Guest Post by Willis Eschenbach
I’m a long-time ocean devotee. I’ve spent a good chunk of my life on and under the ocean as a commercial and sport fisherman, a surfer, a blue-water sailor, and a commercial and sport diver. So I’m concerned that the new poster-boy of alarmism these days is sea-water “acidification” from CO2 dissolving into the ocean. Heck, even the name “acidification” is alarmist, because sea water is not acid, nor will it every be. What we are seeing is a slight reduction in how alkaline the sea water is.
There is a recent and interesting study in GRL by Byrne et al., entitled “Direct observations of basin-wide acidification of the North Pacific Ocean“. This study reports on the change in ocean alkalinity over a 15 year period (1991-2006) along a transect of the North Pacific from Hawaii to Alaska. (A “transect” is a path along which one measures some variable or variables.) Here is the path of the transect:
Figure 1. Path (transect) used for the measurement of the change in oceanic alkalinity.
I love researching climate, because there’s always so much to learn. Here’s what I learned from the Byrne et al. paper.
The first thing that I learned is that when you go from the tropics (Hawaii) to the North Pacific (Alaska), the water becomes less and less alkaline. Who knew? So even without any CO2, if you want to experience “acidification” of the ocean water, just go from Hawaii to Alaska … you didn’t notice the change from the “acidification”? You didn’t have your toenails dissolved by the increased acidity?
Well, the sea creatures didn’t notice either. They flourish in both the more alkaline Hawaiian waters and the less alkaline Alaskan waters. So let’s take a look at how large the change is along the transect.
Changes in alkalinity/acidity are measured in units called “pH”. A neutral solution has a pH of 7.0. Above a pH of 7.0, the solution is alkaline. A solution with a pH less than 7.0 is acidic. pH is a logarithmic scale, so a solution with a pH of 9.0 is ten times as alkaline as a solution with a pH of 8.0.
Figure 2 shows the measured pH along the transect. The full size graphic is here.
Figure 2. Measured ocean pH from the surface down to the ocean bottom along the transect shown in Figure 1.
The second thing I learned from the study is that the pH of the ocean is very different in different locations. As one goes from Hawaii to Alaska the pH slowly decreases along the transect, dropping from 8.05 all the way down to 7.65. This is a change in pH of almost half a unit. And everywhere along the transect, the water at depth is much less alkaline, with a minimum value of about 7.25.
The third thing I learned from the study is how little humans have changed the pH of the ocean. Figure 3 shows their graph of the anthropogenic pH changes along the transect. The full-sized graphic is here:
Figure 3. Anthropogenic changes in the pH, from the surface to 1,000 metres depth, over 15 years (1991-2006)
The area of the greatest anthropogenic change over the fifteen years of the study, as one might imagine, is at the surface. The maximum anthropogenic change over the entire transect was -0.03 pH in fifteen years. The average anthropogenic change over the top 150 metre depth was -0.023. From there down to 800 metres the average anthropogenic change was -0.011 in fifteen years.
This means that for the top 800 metres of the ocean, where the majority of the oceanic life exists, the human induced change in pH was -0.013 over 15 years. This was also about the amount of pH change in the waters around Hawaii.
Now, remember that the difference in pH between the surface water in Hawaii and Alaskan is 0.50 pH units. That means that at the current rate of change, the surface water in Hawaii will be as alkaline as the current Alaskan surface water in … well … um … lessee, divide by eleventeen, carry the quadratic residual … I get a figure of 566 years.
But of course, that is assuming that there would not be any mixing of the water during that half-millennium. The ocean is a huge place, containing a vast amount of carbon. The atmosphere contains about 750 gigatonnes of carbon in the form of CO2. The ocean contains about fifty times that amount. It is slowly mixed by wind, wave, and currents. As a result, the human carbon contribution will not stay in the upper layers as shown in the graphs above. It will be mixed into the deeper layers. Some will go into the sediments. Some will precipitate out of solution. So even in 500 years, Hawaiian waters are very unlikely to have the alkalinity of Alaskan waters.
The final thing I learned from this study is that creatures in the ocean live happily in a wide range of alkalinities, from a high of over 8.0 down to almost neutral. As a result, the idea that a slight change in alkalinity will somehow knock the ocean dead doesn’t make any sense. By geological standards, the CO2 concentration in the atmosphere is currently quite low. It has been several times higher in the past, with the inevitable changes in the oceanic pH … and despite that, the life in the ocean continued to flourish.
My conclusion? To mis-quote Mark Twain, “The reports of the ocean’s death have been greatly exaggerated.”
[UPDATE] Several people have asked how I know that their method for separating the amount of anthropogenic warming from the total warming is correct. I do not know if it is correct. I have assumed it is for the purposes of this discussion, to show that even if they are correct, the amount is so small and the effect would be so slow as to be meaningless.
[UPDATE] WUWT regular Smokey pointed us to a very interesting dataset. It shows the monthly changes in pH at the inlet pipe to the world famous Monterey Bay Aquarium in central California. I used to fish commercially for squid just offshore of the aquarium, it is a lovely sight at night. Figure 4 shows the pH record for the inlet water.
Figure 4. pH measurements at the inlet pipe to the Monterey Bay Aquarium. Inlet depth is 50′ (15 metres). Light yellow lines show standard error of each month’s measurements, indicating a wide spread of pH values in each month. Red interval at the top right shows the theoretical pH change which the Byrne et al. paper says would have occurred over the time period of the dataset. Photo shows kids at the Aquarium looking at the fish. Photo source.
There are several conclusions from this. First, the sea creatures in the Monterey Bay can easily withstand a change in pH of 0.5 in the course of a single month. Second, the Byrne estimate of the theoretical change from anthropogenic CO2 over the period (red interval, upper right corner) is so tiny as to be totally lost in the noise.
This ability to withstand changes in the pH is also visible in the coral atolls. It is not widely recognized that the pH of the sea water is affected by the net production of carbon by the life processes of the coral reefs. This makes the water on the reef less alkaline (more acidic) than the surrounding ocean water. Obviously, all of the lagoon life thrives in that more acidic water.
In addition, because of the combination of the production of carbon by the reef and the changes in the amount of water entering the lagoon with the tides, the pH of the water can change quite rapidly. For example, in a study done in Shiraho Reef, the pH of the water inside the reef changes in 12 hours by one full pH unit (7.8 to 8.8). This represents about a thousand years worth of the theoretical anthropogenic change estimated from the Byrne et al. paper …
The sea is a complex, buffered environment in which the pH is changing constantly. The life there is able to live and thrive despite rapidly large variations in pH. I’m sorry, but I see no reason to be concerned about possible theoretical damage from a possible theoretical change in oceanic pH from increasing CO2.
[UPDATE] I got to thinking about the “deep scattering layer”. This is a layer of marine life that during the day is at a depth of about a thousand meters. But every night, in the largest migration by mass on the planet, they rise up to about 300 meters, feed at night, and descend with the dawn back to the depths.
Looking at Figure 1, this means they are experiencing a change in pH of about 0.4 pH units in a single day … and alarmists want us to be terrified of a change of 0.002 pH units in a year. Get real.
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Willis,
What makes you say the pH change is human-induced? Jump to conclusions much?
You’ll note that the deep water, which by the way comprises 90% of all ocean water, has very little change over latitude and is substantially less alkaline than the surface waters. Isn’t it quite possible, or even likely, that the less alkaline depths are simply mixing more or less with the surface layer? Surely you know that there’s a vast oceanic conveyor belt that mixes the two layers. Do we know, other than coriolis force plus equatorial heating and polar cooling which are the main drivers, what factors serve to change the amount of mixing? Wind is one thing. If the warmists are correct that more surface heat creates more severe weather then we should expect a negative feedback as the winds cause more mixing of warm surface water with the almost freezing cold depths.
We know there are cyclical events like ENSO, PDO, and AMO with somewhat variable cycle times from years to decades. What drives the variability? To believe that a tiny fraction more CO2 in the atmosphere, which may or may not be due to human activity, is responsible is both unwarranted and unlikely. To believe such a thing with religious fervor and conviction is indicative of someone not playing with a full deck if you ask me.
Leonid Polyak of OSU’s Byrd Center (“History of Sea Ice” survey in QSR 2010) recently kindly referred me to two articles on pre-pleistocene CO2 atmospheric concentrations by Dana Royer et al, in GSA Today March 2004 (v. 14 no 3, p4ff), and (solo) in Geochimica et Cosmochimica Acta 2006 (v. 70: 5565-75, as providing a good summary of knowledge of pre-Vostok CO2 levels.
According to the estimates Royer cites, CO2 concentrations were in excess of 500 ppm and often in excess of 1000 ppm for most of the last 500M years. During much of the Paleozoic, the point estimates (with a huge error band) run about 4000 ppm, while the Mesozoic ran mostly 1000-2000 ppm (with a big error band). The only times it has been comparable to pre-1950 levels have been glacial periods — the Neogene and the late-Carboniferous-Permian glacials. Royer proposes 1000 ppm as being the threshold for “the initiation of globally cool events” and 500 ppm as the threshold for “full glacials”.
Of course it’s hard to separate cause and effect — do fluctuations in CO2 (due to vulcanism, weathering, and fossil fuel and limestone formation) cause fluctuations in temperature through the GHG effect, or do fluctuations in temperature (from orbital, solar, and other causes) cause CO2 to be outgassed from the oceans?
But be that as it may, most of the world’s limestone was somehow laid down when atmospheric CO2 was at least twice the current elevated levels. How could this have occurred in such an “acidic” ocean environment if CO2 alarmists are right?
Furthermore, if 500 ppm is the threshold required to prevent the Pleistocene Curse of recurrent Ages, shouldn’t we be shooting for that level as a positive goal? “Cool” sounds good, so I’d be concerned if we were heading over 1000 ppm.
On a purely semantic note, Willis, my recollection from chem lab is that if you add an acid to an alkaline solution, you are “acidfying” it, even if it remains basic. So it doesn’t bother me to say that adding CO2 to the atmosphere and thence to sea water will “acidify” it.
But I do wonder, however, how low ocean pH could get even if the atmosphere were pure CO2 — carbonic acid is very weak in comparison to nitric or sulphuric, so I don’t think it would get you very far. Willie Soon claims that many alarming studies of the adverse effect of acidification on mollusk shells resort to these strong acids to achieve an unrealistically low pH. What’s the pH of club soda, anyway?
@ur momisugly CO2
If by that you the conspiracy theory that big oil is paying all the skeptics then I’ll agree it’s a sure sign made by the desperate who have no proof. Climategate is small potatoes and less than a year old in comparison to the big oil conspiracy theory. Hide your decline much?
If by that you mean the conspiracy theory that big oil is paying all the skeptics then I’ll agree it’s a sure sign made by the desperate who have no proof. Climategate is small potatoes and less than a year old in comparison to the big oil conspiracy theory. Hide your decline much?
Commenting on Dr Spencer, CO2 says:
“This man is a discredited voice and yes, I have studied all his claims.”
Your ad-hom opinion means nothing without verifiable facts. Since you are a self-described expert on Dr Spencer, please share with us the identities of all those people who have ‘discredited’ him, and state exactly why. Provide scientific facts, please, without your character-assassinating innuendo.
“The sea is a complex, buffered environment in which the pH” (and everything else) “is changing constantly.”
And yet, today, Sunday, June 20, 2010, science is truly settled. We are wallowing in a near lifeless state on the bottom of a deep cesspool, our heart rate is so faint as to be nearly undetectable. We have arrived. We are as the gods, the master of all we survey. Nothing new will ever be known again.
This interesting note on the role of bicarbonate [from wisegeek.com]
“Carbonic acid plays an important role in keeping the body’s pH stable. The normal pH of bodily fluids is around 7.4 and must be kept close to this value in order for the body to function properly. If the pH changes, whether up or down, enzymes can stop functioning, muscles and nerves can start weakening, and metabolic activities becomes impaired. The bicarbonate ion released from carbonic acid serves as a buffer that helps resist changes in pH. This means it can act as an acid or a base as the need arises.
Acids are defined as any substance that releases hydrogen ions into solutions. Bases are accepts those hydrogen ions. When excess hydrogen ions build up in the body—i.e. the fluids become more acidic—then bicarbonate ions accepts those extra hydrogen ions and keeps the body’s pH at a normal level. In the inverse, if the hydrogen ion levels drop too much—i.e. the fluids become too alkaline—then carbonic acid gives up hydrogen ions in order to keep the blood’s pH normal. This process is also seen during the transport of oxygen and carbon dioxide.
CO2 says:
June 20, 2010 at 5:42 am
How I wish that Roy Spencer is right, for the sake of the world, but how I recognise my own wishful thinking. This man is a discredited voice and yes, I have studied all his claims.
Have you ‘studied’ them as carefully as the effect of removing co2 on ocean ph, CO2?
Is this the right time for the unearthing of the Acid Rain tome?
It would seem that there are a lot of folks who have no understanding whatsoever of basic chemistry. Everybody grab their pH papers! Head for the nearest shoreline.
>> CO2 says:
Conspiracy is an assumption made by the desperate having no proof, it’s rarely proven. By its nature a conspiracy is secret. Give me an idea as to how you you imagine the thousands of scientists to conspire. Do they have a rather large meeting place? Three independent investigations have cleared the East Anglia CRU. Advise me what proof you have of a conspiracy other than repeating a conspiracy throw away. <<
First, YOU were the one who brought up 'conspiracy', so it's a straw man argument to begin with.
Secondly, it doesn't take thousands of scientists conspiring to control the direction of research, it takes only those few who control the bulk of the funding. If the funding is only going to those who agree with a hypothesis, and scientists need to bring in grant money to get tenure and continue their careers, guess which hypothesis those scientists who keep their jobs (and are thus able to publish) are going to agree with?
If you need an example, consider the Catholic Church. There are essentially no priests who disagee with the tenets of the Church. It does not require a conspiracy among the thousands of priests to maintain that, it only requires the disbelievers get weeded out early in the process. In the religion of Global Warming, the skeptics also get weeded out early.
sdcougar says:
June 20, 2010 at 7:22 am
This interesting note on the role of bicarbonate [from wisegeek.com]
“Carbonic acid plays an important role in keeping the body’s pH stable. The normal pH of bodily fluids is around 7.4 and must be kept close to this value in order for the body to function properly. If the pH changes, whether up or down, enzymes can stop functioning, muscles and nerves can start weakening, and metabolic activities becomes impaired. The bicarbonate ion released from carbonic acid serves as a buffer that helps resist changes in pH. This means it can act as an acid or a base as the need arises.
A common misconception, the carbonic acid system doesn’t act as a chemical buffer to keep blood pH around 7.4. Buffers operate to maintain the pH near their pKa, the pKa of the carbonic acid system is ~6.4, a factor of 10 out!
Now that Nina seems to be arriving and if she hangs around , I see the CO2 levels plateauing or dropping..
Remember Cold, bad, warm, good….
Check out the new Nat’l Geo for their latest AGW ! Greenland is melting! scary
story….
Hu McCulloch says:
June 20, 2010 at 6:58 am
“What’s the pH of club soda, anyway?”
The pH of water under a pure CO2 atmosphere at one atmosphere is about 4.
http://en.wikipedia.org/wiki/Carbonic_acid
The issue of ocean pH relates to the level of understanding of the buffering mechanisms in sea water.
I’ve had several discussions on various blogs with regard to buffering and “precision” of pH measurements. The question sometimes leads to a knee-jerk response of derision just for asking the question.
http://landshape.org/enm/errors-adding-up/
But there are reasonable references out there that describe what’s needed to measure pH at the levels necessary.
http://climateaudit.org/2008/09/23/sea-ice-end-of-game-analysis/?cpage=15#comment-163882
To make a long story short, there’s a reason you’re unlikely to see any graphs of long term pH trends with uncertaintly bars included.
The best reference I’ve found for measuring pH is here.
http://aslo.org/lomethods/free/2004/0126.pdf
One would have to follow my links above a bit deep to find it.
In this reference, the first full paragraph on p. 135 is an honest exposition of some remaining problems with the technique, including the possibility that there could be species in sea water that aren’t fully accounted for in the models.
“A more speculative explanation for the discrepancy could be acid-base
systems not reflected in the alkalinity calculation but perhaps present in surface waters.”
Hu McCulloch says:
June 20, 2010 at 6:58 am
But I do wonder, however, how low ocean pH could get even if the atmosphere were pure CO2 — carbonic acid is very weak in comparison to nitric or sulphuric, so I don’t think it would get you very far. Willie Soon claims that many alarming studies of the adverse effect of acidification on mollusk shells resort to these strong acids to achieve an unrealistically low pH. What’s the pH of club soda, anyway?
The pH of most carbonated drinks is around 3, Cola drinks also contain phosphoric acid. One of my students had a problem with a steel bowl that had got a little rusty due to neglect and asked my advice about cleaning it, I suggested using Coke. Much to his surprise it did a beautiful job!
Phil. says:
June 19, 2010 at 10:33 pm
flyfisher says:
June 19, 2010 at 8:53 pm
One other thing to consider: what is the standard error of their equipment? I’d be astounded if their measurement device was accurate below 0.01 pH Units.
Perhaps you should have read the paper (specifically Data and Methods):
“Measurement precision on both transects was on the order of ±0.001″
Phil,
give up now, you obviously have no knowledge of what you are demanding that everyone else accepts without question.
pH CANNOT be measured to 0.001 units. The buffer solutions used to calibrate electrodes are only accurate to +/- 0.1 pH units, and that is recognized in international standards.
If you look at the sentence you pulled from that paper, it would seem to refer to location, i.e. longitude and latitude
Verity Jones says:
June 20, 2010 at 12:21 am
“A thought – aquariums (the large public kind, not living-room sized) often have displays of tropical fish and corals. These are often in areas of colder (less alkaline) water (e.g. Seattle Aquarium). Presumably these use local seawater, filtered and heated, which may change the pH. While such large tanks are hardly natural ecosystems, corals don’t seem to ‘struggle’ in such environments. OK, perhaps they carefully control the pH and pCO2. Can anyone provide an insight?”
Some do (control the pH).
However, healthy, growing corals are regularly kept by hobbyists in marine aquaria. Aquaria are usually kept indoors, where CO2 levels are often many times higher than in the atmosphere.
To successfully keep stony corals in an aquarium you must somehow add Ca and HCO2 ions to make up for those deposited by the corals. One of the most common ways to do that is to dissolve lime stone using CO2 in a special reactor. Such aquariums tend to have considerably lower pH than natural sea water, but very healthy corals.
One of the older methods (Jaubert method) of adding Ca and HCO3 in hobby aquariums involve enhancing the natural pH variations, with low pH during the night. Presumably lime stone is dissolved in isolated pockets of water and diffuse into the aquarium.
In both cases, stony corals thrive under much lower pH conditions than we will ever see as a result of “ocean acidification”.
(A third common method of stony coral keeping involves dripping dissolved Ca(OH)2 into the aquarium. Aquaria kept using this method will have higher pH conditions than natural sea water – and thriving corals.)
tallbloke says:
June 20, 2010 at 5:01 am
CO2 says:
June 20, 2010 at 4:21 am
CO2 says:
June 20, 2010 at 1:50 am
“2) (And you didn’t try to address this one, presumably because you know you’ve been caught with your pants round your ankles) Co2 dissolved in water forms an acid. Yet you state that “A warmer ocean holds less CO2. Ocean’s with less CO2 become more acidic”.
——————
I should have added, “Because of other factors”, a warmer ocean…
Ocean acidity is not only a simple function of CO2 disolving in water, it involves the bio-mass from Phyto-plankton and Zooplankton down, which sequester CO2 drawing on the disolved CO2 carrying it to both the deep waters and the ocean floor. This is referred to as the solubility pump and the biological pump. This bio-mass of Phytoplankton and Zooplankton, residing close to the surface, is threatened by the warming of colder oceans, resulting in less absorbtion of CO2, increasing the disolved CO2 level, hence acidity. The whole issue is far more complex than a discussion about Ph, acidity and alkaline. While a warmer ocean may absorb less CO2, the CO2 level will still increase if the rate of sequestration drops disproportionally.
——————
1) if the ocean is not acidic to begin with (it isn’t) , then it can’t become “more acidic”, only less alkaline. It can undergo a process of acidification however, as Chris said.
—————–
This is just playing with words; what’s the difference between ‘a process of acidification’ and more acid? As for the pants, they don’t need ironing yet.
Tom_R says:
June 20, 2010 at 7:44 am
>> CO2 says:
———————-
I brought up conspiracy? I thought Lord Christopher Monckton invented that.
DirkH says:
June 20, 2010 at 6:13 am
“CO2 says:
BTW who are “the thousands of scientists ” and why do you carry that silly number around with you as if it means something? Are you that easily impressed? Where do you have that number from?
——————–
You mean like the 32000 anti global warming scientists petition, which included an Archbishop of Australia? As for scientists supporting human induced global warming, just Google it.
Ed Caryl says:
“If I’ve got this straight, points in the ocean that are acidifying must be cooling?”
The colder portions are more acidic. The bigger changes, according to the data above, are in the warmer regions of the ocean. However, there’s something I want to address about concentration change later in this post.
Phil says:
“However you’ve forgotten that the equilibrium concentration of CO2 in the surface water is also dependent on the pCO2 in the atmosphere which is being steadily increased by fossil fuel combustion.”
I didn’t forget it, but I didn’t state it as well as I should have. The absorption of CO2 into the ocean is less in warmer waters, but you’re correct in stating greater CO2 concentration will dissolve more CO2 in the water. So when I say it’s self-regulating, it’s due to the competing forces of the equilibrium of increased CO2 and the decreased dissolved CO2 in warmer water.
—–
Now that all being said, there’s been some griping and percentage of pH change. Yes, pH is a logarithmic scale. But look at the absolute concentration of H3O+ in the warmer latitutes. The pH is 8.0 at its maximum, which is 0.00000001 M, compared to that of the northern latitude, which is 0.0000000398 M. (M is molarity, or Moles of H3O+ per liter.) Changes here are amazingly small.
To give you an idea, one mL of 1.0 M HCl has a pH of 0. If I dilute that to 1 L with water, the pH becomes 3.0. If I dilute it to 1000 L, my pH is now 6. as you can see, the concentration of H3O+ is minute at those levels, and it’s even smaller at the pH range between 8 and 7.4. Calling a shift of 0.02 pH significant is laughable because the actual moles per liter change of H3O+ is so small that it falls within margins of error of the devices used to measure pH.
A correction :You didn’t have your toenails dissolved by the increased acidity?
Proteins (human body) dissolves in the alkaline pH range. The process to extract protein from various sources it is based on this fact: Protein dissolves above pH=8, and it is decomposed in its “salts” of the alkali used, forming amminoates from the aminoacids which were assembled forming the protein. What it is not commonly known is that proteins become re-assembled again, when pH lowers to 4,5-4,6.
http://www.ams.usda.gov/AMSv1.0/getfile?dDocName=STELPRDC5057645
Another precision: pH accounts for the free H+ (protons) dissolved (ionized) in a solution and OH- accounts for the free OH- (electrons) dissolved (ionized) in a solution. Think of water in clouds, arranged (polarized) in such a way to allow thoundsands of tons of water to defy gravity.
Think this post shows a relation of temperature (degree of activity) to pH.
Such an interesting array of comments.
@CO2 – You don’t need a “conspiracy”, all you need is grant funding for only one point of view.
I would venture that the temp of the water varies as you travel from Hawaii to Alaska as does the composition of plants and animals in the top 150 meters of water. Why…I bet even the depth of the water and whatever is on the bottom varies as well. Then we have varying current and oscillations, the thermohaline, etc. In fact, I wouldn’t be surprised if the salinity of the ocean didn’t vary along this transect.
Folks need to go back to college chemistry and re-learn how buffer systems work. I’ve just read some pretty lame “explanations” in support of ocean acidification (including my favorite, the pCO2 change due to anthropogenic CO2). This is a matter of scale and you can test it in a laboratory. Cook up some sea water, buffer it and place it in a chamber. You can crank the CO2 conc in the chamber all the way up to 700 ppm (without changing the ambient air pressure) and let it cook for a month and you won’t be able to measure a change in pH.
Chris says:
June 20, 2010 at 2:15 am
Chris, you are grasping at straws. As I said above, the point is that it is alarmist terminology. It leads people who think the ocean is neutral to be fearful that the ocean is turning into an acid.
This, and your long, long list of nitpicks above (yes, 7.0 is only neutral in pure water at 25°C, and in the ocean it’s about 6.9 … so what?) are generally technically correct and totally meaningless. The point is simple. The change in oceanic basicity is so small and so slow that it will not affect much of anything. In many places, including coral reefs, the ocean sees larger pH changes daily than the total change projected from changing CO2 over the next century.
There is one misconception of yours I do want to clear up, however. You say:
You speak in hushed tones about how
According to the references I’ve seen, if the atmospheric CO2 were to double instantaneously, the oceanic surface pH would go down by about 0.26, not 0.4. This is much less than a month’s pH change in the Monterey Bay seawater. But the extra CO2 in the surface would eventually mix throughout the ocean, reducing the atmospheric CO2 and increasing the surface basicity (your preferred term).