New paper debunks 'ocean acidification' scare, finds warming increases pH


Via the Hockey Schtick:

A paper published Friday in Climate of the Past reconstructs water pH and temperature from a lake in central Japan over the past 280,000 years and clearly shows that pH increases [becomes more basic or alkaline] due to warmer temperatures, and vice-versa, becomes more acidic [or “acidified” if you prefer] due to cooling temperatures. This finding is the opposite of the false assumptions behind the “ocean acidification” scare, but is compatible with the basic chemistry of Henry’s Law and outgassing of CO2 from the oceans with warming. 

Thus, if global warming resumes after the “pause,” ocean temperatures will rise along with CO2 outgassing, which will make the oceans more basic, not acidic. You simply cannot have it both ways:

“Either the oceans are getting warmer and the CO2 concentration in seawater is decreasing, which means that ocean acidification from man-made CO2 from the atmosphere is nonsense. 

Or the oceans are getting cooler and the man-made CO2 from the atmosphere is dissolving in those cooler oceans and causing – insignificant – ocean acidification, which means that warming oceans and the associated sea level rises are nonsense. 

Take your pick – REAL SCIENCE says you can’t have both.”

In addition, the paper shows that pH of the lake varied over a wide range from ~7.5 to 8.8 simply depending on the temperature of each month of the year. As the “acidification” alarmists like to say, a variation of 1.3 pH units is equivalent to a 1995% change in hydrogen ions due to the logarithmic pH scale, just over a single year! Summer months are of course associated with warmer temperatures and more alkaline, higher pH and winter months associated with colder temperatures and much more “acidified” lower pH values. Note also how pH varies widely over ~7.5 to 8.8 simply dependent on the depth at a given time, because colder deeper waters can hold higher partial pressures of CO2 than the warmer surface waters:

Second graph from left shows reconstructed pH over the past 280,000 years, third graph from left shows temperature reconstruction. Note how these move in sync, although the paper says pH lags temperature sometimes by up to several thousand years, i.e. just like CO2 lags temperature in the ice core records also by about 1000 years.

“Comparison with pollen assemblage in Lake Biwa cores suggests that lake water pH was determined by summer temperature in low-eccentricity periods, while it was determined by summer precipitation in high-eccentricity periods. From 130 to 55 ka, variation in lake pH (summer precipitation) lagged behind that in summer temperature by several thousand years.”

These findings completely contradict the basis of the CAGW “acidification” scare and instead show that warming should make the oceans more alkaline, not “acidic.”

Clim. Past, 10, 1843-1855, 2014


T. Ajioka1, M. Yamamoto1,2, K. Takemura3, A. Hayashida4, and H. Kitagawa5

1Graduate School of Environmental Science, Hokkaido University, Kita-10, Nishi-5, Kita-ku, Sapporo 060-0810, Japan

2Faculty of Environmental Earth Science, Hokkaido University, Kita-10, Nishi-5, Kita-ku, Sapporo 060-0810, Japan

3Institute for Geothermal Science, Kyoto University, Noguchihara, Beppu, Ohita 874-0903, Japan

4Department of Environmental Systems Science, Doshisha University, 1–3 Tatara-Miyakodani, Kyotanabe, Kyoto 612-0321, Japan

5Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601, Japan


We generated a 280 000 yr record of water pH and temperature in Lake Biwa, central Japan, by analysing the methylation index (MBT) and cyclisation ratio (CBT) of branched tetraethers in sediments from piston and borehole cores. Our aim was to understand the responses of precipitation and air temperature in central Japan to the East Asian monsoon variability on orbital timescales. Because the water pH in Lake Biwa is determined by phosphorus and alkali cation inputs, the record of water pH should indicate the changes in precipitation and temperature in central Japan. Comparison with a pollen assemblage in a Lake Biwa core suggests that lake water pH was determined by summer temperature in the low-eccentricity period before 55 ka, while it was determined by summer precipitation in the high-eccentricity period after 55 ka. From 130 to 55 ka, the variation in lake pH (summer precipitation) lagged behind that in summer temperature by several thousand years. This perspective is consistent with the conclusions of previous studies (Igarashi and Oba, 2006; Yamamoto, 2009), in that the temperature variation preceded the precipitation variation in central Japan.


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The Seattle Times will not be happy about this.


One lake.
Happens to be in Japan. But – one lake.
Moving on . . . . . . .

Gary Pearse

Auto, you clearly aren’t a scientist. 1) The lake is water and water everywhere is water. How many lakes do YOU need. Don’t be amazed if the same thing is found in other lakes where a record is available. As a skeptic, I would like to see the work replicated by other scientists. Maybe why it is significant would be clearer if I gave an analogy. If you need a certain thrust to make a trip to the moon in a space ship, take it on faith if you have to, that the same parameters will work again to get you to the moon. It wasn’t a happy accident. 2) Tell me in a paragraph just what convinced you of CAGW. Tell me what you think of them changing the name from global warming to climate change and what strikes you about an 18 yr pause in global warming.


And this lake is nothing like the ocean, which happens to be a carbonate system. This shows either the ignorance or clever obfuscation of the Climate Schtick. Take your pick — you can’t have it both ways.

k scott denison

Barry, Auto please share references to the chemistry of ocean water that would make it retain CO2 with increasing temperature.

Sorry for my late arrival here to defend my hockey schtick post, as I was traveling and am just now catching up with other blogs. Ferdinand Engelbeen made comments at my blog and I replied as follows. I am repeating these comments & replies here since they also address the same criticisms of several other commenters here:
Ferdinand Engelbeen October 21, 2014 at 6:31 AM
Sorry, but wrong title:
– The pH changes in a fresh water lake are completely unrelated to pH changes in seawater.
– Henry’s law still is in full force, but says that for a given temperature the amount dissolved is directly proportional to the partial pressure of the gas in the atmosphere.
The influence of temperature is ~0.0114 pH unit per °C. As 1°C is about the maximum warming since the LIA, that is all what can be expected of warming oceans. See:
The warming of the oceans changes the equilibrium with the atmosphere with ~8 ppmv/°C. The real increase since 1850 is ~110 ppmv.
That means that more CO2 is pressed into the oceans, not reverse. Which is measured in 4 long term series and lots of more sporadic/regular sea ships measurements over time.
Here Fig. 5 from Bermuda:
and Fig. 1 from Hawaii:
Thus sorry, the article doesn’t debunk anything…
Reply by MS October 21, 2014 at 9:50 PM
Hi Ferdinand,
“The pH changes in a fresh water lake are completely unrelated to pH changes in seawater.”
Not true, temperature dominates over pCO2 to control solubility in both seawater and fresh water.
“Henry’s law still is in full force, but says that for a given temperature the amount dissolved is directly proportional to the partial pressure of the gas in the atmosphere.”
Temperature dominates over pCO2 changes as the primary driver of Henry’s Law as clearly shown by fig 1 and 2 above. Fig 2 covers 2 glacial-interglacial cycles and shows T drives Henry’s law and CO2 outgassing on a long-term timescale. Fig 1 shows T drives Henry’s Law on a month and daily basis, showing solubility of CO2 changes not only with monthly surface temperature, but daily dependent upon temperature at various thermoclines.
“The influence of temperature is ~0.0114 pH unit per °C. As 1°C is about the maximum warming since the LIA, that is all what can be expected of warming oceans. ”
As shown by fig 1 above, a ~7C cooling is associated with a ~0.8 pH “acidification,” about an order of magnitude higher than you are claiming.
“Thus sorry, the article doesn’t debunk anything…”
Yes it does, for the reasons set forth above.
Ferdinand Engelbeen October 22, 2014 at 4:53 AM
There are lots of differences between what happens in a fresh water lake and what happens in the oceans:
The solubility of CO2 in fresh water decreases with ~5% for a temperature increase from 15 to 16°C:
The solubility of CO2 in seawater changes with less than 1% for the same temperature change. See Fig. 2 in:
That is because the solubility of CO2 remains the same for both cases per Henry’s law, but free CO2 is only 1% in seawater. The rest are (bi)carbonates which don’t play a direct role in CO2 partial pressure, but do react on free CO2 changes.
The solubility of CO2 in seawater is also much higher than in fresh water.
pH changes in fresh water can be huge and at CO2 saturation, the pH of the solution is between 4 and 5. Any change in CO2 due to temperature can have a huge effect. As the change in solubility is high in fresh water, the effect is high on pH too. For seawater, again the effect of temperature on CO2 levels is way smaller and the effect of changes in CO2 concentration on pH changes is also a lot smaller because of the buffer effect of the solution.
Thus again what happens in a fresh water lake with very little buffer capacity and much less CO2 in solution is not comparable to what happens in the oceans…
Further, have a look at the seasonal changes of pH in the ocean surface of Bermuda:
in figure 4 the seasonal temperature change is 8°C while the accompanying change in pH is ~0.1 unit. Compare that to the 0.8 pH unit change in the fresh water lake for near the same temperature change…
Thus definitively fresh water lakes and oceans are not comparable for their reactions on changes in CO2, pH, temperature, etc.
Reply by MS October 22, 2014 at 11:24 AM
I agree that “any change in CO2 due to temperature can have a huge effect” and that temperature dominates over atmospheric pCO2 to determine dissolved pCO2.
The ocean does of course have nearly unlimited buffering capacity and your 2nd link is just absolutely false to claim “Apparently, the ocean is not strongly buffered.” Thus, the effect of temperature is smaller than for a lake, but nonetheless still dominates over atmospheric pCO2 to control solubility and dissolved pCO2 levels. The huge ocean buffering capacity, more than enough to accommodate burning of all stores of fossil fuels, along with decreased solubility with warming, both debunk the “acidification” scare.

Steve in Seattle

The Seattle Times ignores ANY current climate science or solar physics papers that do NOT support the agenda. Left of liberals in King county never see such reporting.

The ocean acidification scare was always going to be a crock. The outgassing from any warming of the ocean utterly swamps any uptake due to higher CO2 concentrations in the air. Nice to see some measurements which confirm this basic science.


I put this to a warmist marine biologist in discussion some months ago together with a simplistic description of global atmospheric circulation (Hadley Cells, etc) … and exactly the outcomes concluded by this paper. Needless to say, it seemed beyond him to comprehend challenge to his wedlock with acidification claptrap. Recently similarly engaged him again, and he has not advanced his knowledge.


They do want it both ways. They tell me the oceans are warming and are turning more acidic. They tell me about thermal expansion, glacial spiral meltdown and all that. They have to look at all those assertions and make sense out of it.


And what about the partial pressure component of Henry’s Law?
“At a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.”
The increases in partial pressure is a lot more than the temperature rise. The overall affect will be decrease in pH in Oceans.


If the temperature keeps going sideways, yeah.

Gary Pearse

If the only thing happening is increase in partial pressure, yes. However, it seems you’ve missed the big bugaboo about rising temperatures causing ocean acidification. Believe you me, the CAGW folks wouldn’t be mollified by your observation – CO2 rise with no temperature rise.

“The increases in partial pressure is a lot more than the temperature rise. The overall affect will be decrease in pH in Oceans.”
This is false because as figure 1 above shows, pH and dissolved pCO2 stratify by layer, with pCO2 increasing and pH decreasing according to the temperature at various thermoclines. Temperature dominates over changes in pCO2 to control water pH levels by thermocline. Figure 1 shows a huge 1.3 pH variation over the top 20 meters clearly controlled by temperature, not well-mixed CO2 levels.
The fact that the ocean has essentially unlimited buffering capacity means that the change in pH due to temperature/solubility will be less than in a freshwater lake, but nonetheless, ocean pH measurements clearly show wide variation of .35 pH units over a few days from the same thermocline, as compared to this paper finding a variation of ~1.3pH units over monthly resolution in a lake reconstruction. But, the important point is the sign of change is the same and temperature still dominates over pCO2 levels to control pH.
The Monterey Bay Pacific Ocean data also shows no pH trend.
Here’s a paper debunking the comments here claiming that the same Henry’s Law relationship is not found in the oceans as in this lake, as this paper’s data is from the Pacific Ocean and finds the exact same relation:
“Ωarag [aragonite buffer] and pH decrease rapidly with depth, such that the saturation horizon is reached already at 130 m”
Clearly, both lakes and oceans stratify pH and pCO2 dissolution nearly instantly by temperature thermoclines, although the effect is less in the oceans due to much greater buffer capacity. Therefore, temperature dominates over well-mixed CO2 to control solubility and hence pH levels.


Next they will be worrying about ocean basification.
And if the oceans don’t change at all from humans, they will then worry about ocean stagnation, and that human activities have caused oceans to remain just too static.
Most coral reef researchers have long ago learnt that they can make up just about anything they like- underwater, out of sight, and non-verifiable means that just about any scare is plausible, on just about any timescale.


Coral reef researches are as ignorant today as they were 50 years ago … they have barely scratched the surface.


Coral reefs have survived for hundreds of millions of years, through many variations in sea temperature and ph. It is hubris to think that anything we do is ever going to kill of the corals.

It might be more logical to worry about basification with a pH of 8.1. But the general public knows what sulfuric acid (pH -2, I believe) will do to you and is frightened of acids. And as Streetcred pointed out, facts don’t matter anyway to someone whose mind is made up–even when they are intelligent.

citric acid in the eye can make you smart.

Jerker Andersson

I think we should not mix up what has happened during the last 280k years with what is happening now when it comes to CO2. While Henrys law says that a warm oceans can disolve less CO2 than a cold oceans it also says that if you increase the partial pressure of the CO2 in the atmosphere there will be an imbalance and the iceans will start to disolve CO2 from the atmosphere until a new equilibrium is reached. When that has happened both the oceans and the atmosphere has a higher amount of CO2.
If at the same time the temperature of the oceans increases as the CO2 is released into the atmosphere it becomes a bit more complex. In order for the CO2 in the oceans to increase at the same time as the the temperature increases the partial pressure of CO2 in the atmosphere must increas fast enough to outnumber the increased partial pressure in the oceans due to increasing temperature.
We know that roguhly half of the anthropogenic CO2 “stays” in atmosphere the rest is absorbed by earth’s different sinks where oceans are a major sink.
In order fo the oceans to be able to absorb CO2 from the atmosphere as is happening now, the partial pressure of CO2 in the atmosspere must be larger than the partial pressure in the oceans despite the oceans has warmed some in the previous deacades.

Nice fantasy. Problem is, the ocean is outgassing to the atmosphere.
The bottom of the ocean has liquid puddles and blobs of CO2. Yes, 100% concentated blobs of it.
Now think about it for a minute: 100% at one end, 400 ppm at the other. Which way does the CO2 migrate?
Has a nice bit of film of a shrimp swimming through a blob of CO2 liquid, too. (Didn’t hurt his shell…)
BTW, fresh water clams and other shellfish pretty much prove that shell formers can do fine in acid water. See, fresh water can be as low as 4 pH. And yet “they live”….
And don’t even get me started on the giga-tons of metals nodules on the ocean bottom. “Manganese nodules” that are really mixed metals. Can’t get to an acid pH until all THAT is reacted and dissolved…. i.e. not going to happen.

E.M., that the CO2 levels in the atmosphere are way higher than the equilibrium CO2 level between atmosphere and oceans is no fantasy. it is measured.
That there are CO2 emissions from undersea volcanic vents is right, but how much of that is reaching the surface and the atmosphere? Most is dissolved in the deep oceans, where that hardly influences the gigantic amount of carbon derivatives already present, as most is (by subduction) recycled sea floor carbonates.
The influence of increased temperature is +0.0114 pH unit per °C and an increase of ~8 μatm/°C. The increase in the atmosphere is ~110 ppmv, where humans emitted ~200 ppmv in the past 160 years. That gives a drop in pH of the ocean surface of ~0.1 ppmv. Far more (measured) drop than the (calculated) increase caused by the temperature increase since the LIA.
Agreed that the pH drop has zero practical effect on sea life, but one can’t use bad arguments to counter real knowledge where – for once – the AGW scientists are right…


E.M Smith, your objection to Jerker Andersson’s well reasoned post doesn’t square with matter conservation. If the anthropogenic CO2 emission are about twice as large as the rate of atmospheric CO2 increase (as they are), and the oceans also are a net source of CO2 outgassing, then where is the extra 50%+ of the total emissions (anthro+ocean) going?

“The influence of increased temperature is +0.0114 pH unit per °C and an increase of ~8 μatm/°C. The increase in the atmosphere is ~110 ppmv, where humans emitted ~200 ppmv in the past 160 years. That gives a drop in pH of the ocean surface of ~0.1 ppmv. Far more (measured) drop than the (calculated) increase caused by the temperature increase since the LIA.”
Reply: As shown by fig 1 above, a ~7C cooling is associated with a ~0.8 pH “acidification,” about an order of magnitude higher than you are claiming. Data trumps models, which is where your claims above arise, although as I’ve already pointed out, the effect will be less in the oceans due to buffering, but in the same direction with increasing temperatures, as demonstrated by this paper using ocean data:
“Ωarag and pH decrease rapidly with depth, such that the saturation horizon is reached already at 130 m, on average, but it occasionally shoals to as low as 30 m.”

Jerker Andersson is right. In the past, as stated in the paper, atmospheric CO2 and its balance with the oceans was all natural and the warmer = more alkaline relationship applied. But today, atmospheric CO2 has been increased by fossil fuel usage etc, and that pattern has been disturbed. It does seem clear that ocean pH has decreased very slightly in recent years, and that man-made CO2 is one of the factors. Doesn’t justify alarmism, though.

Tom in Florida

What is the amount of partial pressure increase of CO2 in the atmosphere? Is it consistent over all areas of ocean?

Besides the seasonal swings (+/- 8 ppmv in the Arctic to +/- 1 ppmv in the SH) and the lag of the SH (6-24 months), the increase is practical the same over all oceans: some 80 ppmv since the accurate measurements at the South Pole and Mauna Loa started.
There is also a small variation due to water vapor: a few % more water vapor (thus a few % less CO2 partial pressure) in the tropics than near the poles.
In general the differences in the atmosphere thus are small and practically negligible.
The differences in the oceans on the other hand are huge: the pCO2 of the ocean waters where the deep oceans are upwelling is way higher than in the atmosphere and where the heavy, salty waters sink near the poles, the pCO2 of the ocean waters is a lot lower, That makes that there is a huge CO2 flux between the equator and the poles via the atmosphere (and back via the deep oceans conveyor belt). See:

Robert W Turner

“It does seem clear that ocean pH has decreased very slightly in recent years”
Does it? That’s a major assumption. Ocean pH varies considerably with depth, temperature, biologic activity, season, diurnal cycle, and current. In some places it varies by well over 1 unit in a single day. How can you determine that the average pH of the surface of the ocean has changed by 0.1 units when we have very little data coverage, is naturally variable over short time scales, and the measurement of which is susceptible to errors?

Saw a paper studying pH in Santa Cruz harbor. It varied something like 1/2 to 1 whole digits day / night winter / summer based just on how much stff was busy doing photosynthesis, or respiration. Yes, they tracked it back to variations in sunshine and photosynthesis (how much of which plankton was doing what…) CO2 not so much.

There are four stations where ocean waters were sampled over longer periods and a lot of regular and irregular sea ships measurements where pH was sampled over different periods. Besides upwelling zones and coastal waters around river mouths which show high variability, the pH drops everywhere. Here for Bermuda:
and here for Hawaii:
The latter compared to Mauna Loa CO2 levels:
The pCO2 increase is higher in the atmosphere than in the oceans thus the flux is from the atmosphere into the oceans, which causes the pH drop…

Study shows modern oceans are more alkaline than past 250 million years…the modern ocean pH of about 8.1-8.2 is the most alkaline the oceans have been over the past 250 million years:
Ferdinand claims on the basis of only 4 measuring points in the global oceans “the pH drops everywhere.”
Why don’t you mention the Monterey Bay data back to 1995, which shows no trend and high variability at least 3 times greater than the alleged 0.1 pH change since pre-industrial times?

Gary Pearse

Mike, the pH varies quite widely depending where you take seawater samples.

Not so fast…
To begin with, the pH of a fresh water lake can’t be compared to the pH changes in the oceans. pH changes in fresh water are highly dependent of CO2 concentrations, but also of the rock composition where the rainwater is flowing in the catchment area. In general, the pH changes can be huge.
The pH changes in seawater are very small, even with huge changes in CO2 and temperature, thanks to the buffer capacity of the oceanic dissolved bi/carbonate salts.
There is no contradiction between increasing pH from increased temperatures and decreased pH from increased CO2 in the atmosphere, all depends of the magnitudes.
The direct influence of temperature on the oceans pH is about 0.0114 pH units per °C. As 1°C is about the maximum warming since the LIA, that is all what can be expected of warming oceans. See:
The solubility of CO2 in seawater decreases with higher temperatures. Not sure if that this is included in the pH change, but the equilibrium with the atmosphere increases with 4-17 ppmv/°C, depending of the source. Anyway, the historical equilibrium was ~8 ppmv/°C. Thus the increase of CO2 in the atmosphere would be ~8 ppmv for the temperature increase since the LIA.
The increased pressure of the 30% increase of CO2 in the atmosphere results in a 3% increase of total CO2 (DIC) in the oceans surface layer. That results in a drop of around 0.1 pH unit: about 100 times more in H+ concentration than the influence of the increased temperature…
With a decreased pH and higher temperatures, DIC decreases due to outgassing of CO2. With increased CO2 in the atmosphere, DIC increases and pH drops. The latter is what is observed in all ocean surfaces. See e.g. Fig. 5 in:
Thus the influence of the CO2 increase in the atmosphere on the oceans surface layer pH is way higher than the influence of increased temperatures…


Sorry Ferdinand, it just won’t do. It is as Viscount Monckton wrote – “ocean “acidification” is the last refuge of the global warming scoundrel.”
Why “acidification” as opposed to the more accurate “de-alkinisation”? Because “acid” sounds ever so much scary, doesn’t it? You and yours chose propaganda over science and were fool enough to do so while the Internet kept a permanent record.
There can be no forgiveness. Not now. Not ever.

Konrad, please see what I wrote: I didn’t use “acid” or “acidification” once. I used pH which is a neutral word and accurately described what happens.
Warmer means higher pH and lower DIC (dissolved inorganic carbon = free CO2 + bicarbonates + carbonates). Higher CO2 in the atmosphere means lower pH and higher DIC.
I never said that the small reduction of pH has or will have any influence on ocean life. To the contrary, coccoliths (chalk bearing plankton) thrived enormous during the Cretaceous with CO2 levels 10-12 times higher than today, still visible in the chalk rocks of SW England and many other places on earth…
But skeptics too should use the right arguments based on science not on what they like to hear…

You used the key phrase: “surface layer”. Your pH change only applies to a minute fraction of the oceans due to segregation of surface waters from deeper waters, ocean turnover being a very slow process.
Overall change of ocean pH is negligible, it seems.


You were right, you used “Ph” not “acidification”. I was wrong to write “you and yours”.
I would agree with your statement –
“I never said that the small reduction of pH has or will have any influence on ocean life. To the contrary, coccoliths (chalk bearing plankton) thrived enormous during the Cretaceous with CO2 levels 10-12 times higher than today”
The paleo CO2 record combined with fossil record can de-bunk the “ocean neutralisation” scare where this freshwater lake study will not.
You have extensive knowledge of past CO2 concentrations. Big Wind desperately needs CO2 to be the demon and they have millions to spend on “ocean neutralisation” propaganda now the warming thing has failed. I apologise for lumping you in with the “acidification” alarmists, but please use your powers for good, not evil 😉


@ Ferdinand Engelbeen
Hi Ferdinand.
Very good explanation of the oceanic pH drop.
Let me tell you first that I myself know no much about the physical processes related to oceanic pH.
But simply by looking and reading your above comment I can’t fail but “see” that you reach most probably a wrong conclusion by exagerating the warming of the oceans and the cause of that warming based in the certainty of AGW.
If AGW true and the warming at 2.5C (or more) for a doubling considered as of high probability then your explanation could be considered rational enough, but when all the possibilities considered actually the opposite seems more probable.
First flaw (the most significant one) you have in your argument is that you imply that the maximum 1C Warming since LIA is due to CO2 and then without any concearn at all make that observed atmospheric warming seem as an oceanic warming. As far as I am concerned there has been no any anomaly of warming detected in the oceans, appart from the assumption that in an AGW THE OCEANS SHOULD BE WARMING.
Second the 1C warming you refer to is not even in the most extreme scenario of AGW (3C CS for a doubling) all due to CO2, ……….0.2C-0.3C of it is due to other than CO2, most probably due to oceans and the
Oceanic-Atmosphere heat exchange as a result of LIA.
When oceans do warm the cool atmosphere the oceans lose heat.
So, for the first part of the 1C warming of atmosphere the oceans most probably did cool instead of warming.
Also considering the long term climatic trend the oceans have cooled during the last 6K years and to claim that oceans are warming you need a very good and undisputable evidence and data…. not just assumtions due to some thesis.
The problem with your argument becomes even more significant while we have to start considering that even the other part of the warming 0.7C to 0.8C is not entirely wholly due to CO2 emissions.
Whatever amount of warming not due to CO2 could be considered as due to oceans.
With that in mind for any CS below the 2C mark the oceans have cooled further…. and if you see closely the way your argument about how CO2, pH and oceans temp related then not difficult to conclude that the observed pH pattern of the oceans means that the oceans have cooled instead of warming…. making a case against AGW even more significant. At 1.3C and below CS that will hold as quite a good case against AGW.
As I said I know no much about oceans pH and the relation between it and CO2 + temp… but non the less, as far as I can ‘see’, still the flaws in your argument stand and actually point to a further point made against AGW…..provided that the flaws will be corrected as the case should be.
All sometimes depends only how you approach a given issue in relation of climate change…….AGW or natural…… the priority I think should be the natural approach and if that failing or in case of it not as rational as the AGW then no problem on jumping to see it as not natural………but trying to approach any given issue or problem only through an AGW angle and with total disregard and with contempt agains natural causes and natural variations tells a lot.

whiten, I didn’t assume that the temperature increase since the LIA has anything to do with CO2. In my opinion it is largely natural and a (very) little part from the increase of CO2 in the past 160 years.
But that doesn’t change the fact that the influence of ocean temperatures on pH and CO2 levels in the atmosphere is completely dwarfed by the CO2 increase in the atmosphere which is much higher that what the temperature may do. To reach the CO2 levels in the atmosphere, you need an ocean temperature increase of ~12.5°C. To perform the (measured/calculated) lower pH, you need ~8°C cooling of the ocean surface temperatures, which are opposite to each other to explain what is really happening…


your fine calculations do not convince. I have made this comment before, but you present your theories as established fact. Do you admit that the carbon cycle is not perfectlt understood?

I use established facts where they are appropriate:
If you heat a (bi)carbonate solution, some CO2 will get out of the solution and the pH will increase. That can be (and is) measured. That also can be calculated for any seawater solution.
If you increase the CO2 pressure in the atmosphere above the equilibrium pressure for a given temperature, the extra CO2 in the atmosphere will get into the solution. That can be (and is) measured and can be calculated for any seawater solution.
That has nothing to do with the carbon cycle, only with physics…
In this case, the effect of the increase in the atmosphere is far higher than of the increase in temperature, both theoretically and measured…
But I agree that the carbon cycle is by far not known in all details…

Jaakko Kateenkorva

Ferdinand. If laboratory scale experiments and equations are automatically applicable at Earth scale, would you then agree that ideal gas law (pV=nRT) is too?
The atmospheric volume (V) is far from constant and is still poorly understood.
We know even less about the ocean floor. The chances are that the amount of carbonate (n) in the sediments dwarf that dissolved in the oceans – let alone the anthropogenic CO2 in the atmosphere.
For these reasons I currently find anthropogenic CO2 partial pressure (p) driven ocean pH about as convincing as mass creation by pressure increase.

Jaakko, the pCO2 and pH measurements are not only from laboratory experiments (which did give the base for the calculations), but also from now near 7 million field measurements on sea ships and several fixed stations and moorings. Sea ship measurements are more and more extended to commercial vessels with the availability of automatic, maintenance free, accurate (solid state and micro spectrophotometric) pH measuring devices.
Of course carbon chemistry is far from known in all details, but what we know is that the exchanges between atmosphere and ocean surfaces are fast (1-3 years), but the exchanges with the deep oceans are quite slow (thus including the sea floor carbonate deposits) due to the limited exchanges between surface and deep oceans.
Simply said: the ocean surface follows the changes in the atmosphere almost immediately, where the changes are far larger and faster than what the rest of the natural carbon cycle can compensate for on short time scales…


Ferdinand Engelbeen
October 21, 2014 at 5:51 am.
You say:
“whiten, I didn’t assume that the temperature increase since the LIA has anything to do with CO2. In my opinion it is largely natural and a (very) little part from the increase of CO2 in the past 160 years.”
Hello again Ferdinand.
I did not say you assumed (as for above) I said you implied…and I tried to explain that by telling you that the 1C of atmosphere warming will be considered as warming somehow the oceans only if in the case while all of it due to CO2, because otherwise it could mean the opposite, the cooling of the oceans.
You also say:
“But that doesn’t change the fact that the influence of ocean temperatures on pH and CO2 levels in the atmosphere is completely dwarfed by the CO2 increase in the atmosphere which is much higher that what the temperature may do.”
You see, that is exactly why I did reply to you. The very opening of my previous reply to you:
” Very good explanation of the oceanic pH drop.”
I really meant it, is no sarcastic, because the main and central point in your comment as the above (selected from your reply), sounds rational to me and valid…I like it.
But I think that you fail to see that actually that central point in your argument does bebunk the certanty of Oceanic Ph drop due to only warming and Agw.
Also the entirety of your comment does contradict that by the very certanty approach you try to imply by assuming that a warming of atmosphere definitely means a warming of oceans.
You actually introduce a no certanty explanation and then you end up contradicting the whole point by very arbitrarely making a case of further certainty in support of AGW.
You see my reply to you does not contradict the main point in your argument….. but you your self do.
In any case I approached it with the possibility and probability angle…..while you did not…….and that was the main point in my previos reply to you…
Hope you understand this…..
Thanks again for the reply.
Sorry it tuck some time for me to reply to you again….was out of touch with internet till now..:-)

Robert W Turner

Changes in pH are negligible. The oceans are buffered and they have an endless supply of salts. The rate of weathering of rocks on the surface is proportional to temperature and rainfall. This acts as another negative feedback in the big picture. The last estimate for the total dissolved sediment load delivered to the oceans each year was something like 2*10^13 kg but estimates are generally increasing as we gather more data.


But the ocean doesn’t reach this new equilibrium instantaneously. If CO2 in the atmosphere changes more rapidly than calcium carbonate compensation, pH will go down.

“But the ocean doesn’t reach this new equilibrium instantaneously. If CO2 in the atmosphere changes more rapidly than calcium carbonate compensation, pH will go down.”
Buffering is a chemical reaction and for all intents and purposes of this discussion happens essentially instantaneously, far faster than pCO2 changes.
Buffering dominates temperature and then temperature dominates pCO2 levels to determine pH, both of which effectively debunk the “acidification” scare.
“The oceans are buffered and they have an endless supply of salts”
Correct, the oceans have more than enough buffering capacity even if all stores of fossil fuels were burned.

Thank you Ferdinand, for this much needed corrrection to an article with an unfortunate low level of correctness.


Basic physics definitely holds but on the other hand we can’t simply dismiss almost 30 years of measurements because of this single paper. The fact that dissolution of CO2 in seawater has grown (slightly) over that period and pH has decreased (slightly) over the same period is not a model, it’s data. Clearly, the sea did not warm up enough to completely counteract effect of increased atmospheric CO2 concentrations. And ironically, lower climate sensitivity to CO2 implies stronger effect of increased atmospheric CO2 on seawater chemistry.
It might be interesting to estimate development of seawater pH (or at least CO2 content) as a function of CO2 concentrations assuming different values of climate CO2 sensitivity. Such graph might provide a lot of material for thought.


” The fact that dissolution of CO2 in seawater has grown (slightly) over that period and pH has decreased (slightly) over the same period is not a model, it’s data.”
Do you have any references for that? I ‘ve been unable to find anything but modelling studies.


For instance this:
I may not like their conclusions but I don’t think they falsify the data.
If you want access to primary source, you can start here:

In addition to what Kasuha provides with the BATS (Bermuda) graph of increasing DIC/reducing pH, here a similar graph from the ALOHA (Hawaii) series:
Figure 1…
Repeated (sea ship) measurements over all oceans show the same trends over time…


Not true. See Takahashi, et al. (2009) Fig 1(B). There aren’t enough measurements to provide full seasonal coverage except in parts of the North Pacific and the parts of the Atlantic. Almost half the ocean areas have only about 3 months (per year) worth of data. There is no data whatsoever for part of the South Pacific. There isn’t enough data to say that ocean pH has decreased over the last 30 years. There is an estimate that it has, but I doubt that it is statistically different from zero, due to lack of data.
On page 9,

Because of insufficient sampling, the rate for the Indian and South Atlantic Oceans as well as for large areas of the South Pacific cannot be assessed satisfactorily as yet. … Furthermore, the rates for the remaining 73% of the ocean areas are not available.

Takahashi, et al. (2009) is referenced in AR5 and is the latest info. When data is not available for “73%” of the world’s oceans, any statements about ocean acidification rates are fabrications.

Phil, if there are sufficient data for 25% of the oceans which all show a declining pH for increased atmospheric CO2 even with increased temperatures and there are zero indications of the opposite trend, why shouldn’t you simply accept that the atmospheric increase of CO2 causes more pH drop than the temperature increase caused a pH increase? The more that such a drop is theoretically defendable: the pCO2 level in the atmosphere increased everywhere and the temperature increase is very modest in all oceans…

Gary Pearse

How much warmer were the oceans during the climate optimum? How much warmer the oceans during the Eemian interglacial, or the Mesozoic? How much lower the pH. How much higher the CO2 in the atmosphere? How much danger did the shell fish and living reefs live in during these changes? Finally, how much should we be worried about 400ppmv CO2 and/or 1-2C warming’s effect on today’s oceans? The former questions answer the last question for you.


Physical Chemistry dictates that you can’t have both unless the lower atmosphere is confined (which it isn’t) to a fixed volume. It is one of the first principles taught in secondary level elementary science.

You can have both if the seawater temperature increases and the partial pressure of CO2 in the atmosphere increases more than the increase caused by temperature, which is largely the case…


As others have said, the amount of CO2 which can be dissolved in water depends not only on temperature but also on the partial pressure of CO2 above the water. If the temperature is held constant and the CO2 concentration of the air increases then more CO2 will dissolve.
CO2 levels have increased since the pre-industrial era by about 40%. This massively outweighs any increase in ocean temperature (about 0.3%). Consequently, the alkalinity of the oceans should have reduced.
The Japanese paper also makes it clear that “the water pH in Lake Biwa is determined by phosphorus and alkali cation inputs”.
The Hockey Schtick interpretation of this paper conveniently ignores the increasing CO2 concentration and so arrives at an unsupportable conclusion as always. So be wary of repeating their claims that “these findings completely contradict the basis of the CAGW ‘acidification’ scare”.


“Not so fast…” indeed – claiming that a study of pH changes in a freshwater lake proves or disproves anything at all wrt so-called “ocean acidification” is very reminiscent of warmist “tricks”, and has no place on a truly sceptical blog. Citing Henry’s law is also invalid, as sea-water chemistry is complex, and pH is heavily buffered.

Anthony –
this paper would seem to be largely irrelevant to the bigger picture – tells us basically nothing. Nothing is ‘debunked’ here.
The physics says, yes, pH will increase marginally with increasing water temperature, but only assuming ppCO2 remains constant.
What might be more interesting than the near-impossible task of measuring ocean pH changes over time DIRECTLY, would be to look at actual carbonate concentrations over time . I don’t know whether useable data exists for this, and I would expect large local and depth-related variations, but may be better related to the biological response, especially the productivity of carbonate-skeleton organisms, which I assume is largely what is behind ‘acidification’ worries.
Perhaps someone with knowledge of it could also tell us about the scale of the buffering effect from ?carbonate rocks and how it relates to the book-value pH change from CO2 increase.


Is everyone discounting the observed lag in the temp/CO2 relationship?

Bloke down the pub

It’d be interesting to know what the flora was like in the region of Lake Biwa. How much of the change in Ph from summer to winter is due to dumping tons of rotting leaves into the water?

“Thus the influence of the CO2 increase in the atmosphere on the oceans surface layer pH is way higher than the influence of increased temperatures…”
I agree with Ferdinand. Paleo variations are not a guide to the present. Ocean acidification is not due to warming (which indeed would on its own raise pH) but to the direct injection of about 400 Gtons of C of fossil origin into the air as CO2. That is a unique event in paleo history. Something like half that 400 Gt has gone into the oceans. That dwarfs any temperature forced change.


“That is a unique event in paleo history.”
Depends on your time horizon. During PETM 55 million years ago about 5000-10000 Gtons C (possibly more) was dumped into the atmosphere in a geologically extremely brief time period. And there is strong evidence in the d14C record that very large amounts om CO2 (>100 GT) was dumped into the atmosphere just before the Younger Dryas. However that almost certainly came from the oceans.


Your assertions have a bald aspect. There is no conclusive evidence for any of this.


Nice try Nicky baby, but it won’t wash. You used the term “ocean acidification” as opposed to the correct phrase “ocean de-alkalinisation”. You have failed. Your shame is now a matter of permanent record. Enjoy! And remember –
“sceptics never forgive and the internet never forgets.”


@Konrad: Nice to see you stepping up over the truly serious issue of word choice, rather than the utterly benign one of Steve/Anthony using an utterly unrelated paper to prove their position — in this case, the use of a single paper addressing the paleo Ph of a SINGLE (freshwater) LAKE in Japan to “debunk” the claim of climate-related “acidification” (their word, not mine) in the OCEAN BASINS (plural, salt water) of the ENTIRE WORLD.
Seriously, who cares whether the paper under discussion is even related to the subject, let’s instead haggle over whether commentators should use (the completely nonsensical) ‘acidification’ vs. (the linguistically ridiculous) ‘de-alkalinization’, shall we? THAT ought to advance skepticism and the scientific method. /sarc
OH, and @Anthony/Steve: With all due respect, gentlemen, you must be better than this. Seriously. I’m not saying don’t link to the study, I’m simply saying don’t make the headline sound like someone just found the actual gun used to kill JFK, Bigfoot, the Mothman, AND the entire CAGW position. At least read the paper first, THEN come up with a title that actually applies.
[Note: this is not the erstwhile WUWT ‘Smokey’. ~mod.]

Silly – just semantics.
We say ‘cooling’ even when it’s hot, but is getting less hot,and ‘warming’ when it’s cold, without references to a definition. The term ‘acidification’ is not prejudicial and is more accessible than ‘de-alkalinisation’. Give the guy a break!


I know exactly what you mean. Last winter at one point it was cold where I lived. I mean REALLY cold. It didn’t get above 0 deg F for several days in a row. In other words, it was so cold that it could never be confused as being warm. And yet, when I got to work, one of my coworkers commented that it was supposed to get “warmer” the following week. Obviously, as you would no doubt agree, he must be a moron to have said that, since the correct phrase would have been “atmospheric de-coldification”.
From a standpoint of the language of chemistry, this use of acidification is perfectly reasonable.


You may claim my objection to “ocean acidification” is just semantics and won’t advance skepticism and the scientific method. The point is to counter propaganda. Smokey is right to say de-alkalisation is no better, but the fact remains “ocean acidification” is a propaganda term pure and simple.
It is physically impossible for atmospheric CO2 to make the oceans acid. As many have pointed out on this thread, the buffering both mineral and biological is too great. All that could possibly happen is the oceans could become very, very slightly less alkaline. If the oceans cannot become acid, then the scientifically correct term should be “ocean neutralisation”. The fact is that “acidification” was chosen because it sounds far more scary.
In this case words do matter. This is just a “back up scare” by the CO2 doom shriekers. It is weak, and easily countered by geological, fossil and paleo CO2 records. It’s survival is highly language dependant. If sceptics all correct with “ocean neutralisation” every time they see “acidification” used online the scare will be “neutered”.
And further on why words matter, this weak back up scare is only being trotted out because of words. In particular “CO2” and “carbon”. The demonisation of CO2 has been so thorough that all the fellow travellers are now wedged. They can’t back down on their CO2 = doom “narrative”. Big Wind subsidy farmers in particular are utterly compromised if CO2 is not demonised. They have millions to spend on propaganda now the anti shale gas propaganda attempt failed. Sceptics repeating just two words, “ocean neutralisation”, can defeat as many millions as Big Wind wishes to throw at CO2 propaganda.

“Paleo variations are not a guide to the present. ”
except when you wish them to be so.


Something like half that 400 Gt has gone into the oceans.

We don’t know that. That is an estimate. When there is insufficient data to calculate surface pH change rates for 73% of the world’s oceans, you cannot make a categorical statement like that. See my comment above.

Phil, there are far more pCO2/bi/carbonate measurements done in the past and present than pH measurements of the seawaters (both surface and depth). See:
Further, what goes into the biosphere (plants) is calculated via the oxygen balance: about 1 GtC/year of the ~9 GtC/year human emissions (as mass, not original molecules) and growing. ~4.5 GtC/year remains in the atmosphere, 0.5 GtC/year goes into the oceans surface and the difference should go somewhere. If not in the deep oceans, where should it go, as all other known sinks are either too small or too slow…

Ferdinand Engelbeen:
“as all other known sinks are too small or too slow”.
We do not yet have adequate understanding of the carbon cycle, nor of sinks nor sources, and you say you agree, yet you continue to make positive assertions like above.
What is your source for your claim that surface pH has decreased 0.1?

Mpaiinter, not all details of the carbon cycle are known, but the overall balance is well known: 9 GtC in, 4.5 GtC out, 4.5 GtC into the atmosphere.
For the oceans surface, the exchanges with the atmosphere are quite fast, thus whatever the changes in the atmosphere, the ocean surface will follow (or vice versa).
CO2 increases with 4.5 GtC/year in the atmosphere, that makes that the ocean surface layer increases its total carbon content (DIC) with ~0.5 GtC/year, due to the Revelle/buffer factor. That is pure seawater (buffer) chemistry and is confirmed at several fixed stations and by sea ship measurements.
If the temperature increase of the oceans was dominant, the warming would increase the pH and decrease DIC. If the CO2 increase in the atmosphere was dominant, the pH will get lower and DIC in the surface will increase.
If you look at the data provided for the stations at Hawaii and Bermuda (or any time period for sea ship measurements for the same area), you will see that a 10% increase of CO2 in the atmosphere resulted in a 1% increase of DIC over the period of measurements and a drop in pH. Thus the increase of CO2 in the atmosphere is dominant. That can be extrapolated to the past, as the atmospheric levels are known from ice cores. The figures also can be extrapolated to all ocean basins, because the CO2 levels in the atmosphere are practically the same everywhere and ocean chemistry is that too (except near estuaries and near upwelling zones).

Gary Pearse

This is all ceteris paribus stuff. How many of you are aware that calcium carbonate behaves somewhat like CO2 – it is more soluble (dissociates) at colder temperatures and higher pressures and there is a heck of a lot more of this stuff in the oceans than there is just gaseous CO2. Moreover, although carbonate solubility is higher in acidic solutions, it still dissolves to a small degree even at pH of 12! (about 1% of that at pH 6). This looks small but the amount of carbonate is very large. This solubility may well be required for corals and shellfish to be able to calcify themselves although I will defer to an honest invertebrate zoologist on this.
To complicate things further, the solubility of calcium carbonate increases quite strongly with increased salinity, don’t ya know. It’s solubility is almost zero in freshwater so it wouldn’t be a factor in the Lake Biwa case – this may be the biggest factor in disqualifying the Japanese work’s application to seawater. Frankly, there is so much going on the sea chemically and on such a mind boggling scale (including Chiefio’s contribution on liquid CO2 lying in puddles in the ocean depths and pluming through seeps in the ocean’s submarine ridges from below), that tidy reactions and Henry’s Law are not fit enough for purpose. We just don’t know this stuff. What we do know is that adding a 100 -200ppm of CO2 to the atmosphere is pretty puny by comparison.

Gary Pearse

Unfortunately this has absolutely no relevance for “ocean acidification”. The chemistry of freshwater lakes is very different from oceans.

michael hart

Yes. Fresh water should, in principle, register larger pH swings because it doesn’t have the buffering capacity. Of course there is no evidence that CO2 is causing any problems in these systems either, but that’s not normally considered a issue by the modelers.
There is, in any case, insufficient data and knowledge to model it effectively, so one can see why they don’t bother trying.

This paper is about a lake. It tells us very little about processes in the oceans. The Japanese lake is eutrophic, meaning the nutrients entering the lake from the land promote photosynthesis which in turn increases the pH of the lake.
Eutrophic processes are known in the oceans mainly near coasts. But many regions of the world ocean are oligotrphic, meaning deficient in nutrients needed for photosynthesis, often iron. Some regions of the oceans are so deficient in nutrients (ultraoligotrophic) that there is little photosynthesis the pH is falling.
When you look at the issue of ocean acidification you find that the oceans are actually quite alkaline.
Surface waters of the oceans have been acidified by an average of 0.1 pH units compared with pre-industrial levels (Doney, 2010). Model simulations predict that ocean pH will decrease by 0.2 to 0.3 pH units by the end of the twenty first century (Demetris Kletou and Jason M. Hall-Spencer, 2012).
These changes may not be as significant as these authors claim because the average figure masks big regional differences.
The areas where pH is falling most are large while areas where pH is rising are small. The average figure estimated by models may seem threatening but this may be deceptive. Areas where pH is falling can lose little marine life because there is so little marine life there to be lost. By contrast in areas where pH is rising marine life is relatively abundant and has the potential to increase because of the presence of nutrients. .
Reference: Demetris Kletou and Jason M. Hall-Spencer (2012). Threats to Ultraoligotrophic Marine Ecosystems, Marine Ecosystems, Dr. Antonio Cruzado (Ed.), ISBN: 978-953-51-0176-5, Available from:
Oceanic pH is a complex subject that cannot be explained by reference to lake pH.
Dr Murray Salby has pointed out that CO2 flux between the atmosphere and the ocean is about 50 times the net CO2. (Net CO2 is difference between CO2 outgassed from and CO2 dissolved in the oceans )
Since CO2_out minus CO2_in is so small, the error in measurement does not the net amount to be measured with certainty. For this reason I regard the paper by Kletou and Hall-Spencer to be unduly alarmist.
I regard the paper re the Japanese lake to be interesting but totally irrelevant to global warming.


Surface waters of the oceans have been acidified by an average of 0.1 pH units compared with pre-industrial levels (Doney, 2010).

Thank you for the reference. I have been looking for it for a while. pH wasn’t defined until the late nineteenth century and the first pH meter wasn’t built until the 1930s, IIRC. Doney, 2010 on page 4 states the following:

From preindustrial levels, contemporary surface ocean pH has dropped on average by about 0.1 pH units (a 26% increase in [H+]), and additional declines of 0.2 and 0.3 pH units will occur over the 21st century unless human CO2 emissions are curtailed substantially (28).

Reference (28) is J. C. Orr et al., Nature 437, 681 (2005), of which Doney is a co-author.
On page 2, Orr et al. (2005) state:
We have computed modern-day ocean carbonate chemistry from observed alkalinity and dissolved inorganic carbon (DIC), relying on data collected during the CO2 Survey of the World Ocean Circulation Experiment (WOCE) and the Joint Global Ocean Flux Study (JGOFS). These observations are centred around the year 1994*, and have recently been provided as a global-scale, gridded data product GLODAP … We also estimated preindustrial [carbonate ion concentrations] from the same data, after subtracting data-based estimates of anthropogenic DIC (ref. 17) from the modern DIC observations and assuming that preindustrial and modern alkalinity fields were identical (see Supplementary Information).
*Takahashi, et al. (2009) with much more data still states that

rates for … 73% of the ocean areas are not available.

The Supplementary Information references “preindustrial” concentrations, but has no explanation of the calculation.
Looking at Orr et al. (2005) again, on page 1, it states:

Surface ocean pH is already 0.1 unit lower than preindustrial values.

No further explanation is given and no reference is made. Unless someone can come up with another reference, it would seem that the entire myth that there has been a decrease in ocean pH of 0.1 since pre-industrial times is based on a single unsupported assertion with no explanatory calculation. As with most things that I have seen with Climate Science, when you dig down to the foundations to find out on what some unquestioned piece of scientific lore is based, all you come up with is mush. Ocean Acidification and the belief that there already has been a decrease in ocean pH of 0.1 since pre-industrial times is accepted as gospel by huge numbers of people, policy makers, NGOs, scientists, etc. etc. etc. Sigh.

Thanks, Phil, you convince. Ferdinand has a few things to learn about verifying claims.
A 0.1 increase in pH turns out to be utter fabrication. Thanks, again.

As said before, if there is sufficient data for 25% of the oceans which all confirm the theoretical trends, I don’t see any reason why that may not extrapolated for the total oceans, as all oceans obey the same physical/chemical rules and CO2 levels in the atmosphere increased everywhere and the effect of ocean temperature increases are very modest in all oceans.
Of course, if you have any indication that there are opposite trends in any open oceans (not coastal or at upwelling areas), I have no problem to change my opinion…

Decrease, rather.

Evan Jones

I have not so far questioned acidification much. But I have given it a game-designer/developers’ five-minute assessment. A top-down assessment, if the lords and ladies will permit. (I have also corresponded with NESDIS on the matter. Nice people, and, for my purposes, straight answers noting uncertainties and unknowns.)
So let’s look at the very basics we know (or presume) so far:
Duration: Since ~1750
“Measurable” CO2 increase: Since 1850
Amount: of acidification asserted: ~30%
Mechanism: biota absorbs the CO2 and outputs carbonic acid.
Concentration: Along the coasts.
CO2 sink down to biota level: ~1800 Bil. Metric Tons Carbon
CO2 sink, total oceans: ~ 43,000 BMTC
CO2 Input (net): ~2+ BMTC per year.
CO2 outtake: -2 BMTC to calcification.
Total accumulated excess CO2: ~ 10%
I confirmed from NESDIS that drainage, dumping, and dredging will cause carbonic acid production in much the way CO2 does: it feeds the biota and the output is carbonic acid. That would explain the early start date and also the rate of acceleration. (They have not, as of yet, explored this avenue, however.)

Peter Miller

At the end of the day, if you do the maths, you will find at the current rate of CO2 absorbtion, the CO2 absorbed by the oceans will be approximately one part per million parts of water over the next century.
While I believe the alarmist scare about ocean acidification to be complete BS, I see this paper as having serious flaws. Changing rainfall patterns would change lake pH and also affect the amount of metal ions in solution. Also, it assumes no net additional CO2 is added to the atmosphere, such as man is doing today. A lake is a closed, fresh water environment, an ocean is an open salt water environment.

Evan Jones

Some of it is converted to carbonic acid by various biota. And we do need to consider that the top layer (down to biota) is the schwerpunkt here. That subsink contains ~1800 ppm BMTC, as opposed to the 43,000 BMTC of the oceans entire. ~2 BMTC accumulates annually in that upper layer. Nothing to panic about, but we do need to keep an eye on it, I think.


As others have noted, the headline is very misleading and inaccurate. The link to possible ocean acidification is very unclear and certainly not mentioned explicitly by the authors. The thrust of the paper is the link or ordering of temperature changes and precipitation changes over thousands of years.
One interesting result is the apparent non-catastrophic impact of variations in pH levels in lake water both seasonally and over thousands of years – though again I did not see this being directly addressed by the authors.


It’s up for grabs-
“While ocean acidification is well documented in a few temperate ocean waters, little is known in high latitudes, coastal areas and the deep sea, and most current pH sensor technologies are too costly, imprecise, or unstable to allow for sufficient knowledge on the state of ocean acidification..
The Wendy Schmidt Ocean Health XPRIZE is a $2 million global competition that challenges teams of engineers, scientists and innovators from all over the world to create pH sensor technology that will affordably, accurately and efficiently measure ocean chemistry from its shallowest waters… to its deepest depths’

Mark Bofill

OMG It’s worse than we thought, the oceans are becoming more alkalinic!
You can’t win that way, the warmist theory is that every change is bad, no matter how insignificant. The models say life is fragile and can’t deal with any changes, so the biosphere will always collapse.


Man-caused global cooling and ocean deacidiification will cause destruction of the human race. The shelled creatures of the sea will develop impenetrable shells causing the starvation of fish that feed on them. The only solution is to slow economic development and tax the bejesus out of anything with a job.

We now observe the latest front in the war on skeptics….”DEFEND THE DEEP OCEANS”… deep in the warmists’ command bunker the salient cry issues forth….”do not let them try to clarify the enormity or the utter lack of historic data that allows the latest theory about what happened to all that warming over the last 18 years to go unchallenged” The AGW crowd will fight to the death on this one… or at least until it becomes apparent to everyone that we actually have begun the descent of the Maunder Minimum… and of course at that point most of them will have retired on their cushy pensions…all guaranteed by their respective governments… while poor working class stiffs and small business owners suffer the increased costs in their energy purchases and all things related.


You touch on something that could make a positive impact toward getting the truth from government climate scientists – tie their pensions to the verity of their predictions. Multiply the pension money is James Hansen collecting right now by the percentage of actual temperature rise versus his predictions from back in 1988:
“If the current pace of the buildup of these gases continues, the effect is likely to be a warming of 3 to 9 degrees Fahrenheit from the year 2025 to 2050, according to these projections.”
So, given his average prediction is 6 degrees F from 1988 to 2037.5 or 0.67 C per decade, we should be 1.74 C warmer now than in 1988. Okay, the OLS trend since then (UAH) is about 0.4 C so Hansen’s pension should only be ~23% what it is.

It really doesn’t matter why you are frightened, the important thing is that you are frightened.


i never realized they settled the science on ocean geochemistry too. wow, they are amazing.

Kurt Hanke

It’s important to consider all effects on pH, and one that often gets left out is the effect that adding or removing dissolved oxygen has. When oxygen is removed from water the pH decreases. This might explain some of the more localized effects concerning ocean acidification. We have a grand experiment going on here right under the noses of the Seattle Times. Puget Sound has the equivalent of a mid-size supertanker full of raw sewage dumped into it each week by the good citizens of Victoria BC – the only major metropolitan area on the left coast still doing this. They claim that this is ok since they have filtered out most of the “floaties” (gotta love those Canucks). However if you look at what is dumped into the Sound, most of it will readily bind with oxygen, and given the volume will significantly lower pH levels in the area. The chemicals in ground water that drains into the Sound also do the same. There is anecdotal evidence of this as divers I have spoken to tell me the difficulties the deeper dwelling animals are having in getting enough oxygen. Puget Sound is quite deep in areas, and famous for the Octopi that live there. Because it is a confined body, it is insulated from dilution somewhat. Tidal action eventually pulls this more acidic solution out to sea, where it makes a left turn and goes down the coast. This is where the shell fish farms are that were highlighted in the Times focus on acidification and its effects. They never explained how it was possible for one of the farms to move to Hawaii and get relief. If acidification were caused by rising atmospheric CO2 levels, it would be more universal, and you would not be able to move to Hawaii to get relief. They also do not explain how the shell fish we are concerned about could have established themselves on this planet a million years ago, when CO2 levels were much higher than they are now. Why didn’t ocean pH wipe them out then?


The ignorance of the carbon cycle/buffering is amazing….

For those interested in the possible pH effects in salt water oceans, not a single fresh water lake, and also the scientific misconduct behind the Seattle Rimes utterly misleading series Sea Change concerning corals and oysters, read the essay Shell Games in the new ebook Blowing Smoke. The oyster part was previously guest posted at Climate Etc.


It seems a sensible conclusion that for a given CO2 concentration in the air, warmer waters will cause outgassing and thus increase pH.
However, how does the CO2 concentration in the water vary with increased CO2 concentration in the air? One would imagine that it increases.
So, with rising temperatures (not that we have been warming for 18 years) and rising CO2 concentration, there will be two competing factors at work to settle on the stable CO2 concentration and hence pH of the ocean – rising CO2 concentration in the air will tend to increase ocean CO2 levels and rising temperatures will tend to decease ocean CO2 levels.
Has anyone done any work to determine the combined effect of rising temp and rising CO2 concentration in the air?

Rising temperatures did give some 8 ppmv/°C over the past 800,000 years (ice cores). In the literature, the theoretical increase in ocean pCO2 varies between 4 μatm/°C and 17 μatm/°C, thus the 8 ppmv/°C equilibrium pressure (1 ppmv ~= 1 μatm minus the % water vapor present in the atmosphere) with the atmosphere isn’t far off.
The increase in the atmosphere is about 110 ppmv since ~1850. That is way above the ~290 ppmv equilibrium CO2 pressure for the current temperature. Thus the increase in the atmosphere is way higher than the equilibrium and more CO2 is pressed into the oceans. That is measured as an increase in total carbon (DIC) in the oceans and a decrease in pH.
[“DIC” is what “Dissolved ? Carbon” term? .mod]

800,000 years ago. right. you’ve got that certainty in your response that scares the living xxxx out of all of us. Tell me, is it going to rain tomorrow. Please tell me with such certainty that you know for a fact what the ppm of CO2 800,000 years ago was. Absolutely amazing.
And ladies and gentlemen come this way…. in this tent you can see the amazing draconica….she will bedazzle you with her ability to predict the future…. come and see the floods, the droughts, the tidal waves of destruction…

DIC = dissolved inorganic carbon = free CO2 + bicarbonates + carbonates
[Thank you. .mod]

I never try to predict the future, but one knows more about the past than you may realize.
Ice cores are quite reliable for CO2 levels: once the air bubbles are closed there is no measurable migration in the cold inland ice cores with the longest history. The only drawback is that there is a long period of open pores with the atmosphere which makes that the resolution varies between 10 and 600 years, depending of the snow accumulation rate, which is very high for coastal cores and very low for deep inland cores.
The 800,000 year Dome C ice core has a resolution of ~560 years and a repeatability of CO2 levels of ~3 ppmv (2 sigma). See:
The current increase of ~110 ppmv would be detected in all ice cores, including the worst resolution if that ever happened in the past in their period of measurement… Here the results of several cores over the past 1,000 years:

James at 48

I actually think there have been localized reductions in pH, most especially in places like the Gulf of Mexico, the East Coast of the US, and the coast of Asia. However, I suspect the culprit is ag run off and the carbon cycle has zero to do with it.

Ralph Kramden

reconstructs water pH and temperature from a lake in central Japan, is this a fresh water lake?
Dissolved CO2 reacts quite differently in fresh water than in salt water. Just thought I would point that out.

David in Texas

It doesn’t appear that this paper has any bearing on the so-called ocean acidification. Note: “Because the water pH in Lake Biwa is determined by phosphorus and alkali cation inputs.” There is no mention of CO2.


I’ve never heard so much garbage from a bunch of sock puppets in my life!
Comments about greenery dropping vegetation into the lake, rain water feeding into the lake, infused with minerals, hinting it is a sample of one lake so the laws of nature may not apply elsewhere and so forth.
I have one thing to say to anyone who thinks they are talking about a puddle.,+Japan/@35.3456394,135.3277006,8z/data=!4m2!3m1!1s0x60010acfc4ac3edb:0xee09cf98c31a940f
Another point about Henry’s law. Yes, CO2 has increased so you expect under Henrys law the CO2 levels to increase in respect in the lake… BUT so has temperature. The partial pressures of ph/temperature of water is well known.. Prove my assertion plain wrong.
Once again, people were bridling the horse backwards on the cart and not knowing their error..


You write
“The partial pressures of ph/temperature of water is well known..Prove my assertion plain wrong.”
Unfortunately nobody will be able to prove your assertion wrong because your “assertion” makes no sense. It is both linguistically and scientifically nonsense. It comes in that famous category “not even wrong”.
Ferdinand Engelbeen has a nice series of comments, some of which I’ve linked below. He is correct and what’s more Nick Stokes agrees with him, as do I.
Nick Stokes

Oh well, that settles it.


acementhead Ironically all your responses you timely and carefully covered have been answered. So there you go. You wasted your time by being flat wrong 😀 haha.
What in English does “not even wrong” assert? Then you say my assertion is incorrect.


Interesting to read through all of these comments and see that the idea of partial pressure equilibrium with the surface layers of the ocean is opposed like it was some sort of communist propaganda. Thanks to Ferdinand for his patience.

Thanks! I always wonder why people who call themselves skeptics are so violently attacking anything that may be right, if it remotely may support the AGW meme and accept without any skepticism what is said if that “debunks” the AGW theory…
I am as skeptic to both sides of the fence, which makes that I have friends and foes at both sides…

You are a skeptic? Fine, so am I.
What other natural processes lower ocean pH? And have you quantified these? I will wager the answer is no.

In addition, the paper shows that pH of the lake varied over a wide range from ~7.5 to 8.8 simply depending on the temperature of each month of the year. As the “acidification” alarmists like to say, a variation of 1.3 pH units is equivalent to a 1995% change in hydrogen ions due to the logarithmic pH scale, just over a single year!
Yes, 10^1.3 is ~20X increase in H^+ but that’s in fresh water, the buffering capacity of sea water is much greater hence the paper says nothing at all to debunk ‘ocean acidification’.
Peter Miller October 21, 2014 at 3:54 am
At the end of the day, if you do the maths, you will find at the current rate of CO2 absorbtion, the CO2 absorbed by the oceans will be approximately one part per million parts of water over the next century.

Sounds impressive until you realize that at a pH of 8 the oceans have 10 parts per billion of H^+ ions!

When the only variable is temperature, warming water reduces its CO2 content and its pH will rise. However, the concern over ocean acidification is from the most significant factor being increased concentration of atmospheric CO2. As concentration of a gas over a liquid increases, the equilibrium concentration of dissolved gas in the liquid also increases.


You’ve repeated this like so many and correctly. So tell, does the tail wag the dog?
According to that paper, no it doesn’t.

Of course, this paper is wildly “off message” so an unconnected press release (on the imminent threat to anglers due to the threat of reduced lugworm sperm count due to a model of ocean cuprification due to global warming) suddenly appears by the deadly duo BBC (Roger Harrabin, UEA Correspondent) and the UK Government Chief Scientific Adviser(Sir Mark Walport). Sir Mark Walport. They’re getting desperate!


This paper is a red herring. ““the water pH in Lake Biwa is determined by phosphorus and alkali cation inputs”. This means that the pH of the lake is not determined by atmospheric CO2, but by acids and alkalis washing into the lake. The pH history of the lake can therefore not tell us anything about the relationship between pH and atmospheric CO2, either of the lake or of the oceans. It may tell us something about the rainfall patterns and how they affect the flows of acids and alkalis into the lake. Hence “the record of water pH should indicate the changes in precipitation and temperature in central Japan”. Nothing about CO2.