Nature Geoscience study: Oceans are acidifying 10 times faster today than 55 million years ago when a mass extinction of marine species occurred

Unrestricted burning of fossil fuels threatens a new wave of die-offs

Marine life face some of the worst impacts.  We now know that global warming is “capable of wrecking the marine ecosystem and depriving future generations of the harvest of the seas” (see 2009 Nature Geoscience study concludes ocean dead zones “devoid of fish and seafood” are poised to expand and “remain for thousands of years”).

The acidification of the ocean in particular is a grave threat  — for links to primary sources and recent studies, see “Imagine a World without Fish: Deadly ocean acidification “” hard to deny, harder to geo-engineer, but not hard to stop” (and below).

A new Nature Geoscience study, “Past constraints on the vulnerability of marine calcifiers to massive carbon dioxide release” (subs. req’d) provides a truly ominous warning.  The release from the researchers at the University of Bristol is “Rate of ocean acidification the fastest in 65 million years.”

I am reprinting below a piece by award-winning science journalist Carl Zimmer published this week by Yale environment360, which explains ocean acidification and what this important study says:

The JOIDES Resolution looks like a bizarre hybrid of an oil rig and a cargo ship. It is, in fact, a research vessel that ocean scientists use to dig up sediment from the sea floor. In 2003, on a voyage to the southeastern Atlantic, scientists aboard the JOIDES Resolution brought up a particularly striking haul.

They had drilled down into sediment that had formed on the sea floor over the course of millions of years. The oldest sediment in the drill was white. It had been formed by the calcium carbonate shells of single-celled organisms “” the same kind of material that makes up the White Cliffs of Dover. But when the scientists examined the sediment that had formed 55 million years ago, the color changed in a geological blink of an eye.

“In the middle of this white sediment, there’s this big plug of red clay,” says Andy Ridgwell, an earth scientist at the University of Bristol.

In other words, the vast clouds of shelled creatures in the deep oceans had virtually disappeared. Many scientists now agree that this change was caused by a drastic drop of the ocean’s pH level. The seawater became so corrosive that it ate away at the shells, along with other species with calcium carbonate in their bodies. It took hundreds of thousands of years for the oceans to recover from this crisis, and for the sea floor to turn from red back to white.

The clay that the crew of the JOIDES Resolution dredged up may be an ominous warning of what the future has in store. By spewing carbon dioxide into the air, we are now once again making the oceans more acidic.

Today, Ridgwell and Daniela Schmidt, also of the University of Bristol, are publishing a study in the journal Nature Geoscience, comparing what happened in the oceans 55 million years ago to what the oceans are

experiencing today. Their research supports what other researchers have long suspected: The acidification of the ocean today is bigger and faster than anything geologists can find in the fossil record over the past 65 million years. Indeed, its speed and strength “” Ridgwell estimate that current ocean acidification is taking place at ten times the rate that preceded the mass extinction 55 million years ago “” may spell doom for many marine species, particularly ones that live in the deep ocean.

“This is an almost unprecedented geological event,” says Ridgwell.

When we humans burn fossil fuels, we pump carbon dioxide into the atmosphere, where the gas traps heat. But much of that carbon dioxide does not stay in the air. Instead, it gets sucked into the oceans. If not for the oceans, climate scientists believe that the planet would be much warmer than it is today. Even with the oceans’ massive uptake of CO2, the past decade was still the warmest since modern record-keeping began. But storing carbon dioxide in the oceans may come at a steep cost: It changes the chemistry of seawater.

At the ocean’s surface, seawater typically has a pH of about 8 to 8.3 pH units. For comparison, the pH of pure water is 7, and stomach acid is around 2. The pH level of a liquid is determined by how many positively charged hydrogen atoms are floating around in it. The more hydrogen ions, the lower the pH. When carbon dioxide enters the ocean, it lowers the pH by reacting with water.

The carbon dioxide we have put into the atmosphere since the Industrial Revolution has lowered the ocean pH level by .1. That may seem tiny, but it’s not. The pH scale is logarithmic, meaning that there are 10 times more hydrogen ions in a pH 5 liquid than one at pH 6, and 100 times more than pH 7. As a result, a drop of just .1 pH units means that the concentration of hydrogen ions in the ocean has gone up by about 30 percent in the past two centuries.

To see how ocean acidification is going to affect life in the ocean, scientists have run laboratory experiments in which they rear organisms at different pH levels. The results have been worrying “” particularly for species that build skeletons out of calcium carbonate, such as corals and amoeba-like organisms called foraminifera. The extra hydrogen in low-pH seawater reacts with calcium carbonate, turning it into other compounds that animals can’t use to build their shells.

These results are worrisome, not just for the particular species the scientists study, but for the ecosystems in which they live. Some of these vulnerable species are crucial for entire ecosystems in the ocean. Small shell-building organisms are food for invertebrates, such as mollusks and small fish, which in turn are food for larger predators. Coral reefs create an underwater rain forest, cradling a quarter of the ocean’s biodiversity.

But on their own, lab experiments lasting for a few days or weeks may not tell scientists how ocean acidification will affect the entire planet. “It’s not obvious what these mean in the real world,” says Ridgwell.

One way to get more information is to look at the history of the oceans themselves, which is what Ridgwell and Schmidt have done in their new study. At first glance, that history might suggest we have nothing to worry about. A hundred million years ago, there was over five times more carbon dioxide in the atmosphere and the ocean was .8 pH units lower. Yet there was plenty of calcium carbonate for foraminifera and other species. It was during this period, in fact, that shell-building marine organisms produced the limestone formations that would eventually become the White Cliffs of Dover.

But there’s a crucial difference between the Earth 100 million years ago and today. Back then, carbon dioxide concentrations changed very slowly over millions of years. Those slow changes triggered other slow changes in the Earth’s chemistry. For example, as the planet warmed from more carbon dioxide, the increased rainfall carried more minerals from the mountains into the ocean, where they could alter the chemistry of the sea water. Even at low pH, the ocean contains enough dissolved calcium carbonate for corals and other species to survive.

Today, however, we are flooding the atmosphere with carbon dioxide at a rate rarely seen in the history of our planet. The planet’s weathering feedbacks won’t be able to compensate for the sudden drop in pH for hundreds of thousands of years.

Scientists have been scouring the fossil record for periods of history that might offer clues to how the planet will respond to the current carbon jolt. They’ve found that 55 million years ago, the Earth went through a similar change. Lee Kump of Penn State and his colleagues have estimated that roughly 6.8 trillion tons of carbon entered the Earth’s atmosphere over about 10,000 years.

Nobody can say for sure what unleashed all that carbon, but it appeared to have had a drastic effect on the climate. Temperatures rose between 5 and 9 degrees Celsius (9 to 16 Fahrenheit). Many deep-water species became extinct, possibly as the pH of the deep ocean became too low for them to survive.

But this ancient catastrophe (known as the Paleocene-Eocene thermal maximum, or PETM) was not a perfect prequel to what’s happening on Earth today. The temperature was warmer before the carbon bomb went off, and the pH of the oceans was lower. The arrangement of the continents was also different. The winds blew in different patterns as a result, driving the oceans in different directions. All these factors make a big difference on the effect of ocean acidification. For example, the effect that low pH has on skeleton-building organisms depends on the pressure and temperature of the ocean. Below a certain depth in the ocean, the water becomes so cold and the pressure so high that there’s no calcium carbonate left for shell-building organisms. That threshold is known as the saturation horizon.

To make a meaningful comparison between the PETM and today, Ridgwell and Schmidt built large-scale simulations of the ocean at both points of time. They created a virtual version of the Earth 55 million years ago and let the simulation run until it reached a stable state. The pH level of their simulated ocean fell within the range of estimates of the pH of the actual ocean 55 millions years ago. They then built a version of the modern Earth, with today’s arrangements of continents, average temperature, and other variables. They let the modern world reach a stable state and then checked the pH of the ocean. Once again, it matched the real pH found in the oceans today.

Ridgwell and Schmidt then jolted both of these simulated oceans with massive injections of carbon dioxide. They added 6.8 trillion tons of carbon over 10,000 years to their PETM world. Using conservative projections of future carbon emissions, they added 2.1 trillion tons of carbon over just a few centuries to their modern world. Ridgwell and Schmidt then used the model to estimate how easily carbonate would dissolve at different depths of the ocean.

The results were strikingly different. Ridgwell and Schmidt found that ocean acidification is happening about ten times faster today than it did 55 million years ago. And while the saturation horizon rose to 1,500 meters 55 million years ago, it will lurch up to 550 meters on average by 2150, according to the model.

The PETM was powerful enough to trigger widespread extinctions in the deep oceans. Today’s faster, bigger changes to the ocean may well bring a new wave of extinctions. Paleontologists haven’t found signs of major extinctions of corals or other carbonate-based species in surface waters around PETM. But since today’s ocean acidification is so much stronger, it may affect life in shallow water as well. “We can’t say things for sure about impacts on ecosystems, but there is a lot of cause for concern,” says Ridgwell.

Ellen Thomas, a paleoceanographer at Yale University, says that the new paper “is highly significant to our ideas on ocean acidification.” But she points out that life in the ocean was buffeted by more than just a falling pH. “I’m not convinced it’s the whole answer,” she says. The ocean’s temperature rose and oxygen levels dropped. Together, all these changes had complex effects on the ocean’s biology 55 million years ago. Scientists now have to determine what sort of combined effect they will have on the ocean in the future.

Our carbon-fueled civilization is affecting life everywhere on Earth, according to the work of scientists like Ridgwell “” even life that dwells thousands of feet underwater. “The reach of our actions can really be quite global,” says Ridgwell. It’s entirely possible that the ocean sediments that form in the next few centuries will change from the white of calcium carbonate back to red clay, as ocean acidification wipes out deep-sea ecosystems.

“It will give people hundreds of millions of years from now something to identify our civilization by,” says Ridgwell.

And for completeness’ sake, here’s more background on ocean acidification (which regular CP readers can skip).   You can watch NOAA administrator Lubchenco give a demonstration of the science of ocean acidification.

Ocean acidification must be a core climate message, since it is hard to deny and impervious to the delusion that geoengineering is the silver bullet.  Indeed, a major 2009 study GRL study, “Sensitivity of ocean acidification to geoengineered climate stabilization” (subs. req’d), concluded:

The results of this paper support the view that climate engineering will not resolve the problem of ocean acidification, and that therefore deep and rapid cuts in CO2 emissions are likely to be the most effective strategy to avoid environmental damage from future ocean acidification.

If you want to understand ocean acidification better, see this BBC story, which explains:

Man-made pollution is raising ocean acidity at least 10 times faster than previously thought, a study says.

Or see this Science magazine study, “Evidence for Upwelling of Corrosive “Acidified” Water onto the Continental Shelf” (subs. req’), which found

Our results show for the first time that a large section of the North American continental shelf is impacted by ocean acidification. Other continental shelf regions may also be impacted where anthropogenic CO2-enriched water is being upwelled onto the shelf.

Or listen to the Australia’s ARC Centre of Excellence for Coral Reef Studies, which warns:

The world’s oceans are becoming more acid, with potentially devastating consequences for corals and the marine organisms that build reefs and provide much of the Earth’s breathable oxygen.

The acidity is caused by the gradual buildup of carbon dioxide (CO2) in the atmosphere, dissolving into the oceans. Scientists fear it could be lethal for animals with chalky skeletons which make up more than a third of the planet’s marine life”¦.

Corals and plankton with chalky skeletons are at the base of the marine food web. They rely on sea water saturated with calcium carbonate to form their skeletons. However, as acidity intensifies, the saturation declines, making it harder for the animals to form their skeletal structures (calcify).

Analysis of coral cores shows a steady drop in calcification over the last 20 years,” says Professor Ove Hoegh-Guldberg of CoECRS and the University of Queensland. “There’s not much debate about how it happens: put more CO2 into the air above and it dissolves into the oceans.

When CO2 levels in the atmosphere reach about 500 parts per million, you put calcification out of business in the oceans.” (Atmospheric CO2 levels are presently 385 ppm, up from 305 in 1960.)

I’d like to see an analysis of what happens when you get to 850 to 1000+ ppm because that is where we’re headed (see U.S. media largely ignores latest warning from climate scientists: “Recent observations confirm “¦ the worst-case IPCC scenario trajectories (or even worse) are being realised” “” 1000 ppm).

In June, dozens of Academies of Science, including ours and China’s, issued a joint statement on ocean acidification, warned “Marine food supplies are likely to be reduced with significant implications for food production and security in regions dependent on fish protein, and human health and wellbeing” and “Ocean acidification is irreversible on timescales of at least tens of thousands of years.”  They conclude:

Ocean acidification is a direct consequence of increasing atmospheric CO2 concentrations. To avoid substantial damage to ocean ecosystems, deep and rapid reductions of global CO2 emissions by at least 50% by 2050, and much more thereafter are needed.

We, the academies of science working through the InterAcademy Panel on International Issues (IAP), call on world leaders to:

“¢ Acknowledge that ocean acidification is a direct and real consequence of increasing atmospheric CO2 concentrations, is already having an effect at current concentrations, and is likely to cause grave harm to important marine ecosystems as CO2 concentrations reach 450 ppm and above;

“¢ Recognise that reducing the build up of CO2 in the atmosphere is the only practicable solution to mitigating ocean acidification;

“¢ Within the context of the UNFCCC negotiations in the run up to Copenhagen 2009, recognise the direct threats posed by increasing atmospheric CO2 emissions to the oceans and therefore society, and take action to mitigate this threat;

“¢ Implement action to reduce global CO2 emissions by at least 50% of 1990 levels by 2050 and continue to reduce them thereafter.

If we want to save life in the oceans “” and save ourselves, since we depend on that life “” the time to start slashing carbon dioxide emissions is now.

27 Responses to Nature Geoscience study: Oceans are acidifying 10 times faster today than 55 million years ago when a mass extinction of marine species occurred

  1. PSU Grad says:

    By strange coincidence one anti-science poster on a local newspaper (who refuses to identify himself) posts this:

    “Coral reefs dying because of climate change? Yes, they are dying from climate change………..from the adverse affect of cooling water, not CO2, most recently in Florida. CO2 is necessary for corals and their symbiotic algae to precipitate calcite and aragonite (calcium carbonate compounds). The myth of CO2 acidification of ocean water and causing harm to corals is easily debunked. Only those that fail to study and understand environmental chemistry can believe such ridiculous claims.

    As for media coverage, most mainstream media outlets (ABC, CBS, MSNBC, CNN, NYT) favor the carbon hysteria side of things. On can learn nothing from those outlets of the recent Phil Jones (CRU, IPCC) admissions of error and lack of warming for example.

    As for peer review claims………given the repeated scandals, those claims appear no more valid now than one burglar vouching for the whereabouts of another burglar.”

    And also this:

    “Marine life killed by cold:

    I suspect this individual is actually from an ultra (uber?) conservative think tank who is being fed this information in order to appear to be a “scientist”.

  2. prokaryote says:

    Exactly this is why we need to tackle the climate crisis now.
    We have the technology. We need to tackle this now.

  3. fj2 says:

    It seems that sequestering CO2 from the oceans should have the highest priority coincident with immediate large scale emissions reduction.

    Just a quick guess but it seems that the oceans may serve as the best sequestering environments.

    Blue sky stuff:
    Yes, Joe doesn’t like geo-engineering and most if not all past proposals have been quite primitive and dangerous but there may be opportunities and living systems reproduce, come with the original nano machines, are self-organizing, and may be able to provide very powerful solutions as well as those employing non-living geosciences; of course, large-scale powerful environmental solutions have the potential to be very dangerous so advancement must be very sophisticated — read elegant and not overly complex; likely highly incremental — employing extreme caution.

  4. Shiny says:

    What percentage of CO2 is natural as opposed to man made that cycles through carbon cycle annually ?

  5. MarkB says:

    Another study on increased weather variability due to global warming:

    “It is anticipated that in a warmer world, blocking events will be more numerous, weaker and longer-lived,” Lupo said. “This could result in an environment with more storms. We also anticipate the variability of weather patterns will change dramatically over some parts of the world, such as North America, Europe and Asia, but not in others.”

    Water woes in the midwest:

    “Keith Cherkauer, an assistant professor of agricultural and biological engineering, ran simulation models that show Indiana, Illinois, Wisconsin and Michigan could see as much as 28 percent more precipitation by the year 2070, with much of that coming in the winter and spring. His projections also show drier summer and fall seasons.

    “This was already a difficult spring to plant because of how wet it was. If you were to add another inch or so of rain to that, it would be a problem,” said Cherkauer, whose findings were published in the early online version of the Journal of Great Lakes Research. “It could make it difficult to get into fields. There’s also a potential for more flooding.””

  6. paulm says:

    There is not much we can do about this now.
    Another great big die off… Anthropogenic – Mass Extinction 6

    brainless frogs…

  7. Lou Grinzo says:


    Thanks very much for highlighting this, especially Carl Zimmer’s excellent piece.

    I’ve been saying for some time that ocean acidification deserves much more attention than it gets, simply because it has such an immense potential for human impacts via the food supply. The truly nasty part of OA (aside from its insanely low profile) is how hard it is to address via geoengineering. All the orbital mirrors and albedo fixes don’t do diddly for this, since they don’t pull CO2 out of the atmosphere and away from the oceans.

    By the way–when are we going to get over this habit of giving really big, scary problems overly scientific and bland names? “Ocean acidification” sounds like a chapter in your high school chemistry book that you ignored. How about “ocean poisoning”?

  8. mike roddy says:

    Horrifying material indeed, but I’m glad that laboratory scientists are working so hard to do the tests and simulations.

    This is going to create feedbacks, too. The ocean currently emits 332 Gt of CO2 and sequesters 338 Gt. Rapid acidification is going to cause impoverishment of the ocean food chain, and there is not going to be enough time for species to adapt and evolve. This is unprecedented, and can’t be simulated or tested very accurately. The likely result will nevertheless be the oceans turning into net sources of CO2, in addition to the starvation of fisheries-dependent human populations.

    I hope this message gets out, since the basic fact of rapid ocean acidification is impossible to dispute, and tech fixes won’t work. I still predict that the deniers will give it their best shot anyway. No doubt they’re looking for a way to burglarize the oceanographers’ emails as I write this.

    I’m glad there are people like Joe and other commenters here who are pissed off about this. We need to think of more and better ways to communicate this knowledge.

  9. MarkB says:

    Sea level continues to climb:

    Tough for deniers to cherry-pick their way out of it, either using short-term trends or a non-smoothed metric. All 4 metrics (inverted barometer applied / not applied, seasonal signal removed / not removed) indicate the same thing.

  10. sam says:

    What exactly is this based on again? Speculation about the past and a computer model? Is this what you guys are trying to throw out there as proof? You want us to restructure our ecomony, transfer billions of dollars to other countries, and drastically change our lifestyle based on this??? What a joke.

  11. mike roddy says:

    Sam, #11,

    If you have a problem with scientists’ results on this topic, I suggest that you quote alternate peer reviewed studies. If you can’t do that, or you do not believe in the scientific method, I don’t really see what you can contribute to this discussion.

  12. Steve Bloom says:

    Joe, this new paper in PNAS is exceptionally bad news that makes for an unfortunate counterpoint to the PETM OA paper:

    Atmospheric CO2 concentrations during ancient greenhouse climates were similar to those predicted for A.D. 2100

    Abstract: “Quantifying atmospheric CO2 concentrations ([CO2]atm) during Earth’s ancient greenhouse episodes is essential for accurately predicting the response of future climate to elevated CO2 levels. Empirical estimates of [CO2]atm during Paleozoic and Mesozoic greenhouse climates are based primarily on the carbon isotope composition of calcium carbonate in fossil soils. We report that greenhouse [CO2]atm have been significantly overestimated because previously assumed soil CO2 concentrations during carbonate formation are too high. More accurate [CO2]atm, resulting from better constraints on soil CO2, indicate that large (1,000s of ppmV) fluctuations in [CO2]atm did not characterize ancient climates and that past greenhouse climates were accompanied by concentrations similar to those projected for A.D. 2100.”

    Is it possible that this would require estimates of the PETM carbon injection to be revised substantially downward? Regardless, these results combined with the recent papers finding relatively low CO2 levels for the warm intervals during the Pliocene and Miocene mean the current 390 ppm is already far into the danger zone, much more so than Hansen et al.’s Target CO2 paper was able to show just two years ago.

  13. Al says:

    Hey Lou, How about a dumping few hundred tankers of Sodium Hydroxide and mixing? (Hee, hee)

  14. Chris Dudley says:


    To clean up what we’ve put into the atmosphere, we need about 30 cm of coral growth over about 15 times the current active area of coral in the oceans. A tall order it would seem although sea level rise should encourage coral growth where it is established for a time before acidification becomes too strong an influence. One possibility to encourage more coral growth would be to illuminate parts of the ocean that are currently too dark for corral to grow rapidly. There are some technologies available now that might be used to do this.

  15. From Peru says:

    Great link, MarkB !

    Now the “Global Cooling” nonsense is definitely over!

    If total(altimetric)SLR IS 3,2 mm/yr…
    And Ocean mass (i.e. land ice melt) SLR is around 2mm/yr…

    Thermo-steric SLR is around 1 mm/yr.

    Given that there is no warming evident in the upper 700 meters of Ocean, the heat must have accumulated below.

    After considering the fact that “The warming required to produce 1 mm SLR if the heat is deposited in the top 700 m of the ocean can take from 50 to 75 *10^20 J, or 110*10^20 J if deposited below 700 m depth”

    Deep Ocean must have accumulated around 110*10^20 J in last decade to explain the thermo-steric SLR trend.

    The “Trenberth’s travesty” is now definitively over.

    NOTE TO READERS: Kevin E Trenberth made a paper (referred fully below) showing his worry for a “missing heat” in last decade: since 2003, the trend in upper ocean 700 meters Ocean Heat Content is nearly flat. If ocean is not warming, then more than 90% of 0,9 W/m^2 of forcing measured by CERES is missing.

    In the “Climategate” e-mail story, there was a mail saying “The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t.” written by Trenberth, that was used by the deniers to claim that He was recognizing that Earth had no warmed in last decade.

    Now is clear that the heat was sequetered below 700 meters, as the Upper ocean heat content(flat trend) and SLR data(themo-steric SLR continuing unabated) show.


    1)Ocean mass sea level rise:”Sea level budget over 2003–2008: A reevaluation from GRACE space gravimetry,satellite altimetry and Argo”, by A. Cazenave et al.

    2)”An imperative for climate change planning: tracking Earth’s global energy”, by Kevin E Trenberth

    See also the article “Understanding Trenberth’s travesty” at Skeptical Science:

  16. George Darroch says:

    If this was the worst the ocean had to face, it would be a disaster. Unfortunately we’re also suffering extreme overfishing of all major fish-stocks, and extensive bottom trawling which destroys corals and other organisms(equivalent to clearfelling a forest to catch a few parrots).

    We’re in for an interesting ride.

  17. Michael T says:

    Check out this article about SLR. Look at the map at the bottom of the page. Notice the green along the west coast. That means little to no change in sea level. But look out toward the Philipines and Indonesian islands. Quite the opposite! Pushing 15-20cm in Sea Level Rise from ’93-’08.

  18. George D says:

    Shorter Sam: I don’t like the science, can you tell me something else?

  19. Leland Palmer says:

    Ocean acidification is another reason we need to put carbon back underground:

    Bio-energy with carbon capture and storage (BECCS) is a greenhouse gas mitigation technology which produces negative carbon emissions by combining biomass use with carbon capture and storage.[1] It was pointed out in the IPCC Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) as a key technology for reaching low carbon dioxide atmospheric concentration targets.[2] The negative emissions that can be produced by BECCS has been estimated by the Royal Society to be equivalent to a 50 to 150 ppm decrease in global atmospheric carbon dioxide concentrations.[3]

    The concept of BECCS is drawn from the integration of biomass processing industries or biomass fuelled power plants with carbon capture and storage. BECCS is a form of bio-energy with carbon storage(BECS). BECS also includes other technologies such as biochar and biomass burial.[1]

    The main appeal of BECCS is in its ability to result in negative emissions of CO2. The capture of carbon dioxide from bioenergy sources effectively removes CO2 from the atmosphere.[4]

    Carbon capture and storage (CCS) technology serves to intercept the release of CO2 into the atmosphere and redirect it into geological storage locations.

    The amount of CO2 that has been released to date is believed to be too much to be able to be absorbed by conventional sinks such as trees and soil in order to reach low emission targets.[9] In addition to the presently accumulated emissions, there will be significant additional emissions during this century, even in the most ambitious low-emission scenarios. BECCS has therefore been suggested as a technology to reverse the emission trend and create a global system of net negative emissions.[2][9][10][11][12] This implies that the emissions would not only be zero, but negative, so that not only the emissions, but the absolute amount of CO2 in the atmosphere would be reduced.

    We should nationalize the coal fired power plants, and forcibly convert them to BECCS.

    Most coal fired power plants are located on rivers or other bodies of water, for cooling water. These rivers constitute natural transport networks to bring biomass or compressed charcoal from anywhere on the watershed upstream of the coal fired power plant.

    By adding a gas turbine combined cycle to these BECCS power plants, we could raise efficiency high enough to pay for the energy cost of carbon capture and compression for underground storage. The Clinton era HIPPS (High Performance Power System) idea was similar, but involved a high temperature heat exchanger to produce heated air to run the gas turbine on.

    Efficiency by the Numbers:

    Which, in my view, is what gas turbines are. No other technology currently available or likely to be deployed in the next decade has the potential to obtain so much power from so little energy. In a future where fuel supplies are likely to be constrained (due to geological, climatological, political, or economic factors) the inherent efficiency of the gas turbine will not be overlooked.

    …But while that heat cannot be used by the first machine, it can be used to provide energy input to another engine, provided that the temperature of the rejected heat is high enough for the “bottoming” engine to produce more work, and in turn, reject heat as required by the Second Law. Two engines working together in this way are in what has become known as a “combined cycle.”

    In the case of modern Brayton cycle gas turbine, its Qout (typically at 1,000 oF (538 oC) is sufficient to produce steam to run a Rankine cycle steam turbine to generate more electrical power.

    A reasonable value for a Rankine cycle operating at typical CC conditions would be 30 percent. The sum of those two individual efficiencies minus their product becomes:

    hcc= 0.40 + 0.30 – (0.40)(0.30) = 58 percent.

    The efficiency of the two turbines working in combined cycle is, in fact, greater than either of the two heat engines working separately.

    One form of carbon capture- oxy-fuel combustion- could help raise combustion temperatures and heat transfer sufficiently that no natural gas combustion to raise inlet temperatures to the 1500 C inlet temperature of the gas turbine would be necessary.

    Deep saline aquifers contain enough storage capacity for several trillion tons of CO2.

    We need to seize the coal fired power plants, and transform them into BECCS. We need to start putting a billion tons of carbon per year back underground, here in the U.S.

    China needs to do the same, and put a billion tons of carbon per year back underground, too.

    No matter what the cost, and no matter if there is some CO2 leakage from the deep saline deposits, it has to be better than what awaits us if we continue on as we are.

    And actually, cost is mostly about thermal efficiency. These BECCS plants would be maybe 1.5 times as efficient as existing coal plants, allowing for parasitic losses from the CCS.

    The extra efficiency could pay for the conversion, I think.

  20. Stuart says:

    Lou Grinzo @ 8 – how about “ocean collapse”?

  21. From Peru says:

    Chris Dudeley #15:

    Stimulating coral growth to capture CO2 is counter-producent.

    Calcification is the following reaction:

    2HCO3-(ac)+ Ca++(ac) = CaCO3(s)+CO2(ac)+H20(l)

    So it RELEASE CO2, not fixes it.

    From the formula is clear how CO2 dissolves the carbonate shells: add CO2 and CaCO3(s) will turn into HCO3-(ac) to compensate.

  22. john atcheson says:

    Re #11

    Pssst Sam,don’t look now,but your ignorance is showing If you’d like to debate, then marshal arguments based on facts, don’t make vague snide assertions without foundation. In the meantime, consider this:

    1) Restructuring our economy will be an economic boon and it will result in less money going overseas, not more — oil remains the single biggest source of our trade deficit. So your assumptions of economic Armageddon are simply wrong.

    2) The oceans have already acidified, warmed, and increased in volume, so it’s not just “models and geologic history” although if you knew anything about science that would be sufficient reason to act in the face of potential cataclysmic events.

    3)The value of fish catch alone is half a trillion dollars — losing that would result in lost income of $5 trillion every decade in perpetuity.

    So as you can see, your little post does more to demonstrate your own abysmal lack of knowledge than it does to discredit the science you so clearly do not understand. Spouting denier talking points while in a state of blissful ignorance is not an acceptable response to the crisis we face.

  23. lee karkruff says:

    the best, clearest,least denier influenced (no name calling, ftmp, and no coherent or realistic rebuttal) and most frightening explanation of OA I’ve yet to read-thank you all, will try to do what I can (?) yeesh——- Lee

  24. lee karkruff says:

    p.s. but I also have to say, cap&trade is NOT the answer-thanx for the forum, from a science oriented woodworker, Lee

  25. Mike Kenny says:

    To be precise and correctly stated CO2 will cause the oceans to be less Alkaline. When the vernacular of more acidic is used it is intended to sensationalize and make scary this process that has been cyclical in nature for millennium.

  26. Sean says:

    So Mike, you’re saying we’re debasing the oceans?