (temperature, salinity, alkalinity) affect properties like pH and CO2 solubility. Cheers, --PLUMBAGO 12:52, 17 May 2010 (UTC)

Add IAP STATEMENT ON OCEAN ACIDIFICATION from InterAcademy Panel on International Issues 2009 ?

Add IAP STATEMENT ON OCEAN ACIDIFICATION from InterAcademy Panel on International Issues 2009 ? 99.184.229.98 (talk) 21:50, 9 August 2010 (UTC)

pre-industrial pH in question

". Across the planet, the average pH of the ocean’s surface layer has declined 0.12 unit, to approximately 8.1, since the beginning of the industrial revolution." per which puts pre-industrial at (circa) 8.22 currently pre-industrial is listed as "8.179" What the pre-industrial level was, will of course affect all the "pH change since then" and "percent increase in acidity since then" figures. Since different papers may have somewhat different estimates of the pre-industrial level, I'll repeat an earlier suggestion to have the Chart just cite papers, "estimated pre-industrial level" and pH decline and % increase since pre-industrial hae those be the columns of the Chart in Acidification section maybe? Harel (talk) 03:40, 23 August 2010 (UTC)

Plumbago, since you were the one that replaced Mark Jacobson's figure of 8.25 with "aproximately 8.179" at http://en.wikipedia.org/w/index.php?title=Ocean_acidification&oldid=136368694 citing the GLODAP Atlas, where exactly did you find this number? I've searched high and low for any source for it. Given the considerable dependence of pH on latitude, what does it even mean? It seems to me that the Wikipedia article would be improved by working with anomalies as done for temperature instead of attaching significance to absolute pH values. But even if not, 8.2 would seem a more representative figure for the precision than 8.179. --Vaughan Pratt (talk) 23:53, 8 January 2011 (UTC)

Hi Vaughan. To be honest, I can't remember right now, but I can check up. I suspect that it's probably from something like Orr et al. (2005), but it may be another source. I don't think I've made it up, as it's a little too precise for my liking. I'll see what I can do. Cheers, --PLUMBAGO 11:25, 9 January 2011 (UTC)

OK, this number doesn't appear in Orr et al. (2005), or in its supplementary material. I've poked around a few other sources, but can't find either these numbers or comparable numbers with the same precision. I can only assume that I had a "moment of madness" back in 2007 (or some cut-and-paste disaster). Anyhow, in the absence of a source for these numbers, I'd suggest either changing back to Jacobson (2005), or to those quoted in the 2005 Royal Society report (8.18 pre-industrial; 8.07 "present-day"). I'll do this later today if I've time. Anyway, thanks for picking this up. And apologies for my inexplicable editing - I don't know what I was thinking back then. Cheers, --PLUMBAGO 12:35, 10 January 2011 (UTC)

← Further to the above, and after a deep dig through an old e-mail archive, I have now found where these numbers come from. They are from the simulations presented in the Orr et al. (2005) paper, but the table that they appear in didn't make the final, published version. As such, and since I can't find them elsewhere, they're "unreliable". To this end, I've reversed my original addition of them to the lead, but I've now noticed that they're used prominently in a table. I'll try to find out if they, or something like them, have appeared elsewhere. Sorry, in the meantime, for leaving the article a little in limbo. --PLUMBAGO 13:14, 24 March 2011 (UTC)

Sci Am August 2010 p.73

What can be done?

1) The U. S. Administration must enact the first ever National Ocean Policy (United States Commission on Ocean Policy), 2) The U. S. EPA must include CO2 as a pollutant, 3) Establish Marine Protected areas to allow species to recover from Exploitation, 4) Adjust catch limits to meet scientific recommendations rather than political desires, 5) The U. S. Administration will become a Leader in Marine Stewardship with the signing of the United Nations Convention on the Law of the Sea, and 6) More Science is needed and the Funding wherein it occurs.

~ Betaclamp (talk) 06:24, 26 October 2010 (UTC)

Fine, but these are just one set of recommendations - I can imagine (many) others. And they don't reference ocean acidification directly - only number 2 comes close to doing that, and even then this recommendation has as much to do with climate change as OA. Recommendations 3 and 4 appear to have nothing to do with OA whatsoever, and relate more to amending exploitation policy. Recommendation 6 could be applied to so many areas of science that it practically goes without saying. Finally, are these from a Scientific American editorial, or are they reported there from a wider statement made by some national science body? Just because something appears in a science journal doesn't make it notable. Anyway, my view is that these shouldn't really be added (again) to the article as they're far too generic. Cheers, --PLUMBAGO 08:02, 27 October 2010 (UTC)

Commentary from Drrock

Drrock writes in the main article ...

This article is misleading because it talks about SURFACE "acidification" of the oceans with the implicit idea that the WHOLE ocean is acidifying. The Ocean has a range of pH from 7.2-8.2 depending on many factors...and Antropogenic CO2 is essentially insignificant. The ocean is not 'acidic' until the pH of the WHOLE ocean drops below 7, and for the acidic effects to actually dissolve limestone, it would have to reach a pH of less than 5....the buffering effects of limestone in the ocean would prevent this from ever happening. Also, the map shows changes since 1700AD. Where did this come from? The concept of pH was essentially unknown at that time.

By way of answering these points ...

• The ocean is acidifying from the surface because this is in contact with the atmosphere (from where it gets anthropogenic CO2); the deep ocean is slowly acidifying as its waters are ventilated by surface water masses
• Yes, the ocean has a large dynamic range of pH, but that doesn't prevent ocean pH from undergoing systematic change (e.g. a comparable drop in pH everywhere); an analogy can be made with surface temperature on Earth - it ranges massively, so why are we worrying about a 2°C change?
• It is well-known that the ocean is on the alkaline side of things, and the article even remarks: "Note that, although the ocean is acidifying, its pH is still greater than 7 (that of neutral water), so the ocean could also be described as becoming less basic"
• Regarding limestone, you may wish to consider the article on the lysocline and how it relates to calcium carbonate dissolution in the ocean
• The "changes since 1700 CE" diagram relates to an analysis by the Global Ocean Data Analysis Project in which ocean DIC content was estimated for the "pre-industrial" using a deconvolution technique; there are references provided if you'd like to find out more about this
• Whether a concept is known about at a particular time does not prevent scientists from a later time making estimates of it; much of geology, palaeontology, astrophysics, etc., essentially involve estimating aspects of the distant past from present day observations

I hope these clarifications help. If you think the article does not adequately expand upon them, either discuss it here, or have a go editing. Cheers, --PLUMBAGO 08:44, 24 March 2011 (UTC)

Planetary boundaries

Add The average degree of seawater saturation in aragonite as a measure of ocean acidification is one of the Planetary boundaries. 99.19.46.34 (talk) 03:42, 30 March 2011 (UTC)

Why? — Arthur Rubin (talk) 04:24, 30 March 2011 (UTC)

Could you add detail to your questioning User:Arthur Rubin? 99.19.41.143 (talk) 04:59, 30 March 2011 (UTC)

Why? You've provided no reason to add it, or even for the relationship between acidification and "seawater saturation". — Arthur Rubin (talk) 08:35, 30 March 2011 (UTC)

"Boundaries for a Healthy Planet" by Jonathan Foley, Gretchen C. Daily, Robert Howarth, David A. Vaccari, Adele C. Morris, Eric F. Lambin, Scott C. Doney, Peter H. Gleick and David W. Fahey Scientific American April 2010 —Preceding unsigned comment added by 99.109.126.34 (talk) 17:16, 30 March 2011 (UTC)

You're advertising the topic, just as you were advertising 350.org when I first noticed you. However, even assuming it were an appropriate topic to link, a separate source relating "seawater saturation in aragonite" to this topic would be required for the link to planetary boundary to be appropriate. — Arthur Rubin (talk) 19:09, 30 March 2011 (UTC)

Scientific American articles are based on other citations internal in Scientific American articles already, see above article. Moot. Continue on Talk:Planetary boundaries? 99.119.128.35 (talk) 21:52, 30 March 2011 (UTC)

Wrong. And we have not resolved the question of whether any tangential links to planetary boundaries are appropriate. — Arthur Rubin (talk) 10:17, 31 March 2011 (UTC)

Arthur, please help me understand what you are attempting to say, what tangential links? Did you say you wanted supporting links (a separate source relating) ? 108.73.113.97 (talk) 00:26, 1 April 2011 (UTC)

The wikilink we're discussing is clearly tangential. For inclusion, at the very least, an independent source connecting the subject of this article (Ocean acidification) and the statement you want to add is required. — Arthur Rubin (talk) 05:33, 1 April 2011 (UTC)

Adding The average degree of seawater saturation in aragonite as a measure of ocean acidification is one of the Planetary boundaries. is what we are discussing. 99.181.154.122 (talk) 23:43, 2 April 2011 (UTC)

Exactly. Both aragonite and planetary boundaries are at most tangential, if not completely unrelated. — Arthur Rubin (talk) 01:08, 3 April 2011 (UTC)

Aragonite is a carbonate mineral, one of the two common, naturally occurring, crystal forms of calcium carbonate, CaCO3 (the other form is the mineral calcite.) ... see relation within Ocean acidification and Argonite article. 209.255.78.138 (talk) 18:22, 5 April 2011 (UTC)

"Planetary boundaries: Consider all consequences; Ocean acidification has impacts other than simple changes in pH, and these may need boundaries too." by Peter Brewer Published online: 23 September 2009 in Nature (journal). 209.255.78.138 (talk) 18:29, 5 April 2011 (UTC)

Better, but not really a source for a link to planetary boundaries; certainly not for a link to our present article on planetary boundaries. — Arthur Rubin (talk) 06:27, 6 April 2011 (UTC)

Coming into the middle of this discussion, I find it a little confusing. I'm surmising that this is a discussion that started elsewhere, and migrated to this article. If someone can please clarify the issue here and what is in dispute, that would be most helpful to those of us who have worked on this article previously. Thanks in advance. Arjuna (talk) 00:51, 7 April 2011 (UTC)

As I see it, the anon wants to link every planetary boundary mentioned in the article planetary boundaries to the article planetary boundaries. I (and some others, although not in this thread) don't think the target article is notable enough to link to. Because the anon wants it so, the discussion wanders through all the articles. I think the general discussion should remain in Talk:Planetary boundaries#Include link from each boundaries' corresponding wp article? and following sections. — Arthur Rubin (talk) 07:15, 7 April 2011 (UTC)

Another extreme comment, Mr. Rubin; from what I see, only wikilinked items in the column planetary boundary in the table from Planetary boundaries are attempted. There are more than three IP Users involved from what I have seen. 209.255.78.138 (talk) 18:18, 7 April 2011 (UTC)

Not being able to know your experience, Mr. Rubin, Wikipedia:Not every IP is a vandal might be useful to remember. 209.255.78.138 (talk) 19:34, 7 April 2011 (UTC)

I can't be sure that you're fragmenting the discussion intentionally, I apologize for that. However, you are fragmenting the central discussion as to whether any of the "boundaries" should link to the article planetary boundaries, and moving discussion of how one boundary should appear (if it should at all) to another boundary's talk page. — Arthur Rubin (talk) 22:18, 7 April 2011 (UTC)

I've got other fish to fry at the moment rather than to get involved in this discussion, but I do have one (friendly) suggestion for 209.255.78.138. I have not looked into this other than what is written here by you and AR, and so I have no reason to doubt your sincerity or the value of your contributions. However, I do think it is true that your efforts will be taken more seriously by other editors if you were to get a proper username. You can still remain anonymous, and it also allows other editors to contact you more easily. Arjuna (talk) 10:44, 8 April 2011 (UTC)

Wikipedia:User access levels, and also see threats from User:Arthur Rubin to other IP Users ... http://en.wikipedia.org/w/index.php?title=Talk:Tipping_point_(climatology)&diff=421723960&oldid=421705736 besides the seemingly unending insults ... http://en.wikipedia.org/w/index.php?title=Special:Contributions&limit=500&target=Arthur%20Rubin 99.109.126.27 (talk) 02:10, 15 April 2011 (UTC)

Arthur, please read the articles ("Global warming" portal as not supported) is inaccurate, and comments were given. ReAdd.

Arthur, please read the articles ("Global warming" portal as not supported, per History) is inaccurate, and comments were given. ReAdd Portal:Global warming. This article is an Effects of global warming. For this current article ...

There is also a suggestion that a decline in the coccolithophores may have secondary effects on climate, contributing to global warming by decreasing the Earth's albedo via their effects on oceanic cloud cover.[48]

A review by climate scientists at the RealClimate blog, of a 2005 report by the Royal Society of the UK similarly highlighted the centrality of the rates of change in the present anthropogenic acidification process, writing:[24] "The natural pH of the ocean is determined by a need to balance the deposition and burial of CaCO3 on the sea floor against the influx of Ca2+ and CO2− 3 into the ocean from dissolving rocks on land, called weathering. These processes stabilize the pH of the ocean, by a mechanism called CaCO3 compensation...The point of bringing it up again is to note that if the CO2 concentration of the atmosphere changes more slowly than this, as it always has throughout the Vostok record, the pH of the ocean will be relatively unaffected because CaCO3 compensation can keep up. The [present] fossil fuel acidification is much faster than natural changes, and so the acid spike will be more intense than the earth has seen in at least 800,000 years." A July 2010 article in Scientific American quoted marine geologist William Howard of the Antarctic Climate and Ecosystems Cooperative Research Center in Hobart, Tasmania stating that "the current rate of ocean acidification is about a hundred times faster than the most rapid events" in the geologic past.[25] Research at the University of South Florida has shown that in the 15-year period 1995-2010 alone, acidity has increased 6 percent in the upper 100 meters of the Pacific Ocean from Hawaii to Alaska.[26]

This will cause an elevation of ocean alkalinity, leading to the enhancement of the ocean as a reservoir for CO₂ with moderate (and potentially beneficial) implications for climate change as more CO2 leaves the atmosphere for the ocean.[53]

This looks like Wikipedia:Tendentious editing by you (still), User:Arthur Rubin. Please stop wasting wp's limited resources. 99.190.85.25 (talk) 22:53, 22 April 2011 (UTC)

I don't want to get involved in what looks like a running debate between 99.190.85.25 (btw, please get a proper username, it makes references in comments like this much easier) and AR, but I strongly agree that having including this article under the Global Warming category makes eminent sense. Frankly, I don't think this should be an especially contentious issue of debate. OA, while obviously a distinct phenomenon in many ways, is nonetheless related both scientifically as well as linked in many articles for the non-scientific audience. Let's settle this and move on. Arjuna (talk) 02:14, 23 April 2011 (UTC)

Thank you User:Arjuna909. 99.181.156.137 (talk) 04:38, 23 April 2011 (UTC)

There's a difference between Category:Global warming and Portal:Global warming. — Arthur Rubin (talk) 09:10, 19 May 2011 (UTC)

Were you intending to respond to Talk:Retreat of glaciers since 1850 with your Global warming Category comment? Or were you not responding to the Effects of global warming? 99.181.148.116 (talk) 10:09, 19 May 2011 (UTC)

No. You were asking for P:GW to be added, and giving arguments for C:GW — Arthur Rubin (talk) 17:39, 19 May 2011 (UTC)

World Ocean

The IP-hopping anon insists on have links such as [[World Ocean|Earth's oceans]] or Earth's [[World Ocean|ocean]]s instead of just Earth's oceans

Can anyone think of even a plausible reason for that link? — Arthur Rubin (talk) 09:13, 19 May 2011 (UTC)

From Oceans: "... these waters comprise one global, interconnected body of salt water sometimes referred to as the World Ocean or global ocean.". Is that plausible to you? 99.181.148.116 (talk) 09:48, 19 May 2011 (UTC)

Seems the world ocean page is rather lacking - the ocean article itself contain much more info and world ocean should likely be merged into it. Really sounds like someone's catchy phrase promoting ... some gaian stuff maybe? :) Per'aps I'll go back and undo the link I added the other day per someone's comment. Vsmith (talk) 10:07, 19 May 2011 (UTC)

This Gaia hypothesis stuff? 99.190.85.26 (talk) 17:18, 19 May 2011 (UTC)

"Inorganic carbon cycle" can only mean carbon not from living organisms ...

Organic compounds contain carbon bonds, hence the name Organic chemistry. "Inorganic carbon" is not the same as Inorganic chemistry, it cannot be since it has carbon, thus "Inorganic carbon" is from the very old understanding of "inorganic" meaning not from Life ... "organi-" as in Organism. If you read the Chemistry article you will find more to explain the history of the terms. 99.181.134.22 (talk) 06:17, 25 May 2011 (UTC)

Actually, organic compounds are often considered those which contain carbon-carbon bonds, so the inorganic carbon cycle would be those cycles which do not involve those organic compounds. I think it better to unlink entirely, than to have [[life|organic]] in the article. In any case CO
₂ is explicitly not an organic compound under any of the definitions, with CH
₄ being marginal. — Arthur Rubin (talk) 08:03, 25 May 2011 (UTC)

Notice inorganic carbon cycle. 97.87.29.188 (talk) 18:20, 25 May 2011 (UTC)

From Inorganic chemistry:

Inorganic chemistry is the branch of chemistry concerned with the properties and behavior of inorganic compounds. This field covers all chemical compounds except the myriad organic compounds (carbon based compounds, usually containing C-H bonds), which are the subjects of organic chemistry.

(bold is mine) 99.109.124.21 (talk) 03:34, 27 May 2011 (UTC)

From Organic chemistry:

Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation (by synthesis or by other means) of carbon-based compounds, hydrocarbons, and their derivatives.

Also see pre-1800's History_of_chemistry#The_vitalism_debate_and_organic_chemistry ... the sentence within this article in debate is using the old (ancient?) terms of Organic meaning Life-associated, and "non-living" (inanimate) of inorganic.

Update: User:Antony-22 has changed from

The carbon cycle comes in two forms: the organic carbon cycle and the (inanimate) inorganic carbon cycle. The inorganic carbon cycle is particularly relevant when discussing ocean acidification for it includes the many forms of dissolved CO
₂ present in the Earth's oceans.

to

The carbon cycle involves both organic compounds as well as inorganic carbon compounds such as carbon dioxide and the carbonates. The inorganic compounds are particularly relevant when discussing ocean acidification for it includes the many forms of dissolved CO
₂ present in the Earth's oceans.

Do the Organic chemistry and Inorganic chemistry articles need to be clarified also User:Antony-22? 99.109.124.21 (talk) 03:50, 27 May 2011 (UTC)

Ah, is the IP thinking of "Important classes of inorganic salts are the oxides, the carbonates, the sulfates and the halides." from Inorganic chemistry which opens by stating "The distinction between the two disciplines is far from absolute, and there is much overlap". So, this boils down to the question of whether chalk and CO₂ come under organic chemistry – seems not, perhaps the IP can find a source that says they do. . dave souza, talk 07:30, 27 May 2011 (UTC)

Add Biogeochemical cycle for simpler clarification? 99.56.123.78 (talk) 04:11, 28 May 2011 (UTC)