WOODS HOLE OCEANOGRAPHIC INSTITUTION
Scientists have long suspected that ocean acidification is affecting corals’ ability to build their skeletons, but it has been challenging to isolate its effect from that of simultaneous warming ocean temperatures, which also influence coral growth. New research from the Woods Hole Oceanographic Institution (WHOI) reveals the distinct impact that ocean acidification is having on coral growth on some of the world’s iconic reefs.
In a paper published Aug. 27, 2020, in the journal Geophysical Research Letters, researchers show a significant reduction in the density of coral skeleton along much of the Great Barrier Reef–the world’s largest coral reef system–and also on two reefs in the South China Sea, which they attribute largely to the increasing acidity of the waters surrounding these reefs since 1950.
“This is the first unambiguous detection and attribution of ocean acidification’s impact on coral growth,” says lead author and WHOI scientist Weifu Guo. “Our study presents strong evidence that 20th century ocean acidification, exacerbated by reef biogeochemical processes, had measurable effects on the growth of a keystone reef-building coral species across the Great Barrier Reef and in the South China Sea. These effects will likely accelerate as ocean acidification progresses over the next several decades.”
Roughly a third of global carbon dioxide emissions are absorbed by the ocean, causing an average 0.1 unit decline in seawater pH since the pre-industrial era. This phenomenon, known as ocean acidification, has led to a 20 percent decrease in the concentration of carbonate ions in seawater. Animals that rely on calcium carbonate to create their skeletons, such as corals, are at risk as ocean pH continues to decline. Ocean acidification targets the density of the skeleton, silently whittling away at the coral’s strength, much like osteoporosis weakens bones in humans.
“The corals aren’t able to tell us what they’re feeling, but we can see it in their skeletons,” said Anne Cohen, a WHOI scientist and co-author of the study. “The problem is that corals really need the strength they get from their density, because that’s what keeps reefs from breaking apart. The compounding effects of temperature, local stressors, and now ocean acidification will be devastating for many reefs.”
In their investigation, Guo and his co-authors examined published data collected from the skeletons of Porites corals–a long-living, dome-shaped species found across the Indo-Pacific– combined with new three-dimensional CT scan images of Porites from reefs in the central Pacific Ocean. Using these skeletal archives, which date back to 1871, 1901, and 1978, respectively, the researchers established the corals’ annual growth and density. They plugged this information, as well as historical temperature and seawater chemistry data from each reef, into a model to predict the corals’ response to constant and changing environmental conditions.
The authors found that ocean acidification caused a significant decline in Porites skeletal density in the Great Barrier Reef (13 percent) and the South China Sea (7 percent), starting around 1950. Conversely, they found no impact of ocean acidification on the same types of corals in the Phoenix Islands and central Pacific, where the protected reefs are not as impacted by pollution, overfishing, runoff from land.
While carbon dioxide emissions are the largest driver of ocean acidification on a global scale, the authors point out that sewage and runoff from land can exacerbate the effect, causing even further reductions of seawater pH on nearby reefs. The authors attribute the declining skeletal density of corals on the Great Barrier Reef and South China Sea to the combined effects of ocean acidification and runoff. Conversely, reefs in marine protected areas of the central Pacific have so far been shielded from these impacts.
“This method really opens a new way to determine the impact of ocean acidification on reefs around the world,” said Guo. “Then we can focus on the reef systems where we can potentially mitigate the local impacts and protect the reef.”
Co-authors of the paper include Rohit Bokade (Northeastern University), Nathaniel Mollica (MIT-WHOI joint program), and Muriel Leung (University of Pennsylvania), as well as Russell Brainard of King Abdullah University of Science and Technology and formerly at the Coral Reef Ecosystem Division of the Pacific Islands Fisheries Science Center.
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Funding for this research was provided by the National Science Foundation, the Tiffany & Co. Foundation, the Robertson Foundation, the Atlantic Donor Advised Fund, and WHOI’s Investment in Science Fund.
The Woods Hole Oceanographic Institution is a private, non-profit organization on Cape Cod, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the ocean and its interaction with the Earth as a whole, and to communicate a basic understanding of the ocean’s role in the changing global environment. For more information, please visit http://www.whoi.edu.
Key Takeaways
An innovative numerical model developed by researchers at the Woods Hole Oceanographic Institution demonstrates the distinct impact of ocean acidification–separate from ocean warming–on coral growth.
The model shows that ocean acidification has caused a 13 percent decline in the skeletal density of Porites corals in the Great Barrier Reef, and a 7 percent decline in the South China Sea since 1950.
Pollution and land runoff can exacerbate the effects of ocean acidification, causing corals in local reefs to weaken more quickly than those located farther away from human settlements.
A global-scale investigation of coral CT scans could help to target protections for vulnerable reefs.
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“New research from the Woods Hole Oceanographic Institution (WHOI) reveals the distinct impact that ocean acidification is having on coral growth”
Maybe so but how was it determined that the co2 that did it came from fossil fuel emissions?
https://tambonthongchai.com/2020/08/14/ocean-volcanism/
See also
https://tambonthongchai.com/2020/08/22/ocean-acidification/
The article as published here seems to indicate the decrease in density was a modeled output, based on a theoretical starting value from before there was any way to measure ocean pH.. Were there any actual measurements of before/after that show the claimed results?
From what I’ve read, the decrease in pH is only a modeled number. Actual measurements have detected pH changes (aside from season differences, algal bloom conditions, and other temporary variations) have only been found in a few very local situations. Is this not true?
Like global warming, ocean acidification is “worldwide”, but only occurs where human activity is most active (urban heat islands). Acidification impact to coral is not occurring in protected areas without pollution, land runoff, island construction (is not exacerbating acidification). Interpretation is in the eye of the believer.
MR. Quarles: I saw that, too. My analogy would be to the man found dead in his closed garage with car motor running. These folks say he died of increased air acidification from co2. The neighbor who left his motor running with garage door open was ok. They would explain this as, the air acidification was intensified by carbon monoxide in the case of the dead guy.
Carbonate ions down 20% when ph goes from 8.2 to 8.1? Measured? I could be wrong, but that doesn’t compute.
The “thinning skeleton” is the decaying structure underlying AGW theory.
Would like to see what Peter Ridd has to say about this!
Exactly. Also, you know it’s a scam when they resort to “acidification”.
nice overseas jolly for 4 or more people to take core samples from coral
I seem to remember that fast growing trees and plants generally don’t have the same density as slow growing ones, the key words are `fast` and `growing`
I agree this is a plea for more tax-funded “working vacation” trips to lovely, exotic ports of call.
Isn’t it interesting that whenever someone states “Increased atmospheric CO2 CAUSED acidification” of ocean waters, they seem to fail to show any contemporaneous MEASUREMENTS of marine pH. Hmmmm – no data, just attribution
The oceanographic research I have read that actually reports measurements of marine pH shows wide variation on daily, seasonal, and annual timescales. So what is the value of “averaged pH” when the coral is responding to very local, highly variable conditions?
This work is flawed by bias from the start
No more SCUBA trips for you, young lady. Time to go back to the library and study chemistry and oceanography.
OK, someone has to say it, so I might as well be the one to point out that “ocean acidification” is actually “ocean declining alkalinity.” The ocean is not turning to acid, and never will under current or anticipated conditions. But it’s alkalinity of 8.2 has declined to about 8.1 since the beginning of industrialization, or so it is claimed. If you want to call that “acidification” – and anyone who wants to be published has to call it that – have at it. No need to cling to the niceties of science when a juicy grant is on the line.
“No need to cling to the niceties of science when a juicy grant is on the line.”
A juicy grant IS the ‘niceties of science’ nowadays. Ask any climate researcher why they are doing their job. They will NOT say “to discover the truth about natural processes”. Most likely they will say “to make the world a better place” – where ‘a better place’ involves getting the Democrats elected in the US, and pro rata for any European country….
Let’s just ignore the carbonate sand and mud that comprises the seafloor of every carbonate platform around the world’s oceans.
Edward
The Usual Suspects (aka researchers) have rejected the historical measurements and used a model to extrapolate backwards in time the average pre-industrial pH.
I am sick and tired continuously freshly minted alarmist claims that turn out to be “not quite so, but…” – and the research to produce them paid by public money!
I guess I’m on the wrong side: I too would like to have a paid vacation on Palau to drill into corals or whatever.
MY ‘Key Takeaways’ …
An innovative numerical MODEL… (what brand & colour of Plasticine did they use ???)
demonstrates the distinct impact of ocean ACIDIFICATION … (when did the ocean move from alkaline to fresh pH7 to acid ???)
“Disclaimer: AAAS and EurekAlert! are NOT RESPONSIBLE FOR THE ACCURACY of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.”
And there was me thinking that settled science says coral, chalk & limestone was caused by CO2 in ocean !! water
“The authors attribute the declining skeletal density of corals on the Great Barrier Reef and South China Sea to the combined effects of ocean acidification and runoff. Conversely, reefs in marine protected areas of the central Pacific have so far been shielded from these impacts.”
So where there’s no run-off, there’s no problem. But where there is run-off, the problem is due to ocean acidification as well.
So the solution to the effects of ocean acidification is simply to stop run-off apparently.
Any other global problems you’d like me to solve while I’m here?
Also may I have a free trip to Pulau please?
Two causes are not separately quantified. When one of the causes is absent, and the effect disappears entirely, we have problem in basic logic. Or is the extra CO2 not present in the air over some remote islands?
“They plugged this information, as well as historical temperature and seawater chemistry data from each reef, into a model to predict the corals’ response to constant and changing environmental conditions.”
A model?
No “scientist” says a declining ph number, still in the alkaline range, is acidification. Measuring a decrease in density of corals almost certainly actually means that their growth-rate has accelerated and they are getting bigger/faster. This is political science from one of the usual suspects.
Ron Long wrote: “Measuring a decrease in density of corals almost certainly actually means that their growth-rate has accelerated and they are getting bigger/faster.”
This was exactly my thought as well. Decreasing density means that the corals are growing at a faster rate. This is usually a sign of good health, more nutrition, or something like that. And the added nutrition is probably far more likely to be from runoff than from CO2 dissolved in the water from the air, in any case. And besides, isn’t the water, if it’s warmed by CO2, then going to give OFF more of it’s already dissolved CO2 to the air? Where do we see this measurement?
This faux scare appears to be not unlike the argument that alarmists make about crop foods, which are growing faster because of CO2 fertilization, having less nutritional value per unit of measure because they’re growing so fast. As an economic argument it fails even most basic sniff test, as some real commercial greenhouses, at that own expense, pump in CO2 artificially, in order to enhance plant growth. But the tendentious alarm mongers care not one whit that the extra CO2 makes much, much more overall nutrition, only in desperately finding a measure that they can interpret as a negative to advance their narrative. Ergo now we must be worried by slightly less nutrition per unit of measure. Of course, we might also decide that this extra volume is roughage, which is good for the digestion, good for the colon. We could say that, if we wanted to, could we not? Thus, we could report that the extra growth is not just good, but doubly good (Or doubleplusgood, since they are totalitarians at heart, should we not associate climate scare stories with Orwellian terminology).
I’d bet $100 that the divers drilling the cores from these corals , with their suntan lotions, their oily hands, their coring drill bits, are impacting this coral far more than is atmospheric or dissolved CO2. Runoff of agricultural chemicals and fertilizers IS a legitimate concern, which should be understood and mitigated, where possible and practical. But how can you understand a topic when you tendentiously and falsely ask the wrong questions of the natural world?
I suspect they are looking at problems from land run-off, not a tiny 130 ppm CO2 increase.
They should try 95,000 ppm of CO2 in seawater from volcanic vents, acidifying it to a pH of ~ 6.0 and still the coral thrives:
https://notrickszone.com/2020/03/30/new-study-coral-reefs-thrive-near-acidic-waters-ph-6-0-where-seafloor-vents-emit-up-to-95000-ppm-co2/
Excellent comment! What the hell is a “spangled drongo”?
A bird and Australian slang mild insult…
Perfect reference – thanks.
Wow! This acidification thing MUST be real! I keep reading about it on the internet, so yeah…
Ocean “acidification” is a confected non issue.
According to the last Australian State of the Climate Report, “ acidification” in the Oceans around the Australian continent has seen Ph reduce over the last century from 8.18 to 8.08.
The IPCC figure notes a decline worldwide in Ph from ~8.2 to ~ 8.1 since pre- industrial times.
The world oceans have been alkaline since the late Precambrian, about 750 million years ago when the amount of CO2 in the atmosphere was up to 20 times higher than now.( Kump et al 2000).
Since the Precambrian, CO2 has been progressively removed from the atmosphere via inorganic and organic carbonate sediment deposition mostly in marine environments.
These geological, geochemical and biological processes continue today in an ocean that is heavily buffered by water rock and water sediment reactions.
In effect it is difficult to permanently change the ocean Ph by adding acids (including the mildly acidic H2CO3) or bases because any increase or decrease in the number of hydrogen ions is first compensated for by reactions with other minerals present, for example clay minerals.
Although the boron isotope analysis is controversial, as long ago as the middle Eocene, some 45 million years ago, the Ph range in shallow water is estimated to have been similar to today, at 8.33 to 7.91.( Holland H.D. “The Chemical Evolution of the Atmosphere and Oceans” 1984.)
I am indebted to the late Professor Robert Carter for this summary.
It’s pH, not Ph.
That’s your take away? Pedantic much? 😉
Where’s Griff when you need him?
Thanks for correction.
Senior’s moment.
And the pH scale was only invented in 1909 and the current definition of it in 1924, so there are NO measurements to prove that it has declined fom pre-industrial times.
It’s “models all the way down”.
Incidentally the CCD, the depth where carbonates start to dissolve in the oceans is 4200 to 5000 meters. The weird thing is that there are actually corals that live below the CCD, though they are not hermatypic, i. e. they don’t form reefs.
“WHOI SCIENTIST ANNE COHEN (LEFT) AND MIT-WHOI JOINT PROGRAM STUDENT NATHAN MOLLICA EXTRACT CORE SAMPLES FROM A GIANT PORITES CORAL IN RISONG BAY, PALAU.”
Maybe they should first take core samples of themselves to see how well the process works.
(Just venting with a smile.)
Stay safe and healthy, everybody.
Bob
“they should first take core samples of themselves”
We advance a hypothesis of brain calcification. Some others have proposed a sedimentation process.
After all, it has often been observed that “That person must have rocks in their head.” Obviously true, however the rocks have to get there somehow.
I agree, core samples would distinguish between the two proposed processes of cranial rock formation.
Theory Guides, Experiment Decides.
They really are science illiterate, so vent warranted. The stupid in this one is so bad that it hurts. It’s like they passed chem 101 with a C- and never even heard of carbonate sedimentology.
Robert
No, they are just following the advice in the Writer’s Guide to Successful Grant Applications. That is, use the key words that the grant reviewers are looking for to be sure that you are card carrying members of the alarmist guild. Others need not apply.
“The authors found that ocean acidification caused a significant decline in Porites skeletal density in the Great Barrier Reef (13 percent) and the South China Sea (7 percent), starting around 1950. Conversely, they found no impact of ocean acidification on the same types of corals in the Phoenix Islands and central Pacific, where the protected reefs are not as impacted by pollution, overfishing, runoff from land.”
So ocean “acidification” (sic) only occurs where there is overfishing, pollution, or runoff. Carbon dioxide is such a clever molecule, and knows where to dissolve in coral reefs.
1. There is no such thing as ocean “acidification”. The concepts reflect a lower than moderate knowledge of chemistry.
2. Averages of pH are used.
!!!!!!!!
Do the authors know what is pH? Have they the slightest idea of what is an average of logarithms?
“Averages of pH are used.”
My thought exactly, JMS. I’ve had more than one industrial problem where I have had to convert pHs to [H+] to do a real average. Also, the averages for the whole ocean are not germane, pHs are local and vary with weather, currents, biological activity and time of day. Failure to account for these factors makes the conclusions suspect.
“a 13 percent decline in the skeletal density of Porites corals in the Great Barrier Reef… since 1950”
That can’t be good.
Baseless assumption are your thing, aren’t they Loy… DOH !!!
When the facts don’t support your case, pound the table.
Yep, that is the alarmist way for sure
Always pounding the table.
Young coral gets denser with age.. just like you will !
It could mean they are growing faster without being eaten by those overfished fish, in the warmer sea with more plant food. I ran aquariums at a relatively well known university for 5 years, and we bubbled in CO2 to help the algae grow to feed the fish.
So it could indeed be good.
Loydo said: ““a 13 percent decline in the skeletal density of Porites corals in the Great Barrier Reef… since 1950”
That can’t be good.
Not knowing if skeletal density in Porites varies naturally for example with age, depth of water or natural changes in water temperature, or their placement from the inshore to shelf-edge reef, or maybe some other unknown factor I couldn’t say if it was good or bad.
……. but your quote was missing some rather important information don’t you think?
“The authors found that ocean acidification caused a significant decline in Porites skeletal density in the Great Barrier Reef (13 percent) and the South China Sea (7 percent), starting around 1950. CONVERSELY, they found no impact of ocean acidification on the same types of corals in the Phoenix Islands and central Pacific, where the protected reefs are not as impacted by pollution, overfishing, runoff from land.”
Seems their OA hypothesis only works where there is pollution, overfishing, and runoff from land.
It also can’t be caused by CO2.
Since it is only happening in places with heavy run-off. No run-off, no decline in skeletal density.
If you actually care to become somewhat literate in the subject, here is a short and easy read.
https://www.academia.edu/43859654/Algorithms_in_Ocean_Chemistry
One key takeaway: “In any case, CO2 removed from the atmosphere will eventually form limestone.”
It makes sense that CO2 fertilization should causes the coral to grow quicker, thus reducing overall “density” they measure with their core samples…If one believes there is a general pH change against the rather large background noise.
Loydo
I presume that you are assuming that a decline of any type is bad. If you had a Body Mass Index of 30 and went on an exercise program and reduced your BMI to 25, would you consider that bad? The other possibilities are that 1) a reduction of skeletal density is of no consequence, or that 2) there are survival advantages for a reduced density in warming waters. I suggest that you make a case for one of the three possibilities, rather than flippantly just assuming that any reduction is bad.
I put some citric unalkaline in my kettle yesterday*.
The coral formations rapidly disappeared.
Have I got the hang of this Kemistry thing and can I have a grant for it?
*Should that now read penultomorrow?
Is this an attempt at a joke or is the joke in the header?
“causing an average 0.1 unit decline in seawater pH since the pre-industrial era.”
Utter BS.. they can’t measure ocean pH to that accuracy now,
and they certainly couldn’t pre-industrial age.
No different than claiming knowledge of temperatures to the 1/100th in 1850 simply by doing averages!
It sounds like university chemistry and biology labs have forgone any education in measurement uncertainty and significant digits. Probably more important to get answers from experiments that FEEL correct!
just use a model…. then they can get the answer to 5 or 6 decimal places . 😉
For some reason I pronounced the acronym WHOI as hooey.
Woods Hole has also been recently aligned with some people and organizations that want to end forestry. They have no clue. One of the honchos at Woods Hole is Bill Moomaw, a former enviro professor at Tufts. He detests all tree cutting and thinks if we end tree cutting- it’ll help save the Earth. Of course he lives in a HUGE wooden home in elite Williamstown, MA- the home of ultra elite Williams College.
Once again scientists miss the real action by neglecting the solar influence.
Solar irradiance affects coral reef growth positively via warming waters up to the bleaching threshold of about 30C, and negatively afterwards during Marine Heat Waves, when CO2 gets dissolved from coral skeletons enhancing local pCO2, then outgassed, adding to ML CO2.
– from my 2020 LASP Sun-Climate Symposium poster contribution.
Did Watts do the pumice raft article? Mother Nature creates gigantic rafts of pumice which replenish reefs.
strange how it is missing out the areas where the coral is in pristine condition- where man does not go or where pesticides aren’t used.
Woods Hole, Racial Carson worked there. Look at how she started the Green movement and caused the death of millions by pushing for the ban on DDT.
VK5ELL MJE