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.
This cannot be : a recycle of all the previous catastrophic ocean acidification “garbage” fear mongering studies. Simply shuffle the positions of words such as “could”, “perhaps”, “possibly”, and, of course, “estimate”. The watermelons just keep recycling this trash, and the left of liberal media spoon feed it to the 47 percent too dumb, but allowed to vote anyway.
As I have posted before, this will never end, I see nothing but very bad, ahead.
You mean all the sea organisms today are the ones which survived the last event and are therefore capable of accepting similar levels?
You mean we wouldn’t be here at all if the last event had not happened?
” the pH of the oceans has dropped substantially, from 8.2 to 8.1–equivalent to a 25 percent increase in acidity”
Really???
“she and her team studied off the coast of Washington, Oregon and California showed badly dissolved shells.”
Probably right around spreading centers where a lot of acidic water is being pumped into the ocean.
A pH of 7.8… Uh, that’s still alkaline. Not acid until it goes below 7.0.
Where’s the news here?
“have made seawater grow more acidic”
Utter BS..
The seas ARE NOT acid and they WILL NEVER be acid.
Since they are not acidic, they cannot become more acidic.
They may have become a tiny bit LESS BASIC or LESS CAUSTIC
,
but that is not the same thing, and may I fact be a GOOD THING…..
just like everything else to do with increasing atmospheric CO2.
And I would love to see how they measured the PH of sea water to the nearest 0.1 , 150 years ago. !!
Just like in the recent past, the warming in the PECM preceded the increase in CO2 levels.
As usual, alarmists don’t like facts getting in the way of their theories.
http://adsabs.harvard.edu/abs/2007Natur.450.1218S
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.
Better check the promulgation and evolution of The Message.
http://ocean.nationalgeographic.com/ocean/critical-issues-ocean-acidification/
(no date, apparently dynamic page, subject to change)
So drop about fifty years from the dramatic rise of Ocean Neutralization for a more worrisome rate.
But the new work says the pH drop by 2100 has been drastically cut, down to 0.3 pH from 0.5.
There is hope! Human impact will not be as bad as was thought!
From 2008, article, shouldn’t change:
http://www.scientificamerican.com/article/rising-acidity-in-the-ocean/
So what they used to say we filthy humans did in 50 to 80 years, we perversions of the natural order now did in 150 to 200 years, we took three times longer.
The “facts” are getting less alarming, humans aren’t as badly the horrendous destroyers of innocent planets we used to be.
Things are really looking up!
Oh my God noooooo….It’s even worserer than we thought.
From A Basic History of Acid—From Aristotle to Arnold:
There is no global database of pH variability in the oceans. Dore et al. (2009) uses data from station ALOHA to document a “decreasing trend” of pH, “which is indistinguishable from the rate of acidification expected (emph. added) from equilibration with the atmosphere.”
From:
Dore et al. (2009) Physical and biogeochemical modulation of ocean acidification in the central North Pacific. PNAS July 28, 2009 vol. 106 no. 30:12235–12240
From (Reference 9 in quote above):
9. Takahashi T, et al. (2009) Climatological mean and decadal change in surface ocean
pCO2, and net sea-air CO2 flux over the global oceans. Deep-Sea Res II 56:554–577.
Seriously. Can someone explain to me how the warming oceans take up this carbon dioxide whilst at the same time giving it off??
http://www.newscientist.com/article/dn20413-warmer-oceans-release-co2-faster-than-thought.html#.U47SPdq9KSM
pH is a logarithmic scale, so to say that it is 25% more acidic because it has moved by 0.1 pH units is utter bs. It would be 25% more acidic if it moved by 3.5 pH units. True, there are 25% more hydrogen ions, but there are 25% more hydrogen ions for any 0.1 movement in pH. If we used another set of pHs for example, that water at a pH of 7.0 (that is, completely neutral) is 25% more acidic than water at pH 7.1 (barely alkaline) shows you the meaninglessness of their statement.
The benthic extinction at the PETM is a bit more complex than this study suggests. There was another step in the process of generating the CO2 which is overlooked. The most popular theory of the origin of the CO2 was a massive dissociation of methane hydrate on the continental shelves and perhaps deeper environments. The resultant methane would have quite rapidly (geologically) degraded into CO2. That was not the killer. When one liter of methane hydrate dissociates on the seabed, it produces 160 liters of methane and 800ml of pure water. Note that – pure water – not salt water. The result would have been a fresh water, or at least brackish water horizon at the seabed sediment/ seawater interface. This would have killed or severely depleted benthic faunas. The evidence of this can be seen in some areas where Paleocene/Eocene boundary sediments have manganese layers in sediments interpreted to have been deposited in relatively shallow waters – not the deep waters where manganese nodules are well known to be deposited. Manganese will only precipitate out of sea water in the presence of freshwater. The manganese rich layer at the P/E boundary across the North Sea, for instance, could not have been deposited due to fluvial influences around the basin as it is so widespread. It had to have been a synchronous major event such as a methane dissociation event.
A secondary effect of the release of methane into the oceans at that time would have been a reduction of buoyancy for marine planktic species from whales to foraminifera. The partial extinction of planktic foraminiferal species during the same event may be related to this as some species were more able to cope with the reduction in buoyancy due to their shape than others.
To say that CO2 was the killer is to simplify the extinction event and to focus the attention on a fashionable possibility.
It may be worth saying that the greenhouse earth that developed after this event was responsible for massive greening of the Eocene world which allowed the development of a variety of mammalian species and the rapid evolution of primates.
Any article that claims a pH of 8.1 is acidic is pure BS and it, together with the researchers, should be binned and banned.
Ocean pH has not been measured for long enough yet to make any assumptions about pH cycles. It has been known for years, longer than the CAGW crap, that ocean pH varies round the planet from 8.4 to 7.6 in surface waters. Waters surrounding thermal vents is acidic at pH4,5 or less.
This claim is total crap produced by morons.
‘From seafloor sediments drilled off Japan’. There is, off course, no tectonic activity there.
Timothy Bralower, a researcher at Penn State who was not involved in the study. “It took tens of thousands of years to recover.
I guess I can make a legitimate comment too. After all, I wasn’t involved in the study either.
My comment is ‘ Utter BS’
So, what was the pH of the ocean during the geological epochs when atmospheric CO2 levels were over 1500 ppm?
What is the error in the measurement of pH levels?
IMHO, there isn’t enough data to reliably calculate the average pH of today’s oceans, let alone the average pH 150 years ago.
Usually I don’t agree with with those who simply dismiss papers as ”garbage” but in this case I tend to agree.
“Some 56 million years ago, a massive pulse of carbon dioxide into the atmosphere sent global temperatures soaring.”
Actually the best profiles show the normal pattern – warming (and the biotic changes it caused) came first, the carbon isotope changes followed slightly later.
“In the last 150 years or so, the pH of the oceans has dropped substantially, from 8.2 to 8.1”
The pH scale wasn’t even invented until 1909, and consistently measuring pH differences of 0,1 units in the laboratory is challenging even today, so how do they know?
“ocean acidity increased by about 100 percent in a few thousand years”
And exactly what does 100% mean on a logarithmic scale?
“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.”
One of the most embarrassing things with the PETM is that despite the very large and sudden warming practically no extinctions resulted. About the only exception is the benthic foraminifera (which by the way are very far from the only animals “that live in mud on the seafloor”). That extinction is usually ascribed to the fact that the temperature of the deep seas increased by about 10 degrees (centigrade) in just a few thousand years. There is no sign of any extinctions “further up the food chain”, nor in surface waters where this “terrible acidification” occurred.
To the contrary during the PETM life both on land and in the oceans flourished and dispersed as never since. The ancestors of a very large proportion of the animals alive today (including us) first show up during the PETM.
“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”
It should be pointed out that the “acidification” in this case is due to increased upwelling of deep water in the coastal areas. Deep ocean water contains less oxygen and more CO2 than surface water. Deep ocean water has a turnover time of c. 1000 years before it returns to the surface. During these 1000 years deep ocean life consumes a lot of the oxygen and turns it into CO2. Upwelling waters incidentally are also very rich in nutrients, so the fisheries on the West Coast are very dependent on these periodic upwellings, though it can be bad for oyster larvae. So – no this “acidification” has little or nothing to do with the modern increase of atmospheric CO2. Must be due to all those medieval SUV:s which caused the MWP.
From 2012, a WUWT repost of a great Jo Nova piece examining a new Scripps paper:
Many additional “acidification” links at Jo Nova, the WUWT version includes the full Matt Ridley piece. Both have informative graphs. Enjoy.
For those who are wondering:
pH=8.2 gives a H concentration of 6.3095E-9
pH=8.1 gives a H concentration of 7.9432E-9
7.9432-6.3095=1.6337
(1.6337 · 100)/6.3096 = 25.89%
So, let me see if I have this straight: human related emissions are adding CO2 to the atmosphere, resulting in warming. (Apparently Mosher says CO2 is a “control knob”, right?).
Warming causes the oceans to warm; when they do, they outgas CO2, correct?
How then do the oceans manage to absorb more CO2, resulting in a lowering of pH? (doesn’t matter whether anyone calls it acidifying, or being less alkaline: that’s what it comes down to).
Are the oceans capable of absorbing more CO2 than they outgas as they warm, because of higher concentrations in the atmosphere? Has anyone proven this using experiments?
This is a bit bizarre. Ocean ‘acidification’ is if anything causing the ocean to become less alkaline based on those pH values – as others have commented. But we have to assume surely that the authors of this work also know this. So what would they say is the reason why the ocean becoming more neutral is bad for shellfish? I’d they were here defending their work I mean? We can’t just assume they don’t know basic chemistry surely?
Caustic comment about acidic sea.
Fish swim and pee in the sea.
Bull Mer’d comes from land.
Thankyou Urederra- the first intelligent comment on this thread.