Rate May Be Ten Times Faster, According to New Data
From Lamont-Doherty Earth Observatory: Some 56 million years ago, a massive pulse of carbon dioxide into the atmosphere sent global temperatures soaring. In the oceans, carbonate sediments dissolved, some organisms went extinct and others evolved.
Scientists have long suspected that ocean acidification caused the crisis—similar to today, as manmade CO2 combines with seawater to change its chemistry. Now, for the first time, scientists have quantified the extent of surface acidification from those ancient days, and the news is not good: the oceans are on track to acidify at least as much as they did then, only at a much faster rate.
In a study published in the latest issue of Paleoceanography, the scientists estimate that ocean acidity increased by about 100 percent in a few thousand years or more, and stayed that way for the next 70,000 years. In this radically changed environment, some creatures died out while others adapted and evolved. The study is the first to use the chemical composition of fossils to reconstruct surface ocean acidity at the Paleocene-Eocene Thermal Maximum (PETM), a period of intense warming on land and throughout the oceans due to high CO2.
“This could be the closest geological analog to modern ocean acidification,” said study coauthor Bärbel Hönisch, a paleoceanographer at Columbia University’s Lamont-Doherty Earth Observatory. “As massive as it was, it still happened about 10 times more slowly than what we are doing today.”
The oceans have absorbed about a third of the carbon humans have pumped into the air since industrialization, helping to keep earth’s thermostat lower than it would be otherwise. But that uptake of carbon has come at a price. Chemical reactions caused by that excess CO2 have made seawater grow more acidic, depleting it of the carbonate ions that corals, mollusks and calcifying plankton need to build their shells and skeletons.
In the last 150 years or so, the pH of the oceans has dropped substantially, from 8.2 to 8.1–equivalent to a 25 percent increase in acidity. By the end of the century, ocean pH is projected to fall another 0.3 pH units, to 7.8. While the researchers found a comparable pH drop during the PETM–0.3 units–the shift happened over a few thousand years.
“We are dumping carbon in the atmosphere and ocean at a much higher rate today—within centuries,” said study coauthor Richard Zeebe, a paleoceanographer at the University of Hawaii. “If we continue on the emissions path we are on right now, acidification of the surface ocean will be way more dramatic than during the PETM.”
The study confirms that the acidified conditions lasted for 70,000 years or more, consistent with previous model-based estimates. “It didn’t bounce back right away,” said Timothy Bralower, a researcher at Penn State who was not involved in the study. “It took tens of thousands of years to recover.”
From seafloor sediments drilled off Japan, the researchers analyzed the shells of plankton that lived at the surface of the ocean during the PETM. Two different methods for measuring ocean chemistry at the time—the ratio of boron isotopes in their shells, and the amount of boron –arrived at similar estimates of acidification. “It’s really showing us clear evidence of a change in pH for the first time,” said Bralower.
What caused the burst of carbon at the PETM is still unclear. One popular explanation is that an overall warming trend may have sent a pulse of methane from the seafloor into the air, setting off events that released more earth-warming gases into the air and oceans. Up to half of the tiny animals that live in mud on the seafloor—benthic foraminifera—died out during the PETM, possibly along with life further up the food chain.
Other species thrived in this changed environment and new ones evolved. In the oceans, dinoflagellates extended their range from the tropics to the Arctic, while on land, hoofed animals and primates appeared for the first time. Eventually, the oceans and atmosphere recovered as elements from eroded rocks washed into the sea and neutralized the acid.
Today, signs are already emerging that some marine life may be in trouble. In a recent study led by Nina Bednaršedk at the U.S. National Oceanic and Atmospheric Administration, more than half of the tiny planktic snails, or pteropods, that she and her team studied off the coast of Washington, Oregon and California showed badly dissolved shells. Ocean acidification has been linked to the widespread death of baby oysters off Washington and Oregon since 2005, and may also pose a threat to coral reefs, which are under additional pressure from pollution and warming ocean temperatures.
“Seawater carbonate chemistry is complex but the mechanism underlying ocean acidification is very simple,” said study lead author Donald Penman, a graduate student at University of California at Santa Cruz. “We can make accurate predictions about how carbonate chemistry will respond to increasing carbon dioxide levels. The real unknown is how individual organisms will respond and how that cascades through ecosystems.”
Other authors of the study, which was funded by the U.S. National Science Foundation: Ellen Thomas, Yale University; and James Zachos, UC Santa Cruz.
@rgb: Thanks. Could you craft a concise scientific response to the claim, “acidity has increased by 25%”?
John Eggert says:
June 4, 2014 at 6:29 am
And wikipedia for a source? Really?
Yes really, you’re given an accessible source so live with it, too many on here moan when given a source that’s ‘behind a paywall’. References to the original source is given on the page so quit moaning!
Robert Brown says: June 4, 2014 at 10:58 am
“The true beauty of log scales is that multiplication maps into addition”
It’s late in the thread so…
Noah said to the animals “Go forth and multiply!”.
But the snakes said “we can’t do that, we’re adders”.
So Noah was mighty wroth. He went ashore with an axe, into the dying forest.
He returned and dumped it on the deck.
“Here, I have made you a log table. Go forth and multiply!”.
Couple of additional problems;
1) They’ve basically used “Mike’s nature trick” again. This time splicing high resolution direct sampling data onto low resolution core proxy data. They cannot say the change is unprecedented because the proxy is incapable of revealing rapid change.
2) The notion that the oceans are becoming “more acidic” belies the fact that they are basic. Owing to the fact that they rest on a bed of basalt, they will remain so. The only thing that may occur is CACO3 may precipitate at a faster rate, causing . . . more limestone.
New cause celeb; Catastrophic Anthropogenic Global Shale Deposits!!!
Note the irony of that; Anthropogenic CO2 emissions result in faster growth of sea floor sedimentary limestone deposits, resulting in better geology for the trapping of hydrocarbons, eventually leading to more recoverable oil reserves.
There’s such poetry in nature.
Bob Kutz says: June 4, 2014 at 12:55 pm
“Anthropogenic CO2 emissions result in faster growth of sea floor sedimentary limestone deposits”
On the contrary, CO2 dissolves CaCO3. When you sort out the carbonate chemistry, and get past the role of intermediates like H+, the nett reaction is:
CaCO3 + CO2 + H20 -> Ca++ +2HCO3-
Each added CO2 dissolves a molecule of CaCO3. From somewhere, sometime.
After 4 years of studying Chemistry in university I have never seen a change in pH expressed as a percent change in “acidity”. That is, until we heard from the “ocean acidification” industry. You just don’t see it anywhere else because it is meaningless.
While it is correct to say that it reflects a ~25% increase in hydronium ions, it is grossly misleading and absurd to say it is 25% more acidic. The change is barely detectable on instruments and is widely eclipsed by the natural variations in ocean pH.
Try an experiment with your friends… have them taste test 2 beverages: Brand A at a pH of 7.0 and Brand B at 7.1 and see if they can tell the difference. Then tell them Brand A is 25% more acidic than Brand B and they should not buy Brand A.
This is nothing but propaganda.
This chart indicates no change in ocean pH. And going by the total and complete failure of the alarmist clique to either model, or predict the real world, the default position must be that they are wrong this time, too.
The Phanerozoic Carbon Cycle, CO2 and O2
Bob Berner, Prof. of Geology, Yale
pg 38, 2nd para; ” . . . The idea is simply that if atmospheric CO2 rises, the concentration in the ocean also rises, and there is enhanced uptake by marine basalt weathering. In this way the process serves as a negative feedback for stabilizing atmospheric CO2 . . . . Alt and Teagle (1999) stated that 70-100% of the calcium in CaCO3 found in altered submaring basalts is derived from seawater, not from the basaltic minerals. This meant that most of the basalt is not actually being weathered but is simply providing a place for the interstitial precipitation of CA++ and HCO3- from seawater. The neutral-to-alkaline interstitial seawater environment, due to hydrolysis of the basalt (Caldeira, 1995), may serve to raise pH and induce CaCO3 precipitation.”
Now, in all fairness, Berner does say that this may have been far more important in the period before 150 Ma than it is today, but he also says; “Global warming due to elevated CO2 brings about accelerated phosphate weathering and transport of P to the sea, leading to an increase in aqueous nutrient P. This in turn leads to greater organic carbon burial and greater CO2 consumption, with the overall process producing negative feedback.” – ibid, pg 43, 2nd para.
Wanna go some more?
Sorry, should have directed the prior comment at Nick Stokes, in re. his 1:13 comment directed at me.
dbstealey says:
June 4, 2014 at 9:07 am
“suspected…” “…could be…” “CO2 ha[s] made seawater grow more acidic…”
No.
According to real world data from the Monterey Bay Aquarium’s intake pipe, located far out in the ocean, there has been no measurable change in pH.
Unfortunately your link turned out to be a blank pdf.
However I was able to find a couple of publications by that group. Their pH meter really didn’t have the accuracy to measure the longterm change in pH, anyway not the best site to do that measurement anyway given the regular intrusions of hypoxic, low pH water into that area, which resulted in large variation in pH.
Granted, this data stops several years ago, but it covers a time when CO2 was strongly ramping up.
The article also omits any mention of buffering — a major factor in any discussion of ocean pH; probably the major factor. Why no mention of buffering?
Which buffer had you in mind?
[Reply: No problem here accessing the Monterey pH record. ~mod.]
Nick Stokes says: June 4, 2014 at 2:48 am
“pH 7 is the neutral point of pure water. Marine organisms never encounter pure water, so that is irrelevant. They have evolved in a sea of pH>8.
Human blood has a pH of about 7.4. If it drops to 7.35, that is acidosis = bad news. Blood pH 7 is not compatible with life.”
Nick, the world out side of your lab beakers is quite the dynamic place. To point out the obvious, human blood is encapsulated inside an epithelial container in a healthy human, isolated from the environment outside. (As are marine organisms.) Your body can tolerate immersion in water having a wide range of pH, from sea water to fresh water, hard water to soft water, alkaline to acidic, without compromising the blood pH balance maintained inside your skin.
From Scripps:
“A group of 19 scientists from five research organizations have conducted the broadest field study of ocean acidification to date using sensors developed at Scripps Institution of Oceanography, UC San Diego.”…
…”This study is important for identifying the complexity of the ocean acidification problem around the globe. Our data show such huge variability in seawater pH both within and across marine ecosystems making global predictions of the impacts of ocean acidification a big challenge. Some ecosystems such as coral reefs experience a daily range in pH that exceeds the predicted increase in pH over the next century.”…
Read more at: http://phys.org/news/2011-12-comprehensive-key-ocean-ph-variations.html#jCp
By the way, I understand that human emissions of CO2 account for 4% of the increase in atmospheric CO2. That would be 4% of the purported 25% drop in pH.
As usual, context is important.
rgbatduke says:June 4, 2014 at 5:14 am
See above.
Nick Stokes;
(final point)
To put this in terms you are possibly more familiar with;
silicate rock weathering;
CaSiO3+2CO2+H2O→2HCO3- +Ca2+ +SiO2 which eventually becomes;
silicate weathering + carb sedimentation;
CaSiO3+CO2→CaCO3+SiO2
While these are processes which take much much longer than the simple ‘ CO2 and CaCO3 produce bicarbonate and cationic calcium’, they are the ‘end state’ of the reaction in the presence of silicates rather than the intermediary ‘temporary state’.
Since the bicarbonate is itself a buffer in water, I’m not sure you have any place left to stand in the ‘ocean acidification’ argument.
As was my original point; CO2 induced ocean acidification simply doesn’t stand up to scrutiny. The very bed in which the oceans lay deny any chance of it.
Given the immense amount of ocean pH data which is contradictory to what the authors of this study claim, I’m not sure you really want to stand with this particular bogeyman.
Nick Stokes says:June 4, 2014 at 5:10 am
” Shell CaCO3 once dissolved won’t reform.”
Calcareous shells form under the mantle of the shellfish, isolated from the open aqueous environment. The rate of deposition exceeds the rate of dissolution, resulting in growth.
Your skin is constantly exfoliating as new skin grows underneath. Has your skin worn out yet? I sincerely hope not.
These processes have been going on a long time. Enjoy your life. There is no steering wheel on this clown car.
Nick Stokes says:
June 4, 2014 at 2:48 am
pH 7 is the neutral point of pure water. Marine organisms never encounter pure water, so that is irrelevant. They have evolved in a sea of pH>8.
====
nope…..Nick there are plenty of places that have much lower pH…and plenty of times when they are exposed to rain…here’s a shot of the barrier at low tide….and yes…it can rain at low tide
http://media-1.web.britannica.com/eb-media/00/65300-004-C334446B.jpg
If you look at the Mauna Loa co2 yearly rate of increase since 1960, then it can be seen that the rate increased with every El Nino and decreased with every La Nina. In 1987/88 co2 has 2 record peaks close to 2.0 ppm, and then the rate drops in the preceding several years until 1992 when it drops to 0.43 ppm. In 1998, El Nino, co2 has it,s highest peak at 2.94 ppm. Then in the following year, La Nina, co2 drops to 0.93 ppm. Co2 output by man has risen every year, so it is more than obvious that nature is adding and subtracting co2 into the atmosphere according to it,s internal changes. This raises a very important question ” How much of the atmospheric co2 increase is driven by the oceans vs being cause by human output? Perhaps all atmospheric co2 is driven by changes in the ocean temps. How would we know if we are unable to separate how much either one contributes?
Stipulating all the alarmist measurements, if CO2 is the sole culprit, how is it that acidification began in 1750? Ist bin Elefantenland.
From Phil. on June 4, 2014 at 2:19 pm (link added back into a quoted section):
Sorry, Phil-dot, but it loaded just fine for me. Check your software.
goldminor says:
June 4, 2014 at 4:36 pm
How much of the atmospheric co2 increase is driven by the oceans vs being cause by human output?
The increase is near entirely human: the oceans and vegetation are net sinks for CO2, not sources. Human input is about twice the increase of CO2 in the atmosphere, thus nature is a sink for halve of the human input (as mass, not original molecules):
http://www.ferdinand-engelbeen.be/klimaat/klim_img/dco2_em2.jpg
The variability you see in increase rate is a variability in sink rate and mainly caused by vegetation, not by the oceans, as reaction to temperature/precipitation changes mainly in the tropical rain forests. That can be deduced from the 13C/12C ratio variations which are opposite to the CO2 rate of change variations:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_dco2_d13C_mlo.jpg
If the oceans were the cause, the 13C/12C ratio changes would be the same direction as the CO2 changes.
Richard G says:
June 4, 2014 at 2:32 pm
By the way, I understand that human emissions of CO2 account for 4% of the increase in atmospheric CO2. That would be 4% of the purported 25% drop in pH.
Bad argument… human emissions are 4% of the total emissions, but 0% of the total sinks, thus 100% of the increase (in fact a little less, the increase in temperature also has a small contribution). The natural emissions are an estimated 150 GtC/year, the natural sinks are some 4.5 GtC higher. Human emissions are around 9 GtC/year.
Yet another paper which cannot distinguish between sea water and surface sea water!
Why is that distinction important? Because the statement
“In the last 150 years or so, the pH of the oceans has dropped substantially, from 8.2 to 8.1”
is clearly wrong!
http://wattsupwiththat.com/2010/06/19/the-electric-oceanic-acid-test/
This pH change of sea water takes only place in about 1% of the sea water!
=> It speaks loudly of the professional level of the reviewers to let such a plunder pass repeatedly over the last decades.
Any time some one is talking about the sea is a net sink for CO2, ask them how the amount (about 200GtC) compares to the accuracy which which we know the total amount of CO2 in the oceans (about 1% of 38000GtC).
I claim that we dont know enough about the CO2-circuit to make such statements.
Laws of Nature says:
June 5, 2014 at 1:23 am
The distribution of CO2 between the ocean “mixed layer”, that is the upper 100-300 meters of the oceans is quite rapid (half life ~1 year) and the carbon content is comparable to the atmosphere (~1000 GtC mixed layer, ~800 GtC atmosphere). The distribution between atmosphere / mixed layer and the deep oceans is a lot slower (~50 years half life time), thus it takes time to get a new equilibrium, which indeed is at 1% rise of CO2 in the atmosphere and total ocean carbon content. But that also gives that the mixed layer pH is following the atmospheric CO2 content. In the mixed layer most of the ocean biolife is at work…
One doesn’t need to measure the increase in the deep oceans, a simple mass balance gives you the answer: sinks in the biosphere are known from the oxygen balance, in the ocean surface layer are a matter of buffer capacity (about 10% change for a 100% change in the atmosphere) and the rest is in the deep oceans.
Nick Stokes:
Thankyou for the clarification you provide to me at June 4, 2014 at 12:12 pm where you reply to my having asked
By saying
OK. I get that. You are saying
1.
Nobody knows the “cause of PETM etc warming” but it is not CO2.
2.
Atmospheric CO2 has no natural variability and only changes because “something has to be forcing CO2 into the atmosphere”.
3.
We are forcing CO2 into the atmosphere because otherwise “there is mostly nothing obvious to do that”.
Thankyou for your clarification of your assertions. But I like scientific assessments and I prefer them to superstitious assertions of the kind you have provided.
Richard
Ferdinand Engelbeen:
I have no intention of yet again repeating our arguments on WUWT. I write to explain to any who may not know that for many years you, I and Bart have been arguing the cause of the recent rise in atmospheric CO2 concentration.
Bart claims the rise has an entirely natural cause, you claim the rise has an entirely anthropogenic (i.e. human-induced) cause, and I don’t know if the rise has a natural cause, or an anthropogenic cause, or some combination of natural and anthropogenic causes.
Your post in this thread at June 4, 2014 at 11:35 pm says
Your reply is plain wrong.
At issue is what the increase in atmospheric CO2 would have been if there were no anthropogenic emission. Your answer assumes the anthropogenic emission is the total cause of the rise because the sinks cannot sequester all of the total emission.
Your assumption is not true.
I have repeatedly explained to you that the dynamics of the seasonal cycle demonstrate your assumption is plain wrong.
This is the CO2 data from Mauna Loa
http://www.esrl.noaa.gov/gmd/ccgg/trends/
The seasonal variation in each year is a slow rise indicating increase to atmospheric CO2 that is followed by a steep fall as sequestration of CO2 is greater than CO2 emission which is followed by a rapid reversal. There is no reduction to the rate of sequestration as the sequestering ‘sinks’ fill. Clearly, the sinks do not fill.
The annual rise of any year is the residual of the seasonal variation of that year.
The dynamics of the seasonal change is consistent with the carbon cycle adjusting to a new equilibrium:
(a) adjustment of mechanisms with long rate constants provides the annual rise
while
(b) adjustment of the mechanisms with very short rate constants provides the seasonal variation.
The recent rise in atmospheric CO2 concentration is consistent with adjustment of the carbon cycle to a new equilibrium but is NOT consistent with the CO2 sinks lacking ability to sequester all the CO2 emissions. The anthropogenic CO2 emission may be the cause of a changed carbon cycle equilibrium but other causes are more likely.
Richard
“Nobody knows the “cause of PETM etc warming” but it is not CO2.”
I said very clearly that I do not know. I did not say nobody knows, nor that it is not CO2. You made that up.
“Atmospheric CO2 has no natural variability and only changes because “something has to be forcing CO2 into the atmosphere”.”
I said nothing of the sort. I said that if you want to say CO2 rise is forcing temperature rise, you have to ask what is forcing CO2 rise. Of course CO2 has natural variability. It responds to temperature and bio activity. It has a seasonal cycle.
“We are forcing CO2 into the atmosphere because otherwise “there is mostly nothing obvious to do that”.”
We are forcing CO2 rise in emitting about 30 Gt/year. This stuff isn’t difficult. Well, maybe it is if you don’t believe we’re emitting CO2.