Saturday
Apr142012
by 
Bishop Hill
Bishop Hill The OK coral
Apr 14, 2012 Climate: WG2 Matt Ridley reports on a new paper in Current Biology, which finds that natural variations in pH along the Great Barrier Reef are larger than anything likely under global warming:
The good news from the research, says Professor Hughes, is that complete reef wipeouts appear unlikely due to temperature and pH alone.
"However, in many parts of the world, coral reefs are also threatened by much more local impacts, especially by pollution and over-fishing. We need to address all of the threats, including climate change, to give coral reefs a fighting chance for the future."
Reader Comments (162)
Apr 14, 2012 at 4:19 PM | Registered Commenter John Shade
With a comment like that I can't lurk any more. Brilliant. One of your best ever.
No matter how hard we try we don't seem able to get the message across that the oceans are not becoming "more acidic". They are marginally less alkaline on average than at other times in the relatively recent past but that average is meaningless — as averages usually are. A variation of 0.1 in the pH is barely measurable in exactly the same way as a variation of 0.1 in the global temperature is barely measurable (whatever the alarmists might say) and both are equally meaningless.
If the ocean pH ever reaches 7.0 (and I have yet to see any evidence that this is likely, or even possible) then you can start worrying about acidity.
Meanwhile the oceans are alkaline and the variation between one end of a coral reef and the other is greater than the infinitesimal variation in the overall variation which is as likely to be entirely natural as anything else.
If you have any proof that it isn't, anivegmin, then let's have it. Chapter and verse. Otherwise enough with the flannel already.
John Shade -- Nice piece. Sums up the desperation of the panic-stricken eco-fantasists nicely, I thought!
@anivegmin
Just summarise the evidence for the scaremongering so that we can all see it.
Just posting evidenceless speculations from paywalled papers does not cut the mustard.
Mike Jackson wrote:
"the variation between one end of a coral reef and the other is greater than the infinitesimal variation in the overall variation"
Wow three variations in one sentence, and an "infinitesimal variation in an overall variation" to boot! Nice one :-) Actually that is quite interesting - the variation across the reef thing. Can you provide a reference please. Actually a change in pH of 0.1 is, according to Wikipedia, a 30% change in H+ ion concentration (see my previous post). Is that really "infinitesimal"?
"Scientific papers are awash with if's, but's and maybe's. That's the way scientists talk. They are very much aware of the uncertainties in science and couch their language to reflect this."
I take it you are not a scientist, then? Perhaps you are related to Muir Russell - he used the 'that's the way scientists talk' excuse in his joke of a report. Having worked in technical R&D for 25 years I've read countless papers - those 'awash with if's, but's and maybe's' aren't worth the paper they are printed on, quite frankly.
anivegmin,
Looking at the paper to support your claim, Hönisch et. al, Science 335, 1058 (2012). and references and supplementary material
It is clear that the oceans have been more acidic in the past, and it is also clear that the paleo record they use does not have enough temporal resolution in the past to be conclusive about the current period.
William Morris,
My entire argument is that the deep ocean upwelling creates the extreme low end of ocean pH and most potential harmful effects. Your argument is incorrect: manmade CO2 does not uniformly lower the range the way you describe, the low end of the pH range is determined by upwelling of naturally CO2-rich water. Over the next hundreds of years that upwelling will contain increasing amounts of manmade CO2. That will be a uniform lowering as you describe but it will take centuries.
Here's a paper describing the dynamics: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0028983
For now those temporal patterns are very much natural.
Latimer Alder,
I have given you 2 direct links and a website that contains a majority of direct links.
TerryS, Patagon,
The authors of the paper acknowledge the uncertainties arising from the temporal resolution of their proxies, and they don't completely rule out the "potential for episodes of intense acidification". But consider that an approximate drop in pH of 0.1 in the past couple of hundred years, with a further 0.2-0.3 predicted for the next 50-100 years, would be a big almost vertical drop in the context of a time period covering millions of years. This would be an episode of "intense acidification" having consequences for the environment humans will have to live in. This paper also has to be seen in the wider context of other literature on both ocean chemistry and atmospheric chemistry. That's what experts are for.
Mike Jackson,
Seeing as you are an expert in both statistical analysis and chemistry I'll demure to your knowledge.
Anivegmin -
On what evidence? Can you produce any evidence that any 19th century scientist could measure PH to an accuracy of 0.1? Even 0.5 would be a remarkable claim.
More speculation. Your CO2 end-is-nigh bollocks may be suffice for you and your post-normal science, but it won't cut the mustard here. Stop digging, you are making a fool of yourself.
William Morris
Perhaps Mike Jackson should not have described a 0.1 change in ph as "infinitesimal". "Barely measureable" would have been more to the point. It seems the accuracy of laboratory measurements of ph are about +/- 0.05.
http://www.all-about-ph.com/ph-test.html
Apr 14, 2012 at 1:15 PM | anivegmin
You are still embarassing. Stop, Look, Listen and learn.
Embarassing and at times dishonest (my apologies if parliamentary rules are being applied mister speaker). Check out the "Singer on Mann" thread (and numerous others).
Did you know that measuring the pH of seawater is problematic and not as easy or accurate as some would let on? It has to do with all the dissolved salts which also vary over time and space.
Dreadnought: it depends what you mean by 'measurable'. If you take a series of thousands of samples over several years and plot them on a graph, they might well be inaccurate by +/- 0.05 individually. But if you fit a curve to the measurements and it slopes downward, you can with justification say the pH (or whatever is being measured) is decreasing. The size of decrease can be 'measured' by the slope of the line.
Similarly, with the famous hockey stick graph. If one accepts any part of the graph as being believable (for examples parts that point downward) one is judging it by the slope of a series of individually highly inaccurate readings.
@angevin
'This paper also has to be seen in the wider context of other literature on both ocean chemistry and atmospheric chemistry. That's what experts are for?'
If this sentence has any meaning other than an appeal to (your own?) authority, please let us know what you think it is. It is difficult to construe it as a rather crude attmept to change the subject from an area you have been found wanting..
I'm especially interested in your understanding more or your discussion of atmospheric chemistry and how it affects pH - a subject I have some slight academic acquaintance with.
Dreadnought
You're right. I'll settle for "barely measurable".
As for our new trolls, one has immediately identified himself as such by addressing the style of my post rather than the content and has failed to address the main point.
The other has made himself look ridiculous by trying to be offensive and using words he obviously doesn't understand.
How demure of him!
If either would behave more like adults than adolescents they might be worth a few minutes of my time. Unfortunately ...
'It is difficult to construe it as a rather crude attmept to change the subject from an area you have been found wanting..
Oops
Mispront. 'It is difficult to construe as *other* than a rather crude......'
@mike jackson
'If either would behave more like adults than adolescents they might be worth a few minutes of my time. Unfortunately ...'
And they might have begun to understand acid/alkali chemistry and pH. For a concept that used to be introduced in Chemistry O level, it is quite remarkable how few alarmist commentators show even a passing acquaintance with it.
Maybe in the state of Calfornia it works differently?? Like the guys who passed the law that the value of pi was exactly 3.0000000. And wondered why the natural world didn't do what they'd told it to.
Apr 14, 2012 at 5:26 PM William Morris said:
'Actually a change in pH of 0.1 is, according to Wikipedia, a 30% change in H+ ion concentration (see my previous post). Is that really "infinitesimal"?'
As I understand it, the pH scale is logarithmic. To change from pH x to PH x-1 entails a tenfold increase in the concentration of hydrogen ions. So to go from pH 8 (which is alkaline) to pH 7 (which latter is deemed neutral) means a tenfold increase in the hydrogen ion concentration. The same could be said for a decrease from pH 9 to pH 8, or pH 7 to pH 6, for example; there too, in each case the increase in the number of hydrogen ions would be tenfold.
A twofold increase in hydrogen ions (i.e. doubling) would be a 100% increase. But we are talking about a tenfold increase for a single pH point decrease, which is an increase of 1,000,000,000%.
So is a change of 30% in pH infinitesimal? I'd say so. One needs to put the percentages in context. Living aquatic organisms can generally tolerate pH changes much larger than 0.1. Rainwater varies in pH from 6.5-8, and you can drink water at even higher or lower pH's.
My calculations are based on memories from A-level chemistry, which I passed in 1968. If I've made a mistake, I'd welcome correction.
William Morris
If you take a series of thousands of samples over several years and plot them on a graph, they might well be inaccurate by +/- 0.05 individually. But if you fit a curve to the measurements and it slopes downward, you can with justification say the pH (or whatever is being measured) is decreasing. The size of decrease can be 'measured' by the slope of the line.
Does that not depend on the width of the error bars? You might be unable to conclude reliably whether the slope should be downward, eg if you can plot a horizontal or upward-sloping line within the confines of the error range.
One thing that has always puzzled me is the apparent nature of Man Made CO2 to be both in the atmosphere and dissolved in the oceans at the same time. Do they deduct the CO2 dissolved in the oceans from the atmospheric content causing unprecedented warming in the models?
Michael Larkin -
An arithmetic error in your last (7:31 PM). A full point drop in pH corresponds to a 10-fold increase in the concentration of hydrogen ions, or a 900% increase. A doubling of the hydrogen ion concentration, +100%, means a drop of about 0.3 in pH.
To the main point, there is a good reason why pH is a logarithmic scale, namely the large range of naturally-occurring ion concentration. Your cited range of 1.5 in the pH in rainwater, corresponds to a factor of around 30 in ionic concentration. The natural world seems to have no problem with that. [Well, technically, the plants/animals which raised an objection have all ceased to be. So of course we're left with tolerant species.] Quoting a pH change as a percentage change in ionic concentration, while technically accurate, seems to be an exercise in emotive language rather than a scientific matter.
Edit: apparently it's drinking water (not rainwater) which has a pH range of 6.5-8.0. Rainwater is typically between 5.5 and 6.0.
" I haven't got the time to trawl through all the papers on the subject to ascertain their statistical significance or otherwise"
You either come up with the study that calculated the pH for millions and millions of years, and *show*, statistically, how present ranges and rates are significantly different.
Or you drop the use of such words as 'significant', and 'unprecedented'.
If you inferred that something unprecedented is taking place, and it is not based on statistical inference, you don't know what you are talking about.
Harold W - I'm grateful for your correction. We're talking a 900% increase - I see I went overboard, applying a 10-fold multiplier for each doubling, rather than a 2-fold one. My bad. But still, in that context, a 30% increase in H+ ion concentration is small beer.
My back of the envelope, beer assisted, calculation gives a change of 25% in [H]+ for the change from 8.2 to 8.1. ([H]+ at 8.2 is 6.4nmol/l and at 8.1 is 8nmol/l. That's nanomol!) As Harold points out, the reason for using a log scale is precisely that the changes in [H]+ are large. The number is however small. As Mike and others point out above, measuring pH is rather tricky, even in known solutions. The complexity of sea-water makes it doubly so. Despite this, it is possible to achieve reasonable trend measurement, but this paper seems to be showing what others have in the past - natural systems are far more variable than one would think. Anivegmin is trying to divert attention from this using a simplistic understanding of the underlying chemistry.
Have no fear guys! If the ocean acidification scare fails to be a hit with the audience, they have an understudy for her waiting in the wings. Wait for it, The Ocean Oxgen Crisis!
http://thinkprogress.org/climate/2010/08/15/206550/a-looming-oxygen-crisis-and-its-impact-on-our-oceans/
Oh, the joys of 'policy relevant' research funding. Sad, really - so much waste - genuflexion to the clamour of the times.
In my biochemistry days (about 20 years ago) I occasionally had to measure pH, or more usually to prepare solutions at desired pH values, and would normally work at a precision of 0.1. But I was very aware that what I was actually measuring was pH* (that is, the pH reading as reported by a pH meter) and not in any real sense pH. To get actual pH values you would have to (1) calibrate the meter against known standards, (2) correct for temperature, (3) correct for dissolved salts, and (4) in my case correct for deuteration levels. I also knew that making a water solution at a fixed pH was difficult unless the pH was below 5 or above 9; within the middle range the hydronium/hydroxide ion concentrations were so low that they would change if you so much as looked at the sample. If you wanted a fixed pH value around 7 you really had to buffer the solution or else your measurement was virtually meaningless.
I believe that corals can survive at a ph of 6 - a long way to go before the oceans are at that level!
Mike Jackson said:
"As for our new trolls, one has immediately identified himself as such by addressing the style of my post rather than the content and has failed to address the main point."
I guess you mean me. What a thin skin you have - didn't you notice the smiley - it was a joke. Should be acceptable on an entertainment site like this.
Your "main point" was facile, so I didn't address it. You suggest that because a solution is alkaline you cannot acidify it. So if I have a pH 8 solution and I pour in some acid, you would claim that I am not acidifying it. We could say neutralising it if you preferred, but such word play is just designed to confuse the poor souls on the site who don't have a clue anyway.
"pH 8.2 is alkaline, pH 8.1 is still alkaline. You haven't made it acid!!! Rah Rah!"
Like I said this site is entertainment, not science. You need 'trolls' so that you can throw them to the lions and have fans shout "go on Mike, get on 'im!". Without 'trolls' these discussions would become just a BH echo box. There is no serious science here; no physics or chemistry primers to educate the uninitiated; no references to standard texts where you can check the numerous 'facts' that are trotted out. No links to experiments that can be tried to prove your ideas; no papers published by authoritative posters as they somehow can't get round to writing up their theories; It is entertainment - and it is entertaining. Then again perhaps you also need trolls to have a common target - without them, those with conflicting ideas expressed here might start fighting amongst themselves - those that accept 1 degree of warming against those that don't know when they have a foot in a hot bucket etc (see BYJ types 1, 2 and 3).
diogenes: refer to http://en.wikipedia.org/wiki/Curve_fitting - it might resolve your confusion.
"We could say neutralising it if you preferred, but such word play is just designed to confuse the poor souls on the site who don't have a clue anyway. "
Poor souls such as (Prof) Johnathon Jones who posted a few comments above? Do I fit your description as not having a clue? Where's your chemistry degree from?
'Neutralising' is by far the more accurate term for the sentences discussed above. You could be asking the 'real' scientists why they allow press releases to be written sloppily.
Now, to stay on topic William, how about commenting on the fact that the natural pH variation, and that induced by poor ecosystem management, is larger than any projected climatic contribution.
@william morris
'We could say neutralising it if you preferred'
Excellent. I do so prefer. It accurately describes the chemistry. So I look forward to reading all about the oncoming dangers of 'ocean neutralisation'.
Good luck with getting grant money for that.
A method for estimating ocean pH over the last 60 million years is given in this paper (Pearson and Palmer, Nature, 2000 – pdf here). It apparently relies on the pH-dependence of the isotope fractionation of boron, found as a trace element in the carbonate shells of foraminifera in ocean sediments.
Figure 1 shows the change in pH with time – according to this proxy, the pH was 7.3 – 7.6 from 50 to 60 million years ago which was associated with atmospheric CO2 levels of about 3000 ppm (calculated from the pH estimate) – and higher temperatures (endearingly labelled in figure 4 as the ‘early Eocene climate optimum’). After that pH rose to current levels.
So, anivegmin, you say “The oceans are acidifying at a RATE unseen for 100's of million's of years.” – well, the ocean seems to have become about 0.7 pH units more alkaline in the last 60 million years. The resolution is of the order of a million years or so – we have no idea of the rate of the changes.
As an aside, I found this paper via a link from JNCC DEFRA (pdf here)
whose slide 3 only shows the Pearson and Palmer data from 25 million years ago and not the whole timescale (thus omitting the earlier, more acidic, pH values). Slide 3 says “By 2050 the pH range will be discrete from the pre-industrial pH range. We will be in unknown territory”… well, only because they decided not to include that ‘territory’ on the graph.
Cumbrian Lad: I didn't notice Prof Jones objecting to the term 'acidification', but maybe I missed it.
Re: "on the fact that the natural pH variation, and that induced by poor ecosystem management, is larger than any projected climatic contribution."
I already commented on that at Apr 14, 2012 at 3:45 PM
I must have missed your apology to Mike, and others, for your 9.02 comment?
in what way does curve fitting describe the fact that corals appear to demonstrate the ability to survive in water of varying acidity/alkalinity? ...I know...it explodes the point that the warmistas would like to declare. Bye bye William Morris...next point please?
William Morris said "I already commented on that at Apr 14, 2012 at 3:45 PM" where he said "If the normal variation of pH is between 8.1 and 8.2 .... and you reduce it by 0.1, it will be varying between 8.0 and 8.1."
That is incorrect. For small ranges (e.g. 0.01 units) in daily fluctuations it would be correct. For the 0.1 unit fluctuations that you are referring to (usually seasonal but can be more often), the source of the low pH water is mainly upwelling seawater that is naturally CO2 rich and is hundreds of years old. The presence of man-made CO2 upon arrival at the surface will generally not lower the pH further since the water is replaced much faster than CO2 is absorbed.
diogenes: "eg if you can plot a horizontal or upward-sloping line within the confines of the error range." I don't think you understand how curves are plotted given a collection of data points. Hence my reference to curve fitting. It is relevant; I suggest you read it.
Cumbrian Lad: apology for what? I was called a troll and I replied with some home truths. What was untrue or offensive?
Mike Jackson/Dreadnought: "I'll settle for "barely measurable". Here's an analogy. Personal income, just like H+ ion concentration (pH) could well be plotted on a log scale; it varies from a few hundred pounds a year to many millions a year. Are you telling me that, whatever your actual income on that scale, if offered a 30% increase you would say 'no its a barely measurable increase - give it to BH'?
William Morris and anivegmin, I suggest you read Willis Eschenbach's excellent post on the subject of ph and oceans, and the informative comments (including from chemists who have forgotten more about measuring ph than most of us will ever know) here:
http://wattsupwiththat.com/2011/12/27/the-ocean-is-not-getting-acidified/
An important take away from this post and the comments is that measuring ph in oceans is fraught with difficulty even in this day and age. Variations in one spot over a day can exceed even the wildest predictions of alarmists; variations between locations are even larger.
How anyone could talk about changes over tens of millions of years except if the changes were of a very large magnitude indeed is impossible to, ahem, fathom. And, localising such changes in any meaningful way over such a time period while also attributing them to CO2 is like discussing the evolution of unicorns.
I think you may have strayed into the wrong website. SkS is probably more your scene.
Are you telling me that, whatever your actual income on that scale, if offered a 30% increase you would say 'no its a barely measurable increase - give it to BH'?
To Bill Gates an increase of 30% in my salary is barely measurable.
In any case, as pointed out many times above, we use a log scale for pH because that is how it actually feels to animals.
Nature often works like that. For example, if you are given a room lit by a 100W bulb and it is increased to a 125W bulb the difference is barely noticeable, because we do not perceive light linearly, but exponentially. A 25% increase is perceived as much less. It's often 1,000 times brighter outside than inside, yet we are not blinded when we walk outside.
BTW, stop with the 30% for each 0.1 of pH. Its 26%, because 1.26^10 = 10
Ah, the distinctive aroma of Passing Clouds!
I suppose it must be quite flattering to have somebody trying to blow smoke up one’s nose?
eric (skeptic): the text you quoted is self-evidently true. In the specific case of upwellings it may well be that pH increases cannot be detected because of the upwelling CO2 (although even then graphical treatment should show a trend if one exists). But according to Wikipedia, upwelling occurs predominantly around the coasts (plus at the equator and in the Southern Ocean). That leave a lot of other ocean. Your PLoS ONE reference shows that open-ocean waters (those surveyed) have very little variation in pH over a 30 day period.
Bishop Hill is not intended to be an educational resource for school pupils and/or undergraduates. It assumes that readers have some knowledge of the basics at least. It is a place for analysis and critical thinking. And there is more incisive, rational scientific thinking and integrity in a typical Bishop Hill thread than in a bucket load of the statistically gerrymandered pseudo science produced by the team. e.g. Steig's method massacred. You are right about one thing - it can also be entertaining, especially when some naive and dim-witted trolls come along.
If increasing CO2 in the atmosphere has the ability to increase the temperature of this planet.
Why does it not do so?
Is it just holding back for the best price?
do you have any facts to lay on the table, William Morris? Any data to plot? Any error bars?
William Morris, there's not much in the middle of the ocean that is vulnerable to pH and the coasts where the upwelling takes place houses the fixed plants and animals like corals. Those have mostly been exposed to pH fluctuations lower than the next 100 years or so of manmade drop (assuming it stays constant). However I am glad you read the reference.
johanna: thanks for the link. Actually this is a digest of the link posted by sceptic eric (at PLoS ONE) and is much easier to digest. Shame I didn't find that before ploughing through the PLoS ONE paper :-) An interesting quote:
Sure, a hard-core scientist hearing “acidify” might think “decreasing pH”.
Note he doesn't say AGW scientist, so I guess it is a term in wide use outside the AGW circle. Arguably neutralisation is more accurate.
I agree that with such wild variations in pH around the oceans, claiming to measure a record back over millennia, let alone epochs sounds fanciful. But that won't stop people trying :-)
BTW what is SkS?
MooLoo: "we use a log scale for pH" as did I (sort of) in my example. For example an income of $100 yearly could be considered '2', $1000 as 3, $10000 as 4 etc. But it doesn't change the fact that a 30% increase is not 'barely measurable'. Neither is the difference between a 100 and a 125W bulb.
"BTW, stop with the 30% for each 0.1 of pH. Its 26%, because 1.26^10 = 10"
Yes I agree it is important to get that right. Actually I misquoted Wikipedia. The correct quote is a change in pH from 8.25 to 8.14 "representing an increase of almost 30% in "acidity" (H+ ion concentration) in the world's oceans.". In other words a change of pH of 1.1% Phew! I'm glad we got that corrected :-)
lapogus: "it can also be entertaining, especially when some naive and dim-witted trolls come along"
thanks, I'm doing my best :-)
I think that anivegmin and Mr. Morris are barking up the wrong acid tree. Carbonic acid is a week acid but sulphuric acid is a very strong acid. The many volcanoes under the sea belch prodigious quantities of sulfur into the see under just the right conditions to make sulfuric acid. So far they have not succeeded to make the ocean water anything but alkaline even after, well, a very long time.
But it doesn't change the fact that a 30% increase is not 'barely measurable'. Neither is the difference between a 100 and a 125W bulb.
The difference between 100 and 125 W is 25% when measured by a physical instrument. But not when it measured with our eyes. Since we judge the amount of light with our eyes the percentage change on a instrument is irrelevant, no matter how technically correct.
Same with pH. Animals don't notice a 0.1 increase as anything much at all. Who cares if the H+ concentration is 25% higher if it doesn't feel like that?
You seem to understand the concept of a log scale mathematically, but refuse to grasp that we use them because they reflect reality. A 0.2 change in pH is felt as a small change in acidity, even as the concentration of H+ ions is doubled.
Sorry, that should be "A 0.3 change in pH is felt as a small change in acidity, even as the concentration of H+ ions is doubled."