Guest Post by David Middleton
Introduction
As global warming morphs into climate change and global climate disruption and anthropogenic CO2 emissions give way to stochastic variability, clouds, the Sun, cosmic rays and our oceans as the primary drivers of climate change, environmental extremists are raising a new CO2-driven ecological disaster scenario to hysterical levels: Ocean acidification. Claims have been made that oceanic pH levels have declined from ~8.2 to ~8.1 since the mid-1700’s. This pH decline (acidification) has been attributed to anthropogenic CO2 emissions – This should come as no surprise because the pH estimates are largely derived from atmospheric CO2 concentrations (Orr et al., 2005). It has also been postulated that anthropogenic CO2 emissions will force an additional 0.7 unit decline in oceanic pH by the year 2100 (Caldeira et al., 2003).
Alarmist organizations like the National Resources Defense Council are hard at work extrapolating these oceanic pH model predictions into ecological nightmares…
Scientists predict the Arctic will become corrosive to some shelled organisms within a few decades, and the Antarctic by mid-century. This is pure chemistry; the vagaries of climate do not apply to this forecast.
OA is expected to impact commercial fisheries worldwide, threatening a food source for hundreds of millions of people as well as a multi-billion dollar industry. In the United States alone, ocean-related tourism, recreation and fishing are responsible for more than 2 million jobs.
Shellfish will be affected directly, thus impacting finfish who feed on them. For example, pteropods—tiny marine snails that are particularly sensitive to rises in acidity— comprise 60 percent of the diet for Alaska’s juvenile pink salmon. And this affects diets farther up the food chain, as a diminished salmon population would lead to less fish on our tables.
Coral reefs will be especially hard hit by ocean acidification. As ocean acidity rises, corals will begin to erode faster than they can grow, and reef structures will be lost worldwide. Scientists predict that by the time atmospheric CO2 reaches 560 parts per million (a level which could happen which could happen by mid-century; we are currently nearing 400 ppm), coral reefs will cease to grow and even begin to dissolve. Areas that depend on healthy coral reefs for food, shoreline protection, and lucrative tourism industries will be profoundly impacted by their loss.
This sounds like a serious threat… As have all of the other alarmist clarion calls to halt capitalism in the name of the most recent environmental cause célèbre. Just to be fair, before pitching Ocean Acidification into the dustbin of junk science along with Anthropogenic Global Warming, let’s look at the science.
The answers to the following questions will tell us whether or not CO2-driven ocean acidification is a genuine scientific concern:
- Is atmospheric CO2 acidifying the oceans?
- Is there any evidence that reefs and other marine calcifers have been damaged by CO2-driven ocean acidification and/or global warming?
- Does the geological record support the oceanic acidification hypothesis?
Is atmospheric CO2 acidifying the oceans?
Before we can answer this question, we have to understand a bit about how the oceans make limestone and other carbonate rocks. The Carbonate Compensation Depth (CCD or Lysocline) is the depth at which carbonate shells dissolve faster than they accumulate. That depth is primarily determined by several factors…
-Water temperature
-Depth (pressure)
-CO2 concentration
-pH (high pH values aid in carbonate preservation)
-Amount of carbonate sediment supply
-Amount of terrigenous sediment supply
Calcium carbonate solubility increases with increasing carbon dioxide content, lower temperatures, and increasing pressure.
What evidence do we have that the lysocline or CCD has been becoming shallower or that the oceans have been acidifying over the last 250 years? The answer is: Almost none.
Pelejero et al., 2005 found a cyclical correlation between pH and the PDO…
Is there any evidence that reefs and other marine calcifers have been damaged by CO2-driven ocean acidification and/or global warming?
Using the data from Pelejero et al., 2005, I found no correlation between pH and reef calcification rates…
And when sudden increases of atmospheric CO2 have been tested under laboratory conditions, “otoliths (aragonite ear bones) of young fish grown under high CO2 (low pH) conditions are larger than normal, contrary to expectation” (Checkley et al., 2009).
A recent paper in Geology (Ries et al., 2009) found an unexpected relationship between CO2 and marine calcifers. 18 benthic species were selected to represent a wide variety of taxa: “crustacea, cnidaria, echinoidea, rhodophyta, chlorophyta, gastropoda, bivalvia, annelida.” They were tested under four CO2/Ωaragonite scenarios:
409 ppm (Modern day)
606 ppm (2x Pre-industrial)
903 ppm (3x Pre-industrial)
2856 ppm (10x Pre-industrial)
7/18 were not adversely affected by 10x pre-industrial CO2: Calcification rates relative to modern levels were higher or flat at 2856 ppm for blue crab, shrimp, lobster, limpet, purple urchin, coralline red algae, and blue mussel.
6/18 were not adversely affected by 3x pre-industrial CO2: Calcification rates relative to modern levels were higher or flat at 903 ppm for halimeda, temperate coral, pencil urchin, conch, bay scallop and whelk.
3/18 were not adversely affected by 2x pre-industrial CO2: Calcification rates relative to modern levels were higher or flat at 903 ppm for hard clam, serpulid worm and periwinkle.
2/18 had very slight declines in calcification at 2x pre-industrial: Oyster and soft clam.
The effects on calcification rates for all 18 species were either negligible or positive up to 606 ppm CO2. Corals, in particular seemed to like more CO2 in their diets…
Neither coral species experienced negative effects to calcification rates at CO2 levels below 1,000 to 2,000 ppmv. The study reared the various species in experimental sea water using 4 different CO2 and aragonite saturation scenarios.
It appears that in addition to being plant food… CO2 is also reef food.
More CO2 in the atmosphere leads to something called “CO2 fertilization.” In an enriched CO2 environment, most plants end to grow more. The fatal flaw of the infamous “Hockey Stick” chart was in Mann’s misinterpretation of Bristlecone Pine tree ring chronologies as a proxy for temperature; when in fact the tree ring growth was actually indicating CO2 fertilization as in this example from Greek fir trees…
Coral reefs can only grow in the photic zone of the oceans because zooxanthellae algae use sunlight, CO2, calcium and/or magnesium to make limestone.
The calcification rate of Flinders Reef has increased along with atmospheric CO2 concentrations since 1700…
As the atmospheric CO2 concentration has grown since the 1700’s coral reef extension rates have also trended upwards. This is contrary to the theory that increased atmospheric CO2 should reduce the calcium carbonate saturation in the oceans, thus reducing reef calcification. It’s a similar enigma to the calcification rates of coccoliths and otoliths.
In all three cases, the theory or model says that increasing atmospheric CO2 will make the oceans less basic by increasing the concentration of H+ ions and reducing calcium carbonate saturation. This is supposed to reduce the calcification rates of carbonate shell-building organisms. When, in fact, the opposite is occurring in nature with reefs and coccoliths – Calcification rates are generally increasing. And in empirical experiments under laboratory conditions, otoliths grew (rather than shrank) when subjected to high levels of simulated atmospheric CO2.
In the cases of reefs and coccoliths, one answer is that the relatively minor increase in atmospheric CO2 over the last couple of hundred years has enhanced photosynthesis more than it has hampered marine carbonate geochemistry. However, the otoliths (fish ear bones) shouldn’t really benefit from enhanced photo-respiration. The fact that otoliths grew rather than shrank when subjected to high CO2 levels is a pretty good indication that the primary theory of ocean acidification has been tested and falsified.
Some may say, “Hey! That’s just one reef! Flinders reef is an outlier!” Fair point. So let’s look at a larger data set.
The January 2, 2009 issue of Science featured a paper, Declining Coral Calcification on the Great Barrier Reef, by Glenn De’ath, Janice M. Lough, Katharina E. Fabricius. This is from the abstract:
Reef-building corals are under increasing physiological stress from a changing climate and ocean absorption of increasing atmospheric carbon dioxide. We investigated 328 colonies of massive Porites corals from 69 reefs of the Great Barrier Reef (GBR) in Australia. Their skeletal records show that throughout the GBR, calcification has declined by 14.2% since 1990, predominantly because extension (linear growth) has declined by 13.3%. The data suggest that such a severe and sudden decline in calcification is unprecedented in at least the past 400 years.
I have not purchased the article and my free membership to the AAAS does not grant access to it; but I did find the database that appears to go with De’ath et al., 2009 in the NOAA Paleoclimatology library: LINK
Well… I downloaded the data to Excel and I calculated an annual average calcification rate for the 59 cores that are represented in the data set. This is what I came up with…
It is “cherry-picking” of the highest order, if that last data point really is the basis of this claim: “Their skeletal records show that throughout the GBR, calcification has declined by 14.2% since 1990, predominantly because extension (linear growth) has declined by 13.3%. The data suggest that such a severe and sudden decline in calcification is unprecedented in at least the past 400 years.”
Over the last 400+ years the Earth’s climate has warmed ~0.6°, mean sea level has risen by about 9 inches and the atmosphere has become about 100 ppmv more enriched with CO2; and the Great Barrier Reef has responded by steadily growing faster.
2. Rising Sea Level: The Great Barrier Reef likes the slight sea level rise since the depths of the Little Ice Age…
3. Rising Atmospheric CO2 Concentrations: The Great Barrier Reef likes the increase in CO2 levels since the depths of the Little Ice Age…
Does the geological record support the oceanic acidification hypothesis?
Average annual pH reconstructions and measurements from various Pacific Ocean locations:
60 million to 40 million years ago: 7.42 to 8.04 (Pearson et al., 2000)
23 million to 85,000 years ago: 8.04 to 8.31 (Pearson et al., 2000)
6,000 years ago to present: 7.91 to 8.28 (Liu et al., 2009)
1708 AD to 1988 AD: 7.91 to 8.17 (Pelejero et al., 2005)
2000 AD to 2007 AD: 8.10 to 8.40 (Wootton et al., 2008)
The low pH levels from 60 mya to 40 mya include the infamous Paleocene-Eocene Thermal Maximum (PETM). E ven then, the oceans did not actually “acidify;” the lowest pH was 7.42 (still basic).
The Paleocene-Eocene Thermal Maximum (PETM) was a period of significant global warming approximately 55 million years ago and has often been cited as a geological analogy for the modern threat of ocean acidification. There is solid evidence that the Lysocline “shoaled” or became shallower for a brief period of time during the PETM. Several cores obtained from the Walvis Ridge area in the South Atlantic during Ocean Drilling Program (ODP) Leg 208 contained a layer of red clay at the P-E boundary in the middle of an extensive carbonate ooze section (Zachos et al., 2005). This certainly indicates a disruption of the lysocline during the PETM; but it doesn’t prove that it was ocean acidification.
The PETM was a period of extensive submarine and subaerial volcanic activity (Storey et al., 2007) and pedogenic carbonate reconstructions do support the possibility that seafloor methane hydrates released by that volcanic activity may have sharply increased oceanic CO2 saturation.
But… The terrigenous paleobotanical evidence does not support elevated atmospheric CO2 levels during the PETM (Royer et al., 2001). The SI data indicate CO2 levels in North America to have been between 300 and 400 ppmv during the PETM.
So, the PETM may have been an example of ocean acidification… But there is NO evidence that it was caused by a sharp increase in atmospheric CO2 levels.
The range of oceanic pH variation over the last 200 years is well within the natural variation range over the last 7,000 years.
Some have asserted that there is no geological precedent; claiming atmospheric CO2 concentrations have risen faster in the last 150 years than at any time in recent geological history. Ice core-derived CO2 data certainly do indicate that CO2 has not risen above ~310 ppmv at any point in the last 600,000 years and that it varies little at the decade or century scale. However, there are other methods for estimating past atmospheric CO2 concentrations.
Plants “breathe” CO2 through microscopic epidermal pores called stomata. The density of plant stomata varies inversely with the atmospheric partial pressure of CO2. Several recent studies of plant stomata from living, herbarium and fossil samples of plant tissue have shown that atmospheric CO2 fluctuations comparable to that seen in the industrial era have been fairly common throughout the Holocene and Recent times.
Plant stomata measurements reveal large variations in atmospheric CO2 concentrations over the tast 2,000 years that are not apparent in ice core data (Kouwenberg, 2004)…
Century-scale fluctuations in atmospheric CO2 concentrations have also been demonstrated in the early Holocene (Wagner et al., 1999)…
If the plant stomata data are correct, the increase in atmospheric CO2 that has occurred over the last 150 years is not anomalous. Past CO2 increases of similar magnitude and rate have not caused ocean acidification. In fact, marine calcifers would probably take 3,000 ppmv CO2 in stride, just by making more limestone… Kind of like they did during the Cretaceous…
Once again, we have an environmental catastrophe that is entirely supported by predictive computer models and totally unsupported by correlative and empirical scientific data. We can safely pitch ocean acidification into the dustbin of junk science.
References
Reef data from:
De’ath, G., J.M. Lough, and K.E. Fabricius. 2009. Declining coral calcification on the Great Barrier Reef. Science, Vol. 323, pp. 116 – 119, 2 January 2009.
Lough, J.M. and D.J. Barnes, 2000. Environmental controls on growth of the massive coral Porites. Journal of Experimental Marine Biology and Ecology, 245: 225-243.
Lough, J.M. and D.J. Barnes, 1997. Several centuries of variation in skeletal extension, density and calcification in massive Porites colonies from the Great Barrier Reef: a proxy for seawater temperature and a background of variability against which to identify unnatural change. Journal of Experimental Marine Biology and Ecology, 211: 29-67.
Chalker, B.E. and D.J. Barnes, 1990.
Gamma densitometry for the measurement of coral skeletal density. Coral Reefs, 4: 95-100.
Temperature data from:
Moberg, A., D.M. Sonechkin, K. Holmgren, N.M. Datsenko and W. Karlén. 2005. Highly variable Northern Hemisphere temperatures reconstructed from low-and high-resolution proxy data. Nature, Vol. 433, No. 7026, pp. 613-617, 10 February 2005.
University of Alabama, Hunstville
Sea Level data from:
“Recent global sea level acceleration started over 200 years ago?”, Jevrejeva, S., J. C. Moore, A. Grinsted, and P. L. Woodworth (2008), Geophys. Res. Lett., 35, L08715, doi:10.1029/2008GL033611.
CO2 data from:
D.M. Etheridge, L.P. Steele, R.L. Langenfelds, R.J. Francey, J.-M. Barnola and V.I. Morgan. 1998. Historical CO2 records from the Law Dome DE08, DE08-2, and DSS ice cores. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A.
Dr. Pieter Tans, NOAA/ESRL (www.esrl.noaa.gov/gmd/ccgg/trends)
Other references:
Royer, et al., 2001. Paleobotanical Evidence for Near Present-Day Levels of Atmospheric CO2 During Part of the Tertiary. Science 22 June 2001: 2310-2313. DOI:10.112
Caldeira, K. and Wickett, M.E. 2003. Anthropogenic carbon and ocean pH. Nature 425: 365.
Orr, J.C., et al., 2005. Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms. Nature 437, 681-686 (29 September 2005) | doi:10.1038
Pelejero, C., Calvo, E., McCulloch, M.T., Marshall, J.F., Gagan, M.K., Lough, J.M. and Opdyke, B.N. 2005.
Preindustrial to modern interdecadal variability in coral reef pH. Science 309: 2204-2207.
Zachos, et al., 2005. Rapid Acidification of the Ocean During the Paleocene-Eocene Thermal Maximum . Science 10 June 2005: 1611-1615. DOI:10.1126
Storey, et al., 2007. Paleocene-Eocene Thermal Maximum and the Opening of the Northeast Atlantic. Science 27 April 2007: 587-589. DOI:10.1126
Late 20th-Century Acceleration in the Growth of Greek Fir Trees. Volume 11, Number 49: 3 December 2008, CO2 Science
Iglesias-Rodriguez, et al., 2008. Phytoplankton Calcification in a High-CO2 World. Science 18 April 2008: 336-340 DOI:10.1126
Koutavas, A. 2008. Late 20th century growth acceleration in greek firs (Aibes cephalonica) from Cephalonia Island, Greece: A CO2 fertilization effect? Dendrochronologia 26: 13-19.
The Ocean Acidification Fiction. Volume 12, Number 22: 3 June 2009, CO2 Science
Checkley, et al., 2009. Elevated CO2 Enhances Otolith Growth in Young Fish. Science 26 June 2009: 1683. DOI:10.1126
Liu, Y., Liu, W., Peng, Z., Xiao, Y., Wei, G., Sun, W., He, J. Liu, G. and Chou, C.-L. 2009. Instability of seawater pH in the South China Sea during the mid-late Holocene: Evidence from boron isotopic composition of corals. Geochimica et Cosmochimica Acta 73: 1264-1272.
Ries, J.B., A.L. Cohen, D.C. McCorkle. Marine calcifiers exhibit mixed responses to CO2-induced ocean acidification. Geology 2009 37: 1131-1134.
Excellent post. Hope to see it published in a journal.
Dave Bob says:
January 11, 2011 at 8:59 am
Coral is actually a symbiotic relationship between plants and animals. The coral critters themselves can’t photosynthesize, so they team up with a kind of being called “zooxanthella”. (I guess they don’t mind being called “zooxanthella”, but I would have changed it as soon as I got past Customs and Immigration … but I digress.)
In any case, the zooxanthella do the photosynthesizing, and the corals do the harmonizing. So is the whole reef a plant or an animal? Well, it’s both, what we used to call a “morphodite” when I was a kid.
Q. Where do freshwater mussels live?
A. If you said “in fresh water” then you can give yourself a point.
Q. Are they creatures with a shell?
A. Evidently not given that fresh water can have a pH as low as 6 without being unusual. (/sarc)
What a fantastic post!
bDavid Middleton says:
January 11, 2011 at 9:46 am
“Correction to my correction to my comments on Ries et al., 2009…
7/18 were not adversely affected by 10x pre-industrial CO2: Calcification rates relative to modern levels were higher or flat at 2856 ppm for lobster, blue crab, shrimp, limpet, purple urchin, coralline red algae, and blue mussel.”
In this I have no complaints.
“6/18 were not adversely affected by 3x pre-industrial CO2: Calcification rates relative to modern levels were higher or flat at 903 ppm for halimeda, temperate coral, pencil urchin, conch, bay scallop and whelk.”
Actually pencil urchin, conch, bay scallop and whelk show decreases in calcification. Some conch even show slight negative calcification (i.e. dissolution) at 3x pre-industrial CO2.
“3/18 were not adversely affected by 2x pre-industrial CO2: Calcification rates relative to modern levels were higher or flat at 903 ppm for hard clam, serpulid worm and periwinkle.”
Actually this is true only for serpulid worm. Hard clam and periwinkle show decresases in calcification.
“2/18 had very slight declines in calcification at 2x pre-industrial: Oyster and soft clam.”
Actually this happens also for other organisms: whelk, bay scallop, periwinkle, conch (that in some cases turns to dissolution) hard clam, pencil urchin (this last show reduced maximum, not average calcification)
The spread in the data for a given aragonite saturation is high, even higher than the trends observed for some organisms. This can confuse the reader if he has not extreme attention to the graphs (I personally checked the graphs more than 5 times as I wrote this comment).
To make a review of the results of the Ries et al paper: “Marine calcifiers exhibit mixed responses to CO2-induced ocean acidification”
3/18 organisms (blue crab, shrimp, lobster) show increased calcification with decreasing aragonite saturation state.
4/18 organisms (limpet, purple urchin,corallalline red algae, halimeda) show a “parabolic” response: as pCO2 increases, first the calcification increases then, approaching aragonite undersaturation, the calcification decreases. At 10x pre-industrial pCO2, for coralline red algae , the calcification rate is back to pre-industrial values. For Halimeda, it drops by 80%. For limpet and purple urchin, the calcification is still higher than pre-industrial.
For 1/18 organisms (blue mussel) the aragonite saturation state has no effect.
For 10/18 organisms, the reduced aragonite saturation state causes a reduction in calcification. Of these , 6/18 organisms (soft clam, whelk, oyster, bay scallop, periwinckle, serpulid worm) show a near linear decrease of calcification as alkalinity drops. The other 4/18 (temperate coral, pencil urchin, hard clam, conch) organisms show a non-linear decrease, that began as a slight decrease and after a treshold at roughly 3-4x pre-industrial pCO2 the calcification rate decreases significantly.
Of the organisms that show decreased calcification, 6/18 show negative calcification (that is, dissolution): pencil urchin (that begins at roughly 4x pre-industrial pCO2), hard clam (that begins at roughly 3-4x pre-industrial pCO2), conch (that begins at roughly 2-4x pre-industrial pCO2), periwinkle (that begins at roughly 3x pre-industrial pCO2), whelk (that begins at roughly 3x pre-industrial pCO2), soft clam (that begins at roughly 2.5-3x pre-industrial pCO2).
The results, as the title of the study make clear, show that ocean acidification is neither an “universal killer” nor “reef food”. Instead, some calcifiers win, other lose. As the oceans acidify due to the increasing pCO2, the ecosistems will change, driving some species to extinction, while other will be benefited.
The problems is that changes due to the CO2 produced by the burning of fossil fuels are too fast for ecosystems to adapt, and the demise of some species the rise of some others in a so short times (compared to geologic timescales) could potentially disrupt the ecosystems, with unpredictable consecuences.
That is the humans determine, with that some species go extinct while others prosper
(continuation)
That the humans determine, with the CO2 pollution, that some species go extinct while others prosper is to me playing God. And this “games” almost always end in tragedy.
From Peru is under the illusion that CO2 is “pollution.”
If that is the level of his understanding then he knows nothing about science.
ShrNfr says:
No…What matters is the partial pressure of the CO2, which increases as its concentration in the atmosphere increases.
Patrick says:
Or maybe they just understand the science better and thus know that the acidification has to do with the rate of rise of CO2 more than the absolute magnitude. The leaching of CaCO3 from the land acts to counter the acidification but, alas, the timescale for this to occur is too slow for the sort of rapid change that we are producing in atmospheric (and ocean mixed layer) CO2 levels.
Smokey:
High pCO2 is lethal to some species (they lose their shells by dissolution) as shown in the paper that I have discussed above. If something that can cause extinction to some species (actually the worst thing that can happen with a species) is not pollution, then what “pollution” mean to you?
Grumbler says:
January 11, 2011 at 8:55 am
While the models are simple, they are not dumb. Well, not that dumb at least. Whatever CO2 goes into the ocean is not counted in the air.
Peru:
It doesn’t matter what pollution means to me. What matters is the definition of pollution. From my on-line dictionary:
Pollution: n. The presence in or introduction into the environment of a substance or thing that has harmful or poisonous effects.
In the concentrations being discussed, CO2 is neither harmful nor poisonous.
Manwichstick says:
January 11, 2011 at 10:15 am
Manwichstick, I find David’s statement more supported by the data than Ries’s statement. Ries’s statement is nothing but a an alarmist claim about future possibilites. Let me make my corresponding claim:
My statement is just as likely as Ries’s statement to be true, and neither statement is verifiable. In addition, there is nothing in the data to support either my statement or Ries’s statement. Not one word. He didn’t study that question, he has no data on that question, he presents no authorities on that question. His claim is nothing but a statement about possibilities in a future universe, and as such it is exactly as valid as my statement.
David’s statement, on the other hand, is supported by the data. Despite claims that coral reef growth would slow with increasing pCO2 in the water, that’s not happening. Instead, coral growth rates seem to be higher with increasing pCO2.
Call me crazy, but given my choice, I pick folks who base their statements on the data, not on a desire to frighten us with scary scenarios of future imagined problems …
w.
From Peru says:
January 11, 2011 at 4:38 pm
Oh, please. You were doing so well up to that point, with an interesting analysis of the Ries paper.
However, high nitrogen levels can kill you too, try breathing 98% nitrogen sometimes … but that doesn’t make nitrogen a “pollutant”.
Smokey:
Did “shell dissolution” isn’t enough harmful to you?
Maybe you don’t care because you don’t have a shell. Give away your antropocentrism for a moment.
In the concentrations being discussed, CO2 is neither harmful nor poisonous
In the concentrations discussed, between 2-10x pre-industrial pCO2, some shelled organisms studied showed reduced calcification and even dissolution. I extracted from the paper this:
“Of the organisms that show decreased calcification, 6/18 show negative calcification (that is, dissolution): pencil urchin (that begins at roughly 4x pre-industrial pCO2), hard clam (that begins at roughly 3-4x pre-industrial pCO2), conch (that begins at roughly 2-4x pre-industrial pCO2), periwinkle (that begins at roughly 3x pre-industrial pCO2), whelk (that begins at roughly 3x pre-industrial pCO2), soft clam (that begins at roughly 2.5-3x pre-industrial pCO2)”.
This result is valid for the temperate and tropical ocean. For the cold polar ocean (cold water dissolves CO2 more than warm water), the situation is much worse. A few years ago was believed :
“Scientists predict the Arctic will become corrosive to some shelled organisms within a few decades, and the Antarctic by mid-century”
Now it turned that the Arctic is ALREADY corrosive for aragonite-shelled organisms. The “alarmist” predictions were actually overoptimistic. See this paper:
Aragonite Undersaturation in the Arctic Ocean- Effects of Ocean Acidification and Sea Ice Melt
http://www.whoi.edu/beaufortgyre/pdfs/yamamoto-kawai_aragonite_science2009.pdf
The abstract says:
“The increase in anthropogenic carbon dioxide emissions and attendant increase in ocean acidification and sea ice melt act together to decrease the saturation state of calcium carbonate in the Canada Basin of the Arctic Ocean. In 2008, surface waters were undersaturated with respect to aragonite, a relatively soluble form of calcium carbonate found in plankton and invertebrates. Undersaturation was found to be
a direct consequence of the recent extensive melting of sea ice in the Canada Basin. In addition, the retreat of the ice edge well past the shelf-break has produced conditions favorable to enhanced upwelling of subsurface, aragonite-undersaturated water onto the Arctic continental shelf. Undersaturation will affect both planktonic and benthic calcifying biota and therefore the composition of the Arctic ecosystem”
We are in 2011. The Arctic become aragonite-undersaterated already in 2008.
Joel Shore says:
January 11, 2011 at 4:29 pm
Joel is right, the issue is pCO2, although as you point out the temperature also plays a part.
Or maybe they don’t understand the science better … from Nature Magazine, “Atmospheric carbon dioxide concentrations over the past 60 million years” (PDF), here is a graph of geological oceanic pH levels.
Where is the neutralization by CaCO3 you are talking about? For twenty million years, a third of this record, the pH was way lower than it is today. Was the CaCO3 taking a holiday? …
w.
Manwichstick – did you read the paper, or did you read the abstract? The abstract bases its conclusion upon the hypothetical situation in which C02 = 10x pre-industrial levels. Strange logic… one might similarly conclude that water is harmful to human beings, since in quantity it can kill.
More relevant is the response of calcification rates to current or predicted C02 levels – all far less than 2400 ppm – and this is the tack the author here took.
Senior marine researcher has accused Australian scientists of “crying wolf” over the threat of climate change to the Great Barrier Reef,
..
Peter Ridd’s rejection of the consensus position that the reef is doomed unless greenhouse emissions are checked comes as new research on the Keppel group, hugging Queensland’s central coast, reveals its resilience after coral bleaching.
http://www.theaustralian.com.au/national-affairs/climate/scientists-crying-wolf-over-coral-e6frg6xf-1225811910634
Media circus when ships crash into reef and oil spills
http://www.quadrant.org.au/blogs/doomed-planet/2010/04/farce-on-the-reef
http://blogs.news.com.au/heraldsun/andrewbolt/index.php/heraldsun/comments/catastrophic_slick_of_hype_detected_on-barrier-reef
Willis Eschenbach said:
“Where is the neutralization by CaCO3 you are talking about? For twenty million years, a third of this record, the pH was way lower than it is today. Was the CaCO3 taking a holiday?”
Well said!
The current CO2 concentrations are unprecedented in the last 15 million years, as is shown also in this article:
“Coupling of CO2 and Ice Sheet Stability Over Major Climate Transitions of the Last 20 Million Years”
http://atripati.bol.ucla.edu/23.pdf
This shows that last time the concentration of CO2 were similar to those of today were in the Mid-Miocene Climatic Optimum (15 million years ago). Then the condition were:
“When pCO2 levels were last similar to modern values (that is, greater than 350 to 400 ppmv), there was little glacial ice on land or sea ice in the Arctic, and a marine-based ice mass on Antarctica was not viable. A sea ice cap on the Arctic Ocean and a large permanent ice sheet were maintained on East Antarctica when pCO2
values fell below this threshold. Lower levels were necessary for the growth of large ice masses on West Antarctica (~250 to 300 ppmv) and Greenland (~220 to 260 ppmv). (…) During theMid-Miocene, when pCO2 was apparently grossly similar to
modern levels, global surface temperatures were, on average, 3 to 6°C warmer than in the present”
For the “skeptics” I have the following question:
How could we erase 15 million years of decline in CO2 concentrations in just 200 years without disrupting the Climate and Ocean chemistry?
Dave – Great post, thanks for taking the time.
@From Peru.
Your comments are of interest and are relevant to the interpretations from Ries’s paper, but I think you are missing the overall point. Consider that the geologic record shows similar wide ranges of CO2 values and as has been pointed out carbonate-forming organisms have not gone extinct. Yes, perhaps the examples discussed in the paper show lobsters do better than hard clams, but then perhaps we should reserve judgment until the experiment is repeated and a larger body of evidence over species calcification rates is collected. Next we will need to prove that calcification rates equate to extinction, remembering, of course that both lobsters and hard clams have been present in the geologic record since the Paleozoic surviving despite your concerns.
But having asked you to reserve judgment on the science, don’t you think that a broader examination of your worldview is in order. Your concern over extinction is touching yet a little naive – after all, extinction has been the fate of 99% of all species that have ever lived on Earth and is the way the world works. Or perhaps you think that humanity has a responsibility to stop every extinction that can or potentially will occur, regardless of how well established the cause is. At some point your argument is as ridiculous as certain Buddhist monks who sweep the path in front of them for fear of stepping on (and killing) an ant. Imagine you are one of those monks – why would you ever get out of bed in the morning? Walking to the outhouse is the moral equivalent of crossing a mine field.
Finally, if your nature is to quibble about science and question possible outcomes, you have a far richer target environment questioning the hysteria over ocean acidification than the obstacles you have raised thus far.
None of this matters, because AR5 under WGII co-chair, Chris Field, the founding director of the Carnegie Institution’s Department of Global Ecology where Dr. Caldeira is based, already says:
“The next IPCC assessment will benefit from more ocean science. We now know that increasingly acidic seas are reducing coral reef health and changing ocean ecosystems. But will the increasing CO2 uptake by the ocean and warmer oceans also bring risks for all life on Earth?”
The Technical Support Unit, (TSU) for WGII is also based at the Carnegie Institution.
There are videos for schools on the subject, showing how pieces of coral will dissolve in a flask of vinegar, with lots of nice bubbles.
For more on the political scientists behind this, check out
http://scienceandpublicpolicy.org/originals/acid_seas.html?Itemid=0
It is guaranteed that the next IPCC summary for policy makers will make unequivocal statements that ocean acidification is real.
Willis Eschenbach says:
January 11, 2011 at 6:00 pm
“However, high nitrogen levels can kill you too, try breathing 98% nitrogen sometimes … but that doesn’t make nitrogen a “pollutant”.”
As far I know, an atmosphere of 98% nitrogen can kill you not because there is too much nitrogen (if it were the case, diving would be deadly, as the N2 pressure increases with depth) but because there is too little oxygen.
In the case of CO2 instead, too much of it IS deadly. For humans the concentration must be very high (roughly 10%), but for some marine creatures, as shown in the Ries paper , concentration as low as 2x pre-industrial CO2 or 3x pre-industrial CO2 can dissolve their shells.
And these concentrations of CO2 will be reached in a few decades if CO2 emissions are not reduced.
You posted an interesting paper. It shows that for 15 million years the concentrations of CO2 were lower than the current ones. It is reasonable to suspect than one cannot erase 15 million years of declining CO2 concentrations in just 200 years without disrupting the climate and ocean chemistry.
From ” From Peru” on January 12, 2011 at 8:36 am:
Then they shall be reached, as China and many other countries have decided to not participate in the schemes to reduce their own carbon (dioxide) emissions. Therefore the issue is moot. The atmospheric concentrations of CO2 shall continue to rise, whatever consequences shall befall the oceans shall happen.
Game over. Thank you for playing.
From peru,
You’re not making sense. Co2 is as necessary for life as h20. Too much of anything can cause problems.
Kadaka is right, too. All the attacks and attempts to demonize c02 are directed at Western countries, especially the US, which is 99.9% pollution free (and c02 is not pollution, except in the beliefs of the eco-fringe).
China is the #1 c02 emitter, way ahead of other countries, and China is building
2 – 4 new coal power plants every week, with very little in the way of emission controls. But the c02 alarmists never seem to care about China’s c02 emissions, proving that their attempts to demonize a harmless trace gas, necessary to all life, is nothing but a political attack.
When the majority of posts complaining about c02 start targeting China and India and Brazil and Russia instead of the clean US, we’ll start to believe you’re sincere. But up to now you don’t have any sincerity, only misplaced blame. We’re on to you.
kadaka (KD Knoebel) says:
January 12, 2011 at 11:56 am
“Then they shall be reached, as China and many other countries have decided to not participate in the schemes to reduce their own carbon (dioxide) emissions. Therefore the issue is moot.”
Not quite. China is not willing to reduce its emissions because the developed courties like the USA don’t want to reduce their emissions first.
The developed countries have more responsability for CO2 pollution than developing courties like China and India, because the developed countries began emitting CO2 200 years ago (in the Industrial Revolution) while China and India began their massive emissions just a few decades ago. So the cumulative emissions (that are what the planet feels) are far bigger for the developed word than for the developing nations.
So the developed nations must do the first step (as are beginning to do in Europe). This do not mean that developing nations should emit CO2 without restrictions. They should follow the example of the developed nations.
The developing nations that do not have abundant resources to develop clean tecnologies should be aided by developed nations. This is the much maligned “wealth redistribution” that was discussed in Cancun.
Let’s make an historical note: for centuries the current developed nations redistributed wealth from the poor to the rich. The resources of my country were depredated for centuries by the Spanish, until independence. Then a series of corrupt governments privileged a restricted oligarchy (the remnant of the Spanish social system) while the common people lived in total poverty. Africa took a much harder hit: the very people there were sold as slaves, then a century after (late 1800s) their territory invaded, and many of the survivors of the first imperialist wave (that of the 1500s-1700s) were then exploited in their own territory. The destruction of Africa was one of the most horrendous crimes committed by the Western “Civilization”. This is theft and murder at an astonishing scale.
Now the West have the opportunity to repair part of the damage done, aiding the poor nations to develop an economy without paying the social (an unequal growth) and ecological (pollution) price that the industrialized nations paid during the Industrial Revolution.
My country (Peru) in the last 10 years is enjoying a period of sustained growth after the downfall of the last corrupt dictatorship in the year 2000. This growth is still precarious, as it is unequal (causing increasing social turmoil) and dependent on fossil fuels. Lima is already one the most polluted cities in the world, there is extensive deforestation in the Peruvian Amazon, and the pollution costs are equal to 4% of our Gross Domestic Product.
The economic aid would be a great help to halt deforestation and change from polluting oil fuel for transportation to the more environmental-friendly natural gas (we have big gas resources). Building big solar, wind and hydroelectric facilities can make all our electricty from renewable sources (already hydropower makes half our electricity) leaving the our limited natural gas to transportation and petrochemicals.
“The atmospheric concentrations of CO2 shall continue to rise, whatever consequences shall befall the oceans shall happen.”
No it not. The potential disruption caused by climate change and ocean acidification will cause an inaceptable cost, specially to poor nations like mine.
“Game over. Thank you for playing”
It is still not over. But big carbon (dioxide) emitters are playing with the future of countless lifeforms on Earth, and with the future of vulnerable countries like mine.