How Gaia and coral reefs regulate ocean pH

by Jim Steele

Although some researchers have raised concerns about possible negative effects of rising CO2 on ocean surface pH, there are several lines of evidence demonstrating marine ecosystems are far more sensitive to fluxes of carbon dioxide from ocean depths and the biosphere’s response than from invasions of atmospheric CO2. There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015). On the contrary, rising CO2 makes photosynthesis less costly.

Furthermore in contrast to researchers arguing rising atmospheric CO2 will inhibit calcification, increased photosynthesis not only increases calcification, paradoxically the process of calcification produces CO2 and drops pH to levels lower than predicted by climate change models. A combination of warmer tropical waters and coral reef biology results in out-gassing of CO2 from the ocean to the atmosphere, making coral reefs relatively insensitive to the effects of atmospheric CO2 on ocean pH.

Sixty million years ago proxy evidence indicates ocean surface pH hovered around 7.4. If surface pH was in equilibrium with the atmosphere, then CO2 concentrations would have hovered around 2000 ppm, but there is no consensus that CO2 reached those levels. However as will be discussed, there are biological processes that do lower surface pH to that extent, despite much lower atmospheric CO2 concentrations.

Over the next 40 million years corresponding with the rearrangement of the continents and ocean currents, the formation of the Antarctic Circumpolar Current and initiation of Antarctic glaciers, the evolutionary expansion of diatoms and their increasing abundance (diatoms are the most efficient algae for exporting carbon to ocean depths), ocean carbonate chemistry was greatly altered. As a result ocean surface pH gradually rose above pH 8. Then for our last 20 million years, ocean surface pH has fluctuated within this new equilibrium between 8.4 and 8.1, as seen in Figure 1 below (Pearson and Palmer 2000). For the past 400,000 years, pH rose to about 8.35 during the depths of each ice age. Then during each warm interglacial period, when both land and marine productivity increased, pH fell to ~8.1 (Honisch 2005).slide1Although it is commonly assumed atmospheric CO2 and ocean surface pH are in equilibrium, studies examining various time frames from daily and seasonal pH fluctuations (Kline 2015) to the millennial scale transitions from the last ice age to our warm interglacial (Martinez-Boti 2015), demonstrate surface ocean pH has rarely been in chemical equilibrium with atmospheric CO2. Because oceans contain over 50 times as much CO2 as the atmosphere, surface pH is more sensitive to changes in the rates of upwelling of low-pH, carbon-rich deep waters. It is the response of photosynthesizing organisms and the food webs they support that largely determines how much carbon is sequestered in the surface layers and then sent to deeper waters (the biological pump).

As discussed in an earlier essay, the “biological pump” modulates how much CO2 is sequestered and how much CO2 will out-gas to the atmosphere. It has been estimated that without the biological pump, pre-industrial atmospheric CO2 would have out gassed and raised atmospheric CO2 to 500 ppm, instead of the observed 280 ppm. Ironically the processes that build coral reefs also increase surface CO2 concentrations and lower regional pH to levels lower than expected by equilibrium with atmospheric CO2. This biological control of the earth’s chemistry is the essence of Gaia theory.

Gaia theory stimulated great scientific interest (as well as controversy) since the 1970s, and stimulated more extensive investigations into how the biosphere affects the earth’s chemistry. Gaia’s founding scientist James Lovelock formulated Gaia theory while working for NASA seeking chemical signatures of life on other planets. For example, due to living organisms our atmosphere maintains about a 21% concentration of oxygen. Without photosynthesizing organisms, the atmosphere would contain extremely low amounts of oxygen. Thus Lovelock argued, “if life has merely a passive role in cycling the gases of the air, then the concentrations will be set by equilibrium chemistry; in fact they most certainly are not.” Shedding the mystical connotations that many “New Age” adherents attributed to Gaia, several universities have now created departments studying Gaia’s effects, but under less anthropomorphic titles such as Earth System Sciences or Biogeochemistry.

Unfortunately Gaia is often misrepresented as a conscious super-being deserving of religious devotion, with some adherents even advocating Gaia should replace the earth’s major religions. Gaia’s deification was resented both in established religious circles, and by Gaia’s scientific proponents like Dr. Lynn Margulis. She stressed Gaia is simply “an emergent property of interactions among organisms”. Or as one of her graduate students suggested, Gaia is simply “symbiosis as seen from space”.

Gaia theory also weighed in on climate change debates and was advocated by Al Gore and climate scientists such as Stephen Schneider. While basic Gaia theory simply argues a variety of biological interactions provide negative feedbacks from which a degree of self-regulating homeostasis emerges, those with a more alarmist view of the earth’s changing climate argued those self regulating processes had been pushed to a disastrous tipping point by rising CO2. In contrast climate skeptics like world-renowned physicist Freeman Dyson also embraced the concepts of Gaia as a “great force for good” uniting people to save natural habitat and endangered species. But Dyson also bemoaned, “I am horrified to see the environmental movement hijacked by a bunch of climate fanatics, who have captured the attention of the public with scare stories.”

Despite Lovelock’s belief that life regulates earth’s chemistry via a variety of negative feedbacks, his logic was at first swayed by those CO2 scare stories. In a more fearful state of mind Lovelock published books like “The Revenge of Gaia” and in newspaper interviews predicted fast-approaching, global-warming doom stating, “Billions of us will die” and only the “few breeding pairs of people that survive will be in the Arctic”.

More recently however Lovelock recanted stating,I was ‘alarmist’ about climate change & so was Gore!” ‘The problem is we don’t know what the climate is doing. We thought we knew 20 years ago”.

Putting politics and religion aside, the Gaia perspective provides a valuable framework that incorporates the biosphere as a critical active player in global climate and chemical cycles. And only from that framework can we fully account for oscillations in the oceans’ pH on daily, annual, decadal and millennial timeframes.

pH in a Lifeless World

Global climate models, such as used by Caldeira and Wickett 2005, estimated that ocean pH has dropped by (0.09 pH) from 8.2 to ~ 8.1 since preindustrial times due to rising anthropogenic carbon dioxide emissions. They then predicted a further pH drop of 0.3 to 0.4 by 2100 as emissions increase. This claim has been cut and pasted into nearly every journal article that hypothesizes an impending catastrophe driven by “ocean acidification”. However an average pH of 8.1 is typical for interglacial periods such as the one we are now experiencing. But more importantly Caldeira and Wickett’s modeling experiments only examined geochemical processes and erroneously assumed 1) ocean surface CO2 is in equilibrium with the atmosphere; and 2) the biosphere was a neutral participant. Caldeira’s model was based on their non-Gaia assumption that ocean surface pH is “affected only by air-sea fluxes and directly injected carbon.” Indeed, if sequestration of CO2 by photosynthesis is immediately offset by the release of CO2 in the surface layers via respiration, then such an assumption may hold some validity. However that is never the case. And according to the IPCC if there were no biological pump transporting carbon to the ocean depths, oceans would now be experiencing an 8.0 pH.

slide2As seen in the graph above from Cohen and Happer models that suggest ocean pH should have declined over the past 150 years as atmospheric CO2 concentrations rose are supported by an abiotic chemical analysis. Modulated by ocean alkalinity, at 400 ppm atmospheric CO2, surface seawater declines to pH 8.2 or 8.1 (blue curve). For un-buffered rainwater (or river outflows without buffering) pH drops to 5.5 (red dashed curve). However even without any modulating biological effects, the graph suggests a degree of chemical homeostasis where increasing CO2 concentrations have an increasingly smaller effect on ocean pH. For example when CO2 concentrations increase from 0 to 100 ppm, pH rapidly drops from over 11.0 to 8.7. In contrast a quadrupling of atmospheric CO2 since pre-industrial times (~250 to 1000 ppm) would only lower ocean surface pH from 8.3 to 7.9 (blue curve). Counter-intuitively the different dissolved CO2 species exert strong buffering effects. Furthermore far from being catastrophic, not only is a pH range between 8.4 and 7.7 experienced daily in thriving coral reefs, that range appears to be an optimal balance that supports both photosynthesis and calcification!

Extreme views by researchers like Hoegh-Guldberg (2014) have speculated 95% of the coral will be lost by 2050, and he argues our current high levels of CO2 are creating conditions coral have not experienced for millions of years. Yet in terms of pH (and temperature) such “scientific” claims are pure nonsense. First a modeled average surface pH tells us very little about the pH that directly affects marine organisms locally. Due to the counteracting effects of photosynthesis, respiration and calcification, coral reefs can experience a pH hovering around 8.5 or higher during the day followed by a low pH of 7.8 or lower at night. Kline 2015 acknowledged, “As with many other reefs, the nighttime pH minima on the reef flat were far lower than pH values predicted for the open ocean by 2100.” Elsewhere researchers concluded that in addition to atmospheric pH, the complex interactions controlling pH especially in coastal zones, make detection of any trends towards acidification “not trivial and the attribution of these changes to anthropogenic CO2 emissions is even more problematic.” (Duarte 2013)

Why More Acidic Conditions Benefit Photosynthesis

Shallow-water reef-building corals are able to thrive in low-nutrient tropical waters via their symbiosis with a genus of photosynthesizing algae (discussed here.) In order to sustain photosynthesis, corals actively pump hydrogen ions (H+) into the vesicles encapsulating their algal symbionts. This lowers its internal pH to truly acidic levels between pH 4 and 5 (Barott 2015). This increases H+ concentrations up to 10,000 times greater than any theoretical contributions to surface waters by atmospheric CO2. If coral do not acidify their symbionts’ surroundings, the limiting supply of CO2 would dramatically decrease the rate of photosynthesis.

Why does an acidic environment benefit photosynthesis?

To understand the benefits of corals’ purposeful acidification, we must first review how CO2 reacts when dissolved in water. Dissolved CO2 can take 3 forms (or “species”) collectively referred to as Dissolved Inorganic Carbon (henceforth DIC):

1) Carbonic acid (H2CO3),

2) Bicarbonate ion (HCO3) after losing one H+

3) Carbonate ion (CO3-2) after losing a second H+ .

When CO2 first dissolves, a small proportion bonds to water molecules and forms a weak carbonic acid (H2CO3). But the bond is weak causing carbonic acid to convert back and forth with its CO2 form so rapidly, most researchers treat these two forms as the same chemical species. Carbonic acid is a weak acid, and weak acids are critical buffering agents for most living organisms precisely because its species can rapidly and reversibly change form. Carbonic acid and phosphoric acid are the 2 most critical buffering agents for maintaining a narrow pH range in humans and other animals. In the form of carbonic acid, water’s 2 H+ ions can more easily detach to form bicarbonate and carbonate ions when pH rises. Buffering happens because those added H+ ions counteract a rising pH. (Higher pH means lower H+ concentrations.) Conversely when pH falls (Lower pH means higher H+ concentrations), the excess H+ ions recombine with and are sequestered by any existing carbonate and bicarbonate ions to counteract the falling pH.

Figure 2 illustrates how changes in pH alter the species composition of DIC. For example during photosynthesis CO2 is consumed causing pH to rise. Between pH 7.0 and 8.6, over 90% of the dissolved CO2 naturally converts to bicarbonate ions (HCO3). But bicarbonate ions cannot be directly used in photosynthesis. Photosynthesizing organisms can only use CO2. Thus if photosynthesis drives pH to 8.2 or higher, the requisite CO2 species approach zero. In addition to competing for a dwindling supply of CO2, photosynthesis consumes the limited supplies of nutrients. Thus photosynthesis creates negative feedbacks that inhibit additional photosynthesis.

slide3To overcome the limiting supply of CO2, organisms like coral concentrate bicarbonate ions in compartments into which they pump H+ ions and lower the pH. As seen in Figure 2, at pH 5 or lower, 90% of the DIC converts to CO2. Once bicarbonate ions are imported and concentrated, the conversion to CO2 is also accelerated by the ubiquitous enzyme carbonic anhydrase. However bicarbonate ions cannot simply diffuse into a cell or pass through internal membranes. The ions must be pumped. However pumping and concentrating those ions requires transporters and an expenditure of energy. In contrast whenever surrounding waters experience a lower pH, it makes CO2 more available so that the energy expenditures drop because CO2 freely diffuses into cells and through membranes.

The same carbonate chemistry reactions that provide more CO2 for photosynthesis also explain how some pharmaceutical antacids work and how DIC buffers ocean pH. Bicarbonate is a common ingredient in antacids like Alka-seltzer. When H+ ions increase due to acid indigestion, ingested bicarbonate ions rapidly bond to H+ to form CO2 gas, which can then be carried away by the blood or by a good belch. Likewise when ocean concentrations of H+ ions increase, they more readily bond to the bicarbonate and carbonate ions to minimize the drop in pH and form more CO2, which can be quickly utilized during photosynthesis.

However below pH 7.0, nearly all carbonate ions (CO3-2) will be converted to bicarbonate (HCO3), so that carbonate ions no longer serve as buffering agents. (CO3-2 + H+ forms HCO3). However in coral reefs, that loss of buffering capacity at lower pH is counteracted to a degree by increased dissolution of calcium carbonate minerals. Dissolution of calcium carbonates counter-intuitively absorbs CO2 and releases carbonate ions to increase the water’s buffering capacity, thus exerting a negative feedback that tries to raise pH (Morse 2007). Nonetheless the concept that a lower pH reduces the concentration of carbonate ions evoked climate fears amongst some researchers who incorrectly believed calcifying organisms require carbonate ions. But research shows no such requirement. All calcifiers use the more abundant bicarbonate ions and bicarbonate ions will be plentiful even if pH unrealistically fell to 6.0

Outside of coral reefs, other marine ecosystems also benefit from lower pH. For example diatoms now account for 40% of the world’s ocean primary productivity and flourish in upwelling waters that bring abundant CO2 and DIC from the ocean’s dark depths into sunlit surface regions. Although this upwelling deceases surface pH and provides more CO2, diatoms still rely on bicarbonate transporters and carbonic anhydrase to ensure an adequate supply of CO2 for photosynthesis. Hopkinson et al. (2011) calculated a doubling of ambient CO2 levels would save diatoms ~20% of the energy they expended on importing bicarbonates. Globally different photosynthesizing organisms have demonstrated a variety of responses to rising CO2 but altogether there appears to be few negative effects on photosynthesis due to elevated CO2 and depending on the species small to large benefits (Mackey 2015).

The Omega Myth

In a lifeless ocean when carbonate ions rise to a certain concentration, they react with ever-present calcium ions to form calcium carbonate minerals like aragonite and calcite. Those minerals are used to make shells, skeletons and reefs. If carbonate ion concentrations are lower, calcium carbonate minerals are more likely to dissolve. When there is a balance between formation and dissolution of those minerals, the water is said to be saturated with respect to that mineral, and saturation is represented by the omega symbol (W). The oceans are currently oversaturated with respect to calcium carbonate minerals, but some researchers became fearful that a falling pH could lower the supply of carbonate ions, and eventually drive the ocean’s saturation point so low that calcium carbonate minerals will dissolve faster than they form. However biologically controlled calcification reveals that simple metrics of chemical equilibriums and saturation points do not accurately demonstrate the biologically controlled calcification process. In that regard several researchers have now published evidence demonstrating the “Omega Myth”.

First biologically controlled calcification does NOT depend on, or directly utilize seawater carbonate ions. Nor does calcification depend on observed saturation states of the oceans (Maranon 2016). Transporters are required for carbonate ions to cross any membrane, but no carbonate transporters have ever been detected. Instead, as with photosynthesis, calcifiers actively uptake the more abundant bicarbonate ions and concentrate them in compartments. Most calcifying organisms have evolved mechanisms to “up-regulate” their internal pH by pumping H+ ions out of the compartment and raising internal pH. In addition pumping H+ ions out of the calcifying compartments is beneficial because it maintains an electrical gradient that facilitates importing calcium ions (Ca++) into the calcifying compartment. With a higher internal pH, bicarbonate sheds an H+ and converts into carbonate ions and when concentrated in the presence of concentrated Ca++, calcium carbonate minerals readily form.

Although in some species photosynthesis and calcification compete for bicarbonate ions, photosynthesis generally benefits calcification by providing energy, and by raising external pH, which lowers the cost of pumping internal H+ ions to the surrounding waters. In addition on a per molecule basis, the cost of calcification requires less than 1% of the energy produced by photosynthesis (McCulloch 2012). Accordingly numerous studies have reported that greater rates of photosynthesis correlate with greater rates of calcification. The same holds true for other calcifying organisms. For example across the tropical ocean, the ratio of net calcification to net photosynthesis for coccolithophores remained constant despite regions of widely varying surface pH and calcite saturation levels (Maranon 2016).

Past hypotheses arguing calcification was dependent on carbonate ion concentration, or aragonite and calcite saturation levels, were most likely misled by the fact that higher carbonate ion concentrations are a daily “side effect” of photosynthesis. It is the rate of photosynthesis and the energy it provides that typically controls calcification rates. And as reported in the discussion on the coral adaptive bleaching hypothesis, coral are always shifting and shuffling their symbionts to maximize photosynthesis to best adapt to changing local microclimates. The bigger threat to coral photosynthesis is heavy sediment loads from disturbed landscapes that can block the sun and suffocate polyps.

How Calcification Lowers pH more than Atmospheric CO2

Strangely enough, although some researchers fret higher CO2 concentrations will reduce calcification, it is the very process of calcification that results in the “alkalinity pump.” Calcification removes buffering bicarbonate and carbonate ions from the surface and pumps them to the deep. Calcification also releases CO2 in the surface waters and in combination with less buffering capacity, lowers pH to a much greater extent than possible by surface exchanges with rising atmospheric CO2.

Assuming the modeled background pH of 8.1, and if all else is equal, we would expect pH to rise during the day due to photosynthesis and then fall back to pH 8.1 at night due to respiration. As seen in the graph below for daily (diel) pH values on Heron Island in the Great Barrier Reef (from Kline 2015), coral reefs rarely spend any time at Caldeira’s modeled pH value of 8.1. When photosynthesis and carbonate dissolution outweigh respiration and calcification, surface pH can rise to 8.4 or higher as would be expected. Furthermore when surface pH is above 8.1, the concentration of surface CO2 is lower than atmospheric CO2, and this difference allows CO2 to diffuse into the ocean. However any absorbed CO2 is quickly sequestered into organic molecules via photosynthesis during which surface pH remains high and never comes into equilibrium with atmospheric CO2 during the day.

slide4Conversely without photosynthesis, nighttime respiration and calcification increase surface CO2 concentrations and lower pH. Reefs benefit because those processes replenish the depleted CO2 required for photosynthesis on the following day. Furthermore if more organic molecules are formed and sequestered than subsequently respired, we would expect surface pH to remain above 8.1. Indeed photosynthesis produces a large reservoir of dissolved and particulate organic molecules that may persist for decades, centuries, and millennia. When those stored molecules eventually return to the surface, pH can be lowered due to respiration of ancient carbon, independent of atmospheric CO2. Other organic molecules are also formed that resist decomposition for millions of years. And molecules like DMS are out-gassed to the atmosphere where they serve as cloud condensation nuclei and inhibit further warming of ocean surface temperatures.

Thus due to long-term sequestration of CO2 that exceeds respiration we would expect surface pH to remain above 8.1 for the short term. However due to the release of CO2 during calcification, reef pH drops far below 8.1. Calcification infuses the surface waters with an excess of CO2 largely driving the nighttime pH down as low as 7.7. Furthermore at a pH below 8.1, CO2 concentrations in the ocean’s surface rise higher than the atmosphere’s, and this results in nighttime out-gassing of CO2. Instead of CO2 invading the ocean and affecting coral, overall measurements show coral reefs are net sources of CO2 from the ocean to the atmosphere. Similar dynamics from calcifying coccolithophores likewise promotes CO2 fluxes from the open ocean, and inhibits uptake from the atmosphere. Again as Gaia predicts, biological processes control carbonate chemistry and when or where atmospheric CO2 enters or leaves the ocean.

Although studies in the waters around Hawaii (Dore 2009) reported an increasing trend in DIC that was “indistinguishable” from what rising atmospheric CO2 predicts researchers observed, “Air-sea CO2 fluxes, while variable, did not appear to exert an influence on surface pH variability. For example, low fluxes of CO2 into the sea from 1998–2002 corresponded with low pH and relatively high fluxes during 2003–2005 were coincident with high pH; the opposite pattern would be expected if variability in the atmospheric CO2 invasion was the primary driver of anomalous DIC accumulation. However that observed pattern is exactly what we would expect to arise from biological effects.

Furthermore oscillating decadal trends in wind strength can further magnify biological effects causing pH to trend independently of atmospheric CO2. CO2 generated by calcification does not completely outgas and thus changes in the rate at which reefs are flushed with open ocean water will modulate how calcification affects surface pH. In contrast to Caldeira’s “lifeless” pH models that suggest pH has dropped from 8.2 to 8.1 since preindustrial times, a study of pH since 1700 AD on Flinder’s Reef in the Great Barrier Reef concluded pH has oscillated between 8.15 and 7.9 every 50 years. During a positive Pacific Decadal Oscillation and El Nino years, trade winds slowed and reduced the flushing rate of the reef. As a result there was a build up of CO2 released from calcification and average pH dropped pH to 7.9. When winds increased during a negative PDO and more La Ninas, the reef was flushed and pH rose to 8.15. Several studies have linked changes in pH driven with multidecadal oscillations.

For example examining surface pH in the Sargasso Sea Goodkin 2015 reported, “from 1950 to 1996, when surface ocean pHs are predicted to decline more rapidly due to anthropogenic CO2 emissions, pH at Bermuda increases in response to a declining AMO.” They concluded, “ocean pH does not simply reflect atmospheric CO2 trends but rather that circulation/biogeochemical changes account for >90% of pH variability in the Sargasso Sea and more variability in the last century than would be predicted from anthropogenic uptake of CO2 alone.”

Similarly Yeakel 2016 reported Bermuda reefs experienced a drop in pH in association with a negative NAO that caused westerly winds to move further south and generate a deeper winter mixed layer just to the north of the Bermuda reefs. Deeper mixing brought more DIC to the surface layers and promoted greater plankton blooms. The resulting organic particles and zooplankton that fed on the blooms, then circulated over the Bermuda reef. The resulting increase in respiration and calcification caused an “acidification event”.

Thus to reliably distinguish multidecadal trends in pH driven by ocean oscillations, upwelling and deeper surface mixing versus trends due to rising atmospheric CO2, it will require 60 to 100 years of observation; far longer than any data series to date.

Ocean Surface pH is More Sensitive to Ventilated CO2 Stored at Ocean Depths

Published estimates of anthropogenic CO2 now stored in the upper ocean layers and affecting pH has been based on “the assumption that ocean circulation and the biological pump have operated in a steady state since preindustrial times” (Sabine 2010). The problem is such assumptions are faulty and misleading. The biological pump and ocean circulation are not in a steady state. Regional upwelling has increased since the Little Ice Age (Gutiérrez 2009) and during the past 3 decades (Varela 2015). Multidecadal changes in hurricane frequency and intensity affect upwelling. Changes in surface winds due to El Nino and La Nina, the North Atlantic Oscillation and Pacific Decadal Oscillation affect upwelling (Ishii 2002). Coastal and equatorial upwelling bring an enormous amount of DIC to the surface, with subsequent transport to the gyres of the open ocean, causing declines in open ocean surface pH at rates that are much faster than possibly attributed to atmospheric diffusion.

While 50% of the sequestered carbon formed during photosynthesis is respired before sinking into the dark depths, a tremendous pool of dissolved organic carbon has been created that may not be respired for decades, centuries or millennia and slowly contributes to the pool of DIC at various depths and locations (Giorgiou 2002). This further complicates any attribution of trends in surface pH. For example upwelling of stored CO2 is believed to have been the main driver of the rise in atmospheric CO2 and the fall in ocean surface pH during the transition from the glacial maximum to our interglacial.

As discussed in the article on natural cycles of ocean “acidification”, and illustrated in the graph below by Martinez-Boti, over the past 15,000 years proxy data (thick lines) has determined surface pH has rarely been in equilibrium with expectations (green line) based on models driven by atmospheric CO2. As illustrated, surface pH was more sensitive to the upwelling of subsurface DIC. The venting of stored carbon led to a drop in average regional pH from the 8.3 during glacial times to a pH fluctuating between 8.1 and 8.2 during our current interglacial.slide5The mechanisms that lowered surface pH to 8.3-8.4 during the Last Ice Age is a matter of considerable debate, but clearly more carbon was being sequestered at depth and less carbon was being pumped to the surface. Several authors have reported less upwelling during the Ice Age. While colder temperatures and less upwelling would reduce rates of photosynthesis, colder temperatures also reduce rates of respiration and calcification. A lower rate of respiration would allow more organic carbon to sink to deeper depths before being completely consumed. Sinking to deeper depths prevents a quick return to the surface during winter mixing or mild upwelling.

It has also been speculated that the loss of coral reefs during the last Ice Age contributed to the higher pH. Research has estimated that during the cold nadir of each ice age, coral reef extent was reduced by 80% and carbonate production was reduced by 73% relative to today. Lower calcification rates would reduce the alkalinity pump, reduce surface CO2 and increase the buffering capacity of surface waters. Conversely the growth of coral reefs as the earth warmed and sea levels rose would contribute to rising CO2 concentrations and falling pH. Vecsei 2004 concluded, “The pattern of reef growth that emerges suggests that emission of CO2 resulting from carbonate production was important particularly during the late stages of deglaciation.”

Overall observations of the effects of photosynthesis and calcification reveal coral reefs are not victims of a fall of pH from 8.2 to 8.1 pH as suggested by Caldeira and Wickett 2005, Doney 2009 or Hoegh-Guldberg (2014). On the contrary as Gaia theory would suggest, coral reefs are actively regulating surface pH.

Biosketch: Jim Steele is Director emeritus of Sierra Nevada Field Campus, San Francisco State University and author of Landscapes & Cycles: An Environmentalist’s Journey to Climate Skepticism

Moderation note:  As with all guest posts, please keep your comments civil and relevant.

160 responses to “How Gaia and coral reefs regulate ocean pH

  1. Pingback: How Gaia and coral reefs regulate ocean pH – Enjeux énergies et environnement

  2. If you’re serious about any of this, then you should write a scientific paper (or two). Your claims will not get an adequate review here, nor will they be noticed by the scientific community.

    • Chris Schoneveld

      Not quite true. I just sent this link to Hoegh-Guldberg. He will certainly read it.

    • Steve Mosher, there is a vast difference between internet snipers and editors. Peer reviewed papers often have a link to gray literature. Scientists and editors debate the arguments, snipers attack the arguer. If you have a problem with the graph I supplied from Cohen and Happer (well established scientists) , then demonstrate what was wrong with the graph and supply your evidence. Otherwise you are sniping and the taking the low road.

      I linked to Mackey 2015, which is a review paper, and your dishonest accusation that I misrepresented the paper says more about your sniping tactics. Here are several quotes from the paper that supports my statement “There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015)”

      _ Photosynthesis in Prochlorococcus was unresponsive to pCO2

      _Elevated CO2 caused higher phycobilin and chlorophyll-a content in Synechococcus, leading to a higher
      light harvesting efficiency (α) and a lower light saturation constant (Ek). High CO2 alone did not increase maximal photosynthetic rates in this strain; however, when high CO2 was combined with a warmer temperature (4°C above the control), maximal photosynthetic rates increased twofold relative to elevated temperature alone.

      _At least one genus of picoeukaryotes (Ostreococcus) appears to be strongly enhanced by elevated CO2, with growth rates almost doubling at 1,000 ppm (Schaum et al., 2013).

      _(Regards diazotrophic/ nitrogen fixing plankton) To date, almost all studies suggest that N2 fixation will increase in response to enhanced CO2

      _T. pseudonana [a diatom] showed an increased maximum photosynthetic rate (Pmax) and an increased PE curve halfsaturation constant (Ek) under high CO2, suggesting that more light was required to saturate photosynthesis (Sobrino et al., 2008). Growth rate also increased by 20% under high CO2 in this experiment

      _Under enhanced CO2, Phaeodactylum [diatom} shows increased photosynthetic electron transport rates, but no change or very modest increases in growth
      or C fixation

      _A mesocosm experiment conducted in Bergen, Norway, reported that net community carbon consumption and net photosynthesis increased under increased CO2 for a mixed community of diatoms and coccolithophores (Riebesell et al., 2004). In a later mesocosm study with a different initial community composition, diatoms were outcompeted at high CO2 while picoplankton were strongly stimulated (Riebesell et al., 2013). A third mesocosm experiment with two different diatom species (Skeletonema costatum and Nitzschia spp.) under nutrient replete conditions showed that only S. costatum increased growth rate under enhanced CO2 (Kim et al., 2006). Therefore, the effect of enhanced CO2 on natural diatom populations depends on the species of diatoms, as well as on the overall composition of the phytoplankton community.

      _Coccolithophores appear to rely primarily on aqueous CO2 for photosynthesis, while preferring to access HCO3 – for calcification (Buitenhuis et al., 1999; Bach et al., 2013). Consequently, rising CO2 tends to promote photosynthesis over calcification and reduce the ratio of inorganic to organic carbon in these organisms

      _found that photosynthesis and growth in most species were not C saturated under present-day CO2 concentrations. Because C3 photosynthesis is more sensitive to the direct effects of CO2 concentration, future increases in CO2 will most likely increase photosynthetic rates and growth in marine macrophytes,

      • Mosher and Willard have dishonestly try to suggest the Mackey paper was misrepresented and have repeatedly posted that Mackey reported, ““the photosynthetic benefits of high CO2 are minor” or that “clear trends in the photosynthetic responses of phytoplankton to elevated CO2 have not emerged, and the positive effects, if any, are small“.

        But that is exactly what we would expect from gaia theory. Negative feedbacks generate a level of homeostasis, so that only minor (but beneficial) changes will observed in response to rising CO2.
        Mosher and Willard have butchered the importance of the Mackey paper, which goes into great detail about CCMs, carbon concentrating mechanisms. Some photosynthesizers will up regulate their CCMs to concentrate bicarbonate ions. When their is an increased amount of CO2 due to upwelling or the effects of lower pH on carbonate chemistry, those CCM’s are downregulated as CO2 is more available. Mackey suggests this will save energy as less bicarbonate ions need to be pumped as explained in the essay. The negative feedbacks maintain a homeostasis, and thus we would expect only minor changes in photosynthesis.

        Its funny that Mosher and Willard fail to see the quotes they use for sniping actually support everything stated in the essay.

    • Ooops the above reply should have been a reply to Steve Mosher below.

      • This one is to you Jim… When you mentioned “Over the next 40 million years corresponding with the rearrangement of the continents and ocean currents, the formation of the Antarctic Circumpolar Current and initiation of Antarctic glaciers, the evolutionary expansion of diatoms and their increasing abundance (diatoms are the most efficient algae for exporting carbon to ocean depths), ocean carbonate chemistry was greatly altered.”

        Is there any evidence of Circumference Change? I understand that the time frame is just a drop in the bucket but today science is very good with numbers.

      • Arch, I am not sure what you mean by circumference change. If the shape of the earth is the question I am not sure how we could measure that, and if so what effect it might have other than affecting rotational speed and the Coriolis effect.

      • If the continents have spread the Atlantic, from Scotland to Nova Scotia, (based on observations of a rock outcrop that were at one time connected) it would sure make sense. An expanding surface area should effect the weather patterns for many different reasons.

        I may be wrong on the two locations but I am doing this from memory…

      • AK, I think there must be something wrong with the picture, everything moves but the two dimensional map stays the same size.

      • I think there must be something wrong with the picture, everything moves but the two dimensional map stays the same size.

        You’re joking?

        Just in case you’re not, current plate tectonic theory posits that continental crustal masses move around on an Earth that stays the same size.

      • AK, If the Core of the Earth, is slowly heating the entire planet enough to continue to produce events like earthquakes and the Mid-Atlantic-Ridge, this must increase the surface area of our planet. I can’t explain what force could produce this pressure that constantly pushes outward that would not increase our planets size, other than heat? So, why is the Core, getting hotter & hotter, all these many years after creation?

      • AK, If the Core of the Earth, is slowly heating the entire planet enough to continue to produce events like earthquakes and the Mid-Atlantic-Ridge, this must increase the surface area of our planet.

        You could try following the second link I gave. Basically new crust is created at mid-ocean ridges, and crust is destroyed at subduction trenches. It’s driven by an equilibrium heat flow powered by radiative decay and tidal friction (in the current paradigm)..

        No change in size needed.

      • I was never able to get the toothpaste back into the tube.

      • Arch Stanton,

        Maybe you are slightly confused about the core slowly heating the whole planet.

        The core is slowly cooling. It doesn’t even produce enough energy to maintain surface temperature, let alone to heat it (as in increase its temperature).

        After four and a half billion years or so, most of the shorter half life radioactive elements will have dropped to much lower levels, having converted mass to energy along the way.

        As to the size of the Earth, if solidified rock occupies less volume per unit mass (and generally rock contracts as it cools), then the Earth is shrinking. The slowly congealing and contracting crust exerts tremendous forces on the still molten interior.

        This might well explain such features as the continuous oozing of the still molten interior through the mid ocean ridges which encircle the Earth. Maybe even the wrinkly surface of the Earth, to a degrees, as some parts of the crust contract more than others due to variation in crustal composition.

        Throw in a few magma plumes, and continents might well skate around, bob up and down, slip under and over each other, and all that sort of thing.

        What do you think?

        Cheers.

      • I am not a scientist but I want to be one, so maybe.

      • Actually it works for numbnuts Appell almost as well.

        He’s brought out his peer review crutch so often, OSHA has determined it is now a risk to life and limb.

      • Arch,

        One word.

        Subduction.

  3. David of course I am serious. But are you here just sniping? Peer review only has 2 reviewers. Here you have hundreds. Plus this essay cites several papers from the peer reviewed community, and thus the scientific community should be aware of these issues. However the media does not hype those papers the same way they do catastrophic climate claims. So I am just synthesizing the science and making it more accessible to the public.

    • “There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015). On the contrary, rising CO2 makes photosynthesis less costly.”

      1. Misrepresents the findings of Mackey
      2. Please remove all references to gray literature
      http://co2coalition.org/wp-content/uploads/2015/12/pH.pdf

      and that’s just 1 minute of review to flind two fatal flaws.

      Now, Jim. If you want US to do your peer review, then you better satisfy us.
      And respond how you would respond to a editor.

      So. first remove the references to the gray literature. Re write and re submit
      Next, you fundamentally mispresented Mackry. Please see pg87 and re work your entire first paragraph..

      • Steven, I took a quick poll and discovered that no one wants you to peer review and every deplorable I talked to said that, they thought all the AGW scientists should have been fired long ago because of the many correlations in personnel. The feeling is that this cause in global in scale, so it’s time to go fish on people!

        HH2016YIBOD

      • Mosher, are you still pressing the absurd view that only journal articles present science? The gray literature is where science often happens, including in blogs. You seem to have missed the Internet revolution. See for example my little essay on this from five years ago:
        https://scholarlykitchen.sspnet.org/2011/09/21/taxpayer-oa-is-already-here-in-principle-in-reports/.

      • Charles Taylor

        Mr. Mosher, the paper you reference as “gray literature” is straightforward physical chemistry (written at the freshman chemistry level). It would not be published because its basic chemistry. It’s written for people who have no training in chemistry.

      • If blog research can use grey literature, then why can’t the IPCC.

        You know sauce for the goose is sauce for the gander.

      • If blog research can use grey literature, then why can’t the IPCC.

        Sure.

        As long as it’s completely understood that IPCC “science” is no more reliable than blog “science”. EPA: take note.

      • A quick comment re gray literature. I definitely support considering gray literature and referencing it in blog posts. There are a lot of very useful analyses that are published in peer reviewed journals for a variety reasons that include:
        1) the author has no professional incentive for publishing in the peer reviewed literature
        2) the article presents updated data analysis, using established procedures (and hence not really publishable)
        3) the article is controversial, and is being squashed in the peer review process
        4) the article is a synthesis and assessment, and not really ‘new research’

        With regards to the IPCC using gray literature, this is fine, but publications from advocacy groups need extra scrutiny.

        The point is this. The scientific process should not include a filter for not considering contributions that are not peer reviewed journals. Elite science protocols should not hinder a broader discussion of scientific contributions. Unpublished articles can move the overall science process forward.

        Articles that are boring and obviously wrong don’t need to be considered (note: there are also plenty of boring and obviously wrong articles in the peer reviewed literature).

        Blog ‘science’ allows the broader scientific contributions (including gray literature) to be discussed. Some ‘elite’ scientists pay attention to blog posts; others don’t. Either way, readers are being educated, authors are getting feedback and new ideas are being generated. Sounds to me like a good thing for science.

      • bobdroege | October 14, 2016 at 2:09 pm |
        If blog research can use grey literature, then why can’t the IPCC.

        You know sauce for the goose is sauce for the gander.

        They do use grey literature. WWF (World Wrestling Federation) literature appears in their bibliographies. Grey literature is blamed for the 28 year India glacier disappearance claim.

        http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch10s10-6-2.html
        Glaciers in the Himalaya are receding faster than in any other part of the world (see Table 10.9) and, if the present rate continues, the likelihood of them disappearing by the year 2035 and perhaps sooner is very high

        http://www.thehindu.com/todays-paper/tp-national/himalayan-glaciers-will-not-disappear/article2027851.ece
        “Himalayan glaciers are not going to disappear as has been made out to be. They are quite lengthy, very big and located in very high altitude. Glaciers are also well distributed in the Himalayas,” Dr. Ajai, Group Director of Marine, Geo and Planetary Science Group at ISRO’s Space Applications Centre (SAC) Ahmedabad, told The Hindu

        If grey literature is good enough for the IPCC it should be good enough for us.

        With the packing of journal editing positions with the warming based and PAL review (per climategate files) it isn’t like peer reviewed literature is any better than grey literature anyway.

      • Either way, readers are being educated, authors are getting feedback and new ideas are being generated. Sounds to me like a good thing for science

        Hmmm. The evidence would suggest that in direct contrast to this, readers are descending further into an echo chamber of “scepticism” fuelled by the justification of reading blog published extremely poor work with painfully obvious flaws.

        Peer review is evidently not perfect, but it is *much* better than echo chamber review.

      • Matthew Marler

        Steven Mosher: http://co2coalition.org/wp-content/uploads/2015/12/pH.pdf

        Thank you for the link to that paper. Did you have a point in citing it?

      • verytallguy:

        Yes – RealClimate is terrible.

        But what about the other blogs?

        Just kidding – I am sure you are not referring to all blogs.

      • Matthew

        I think mosh’s point in linking to the study was to confirm that, accordng to the summary, man has very little effect on oceanic ph and presumably, by inference, that we are having little impact on coral colonies

        Tonyb

      • Peer review is no guarantee of truth or honesty. As the editor of the Lancet recently admitted, up to half of the published peer reviewed medical literature may be false.

        The point is argue the evidence not the arguer.

      • I don’t know what Mosher’s position on the CO2Coalition paper is but I think this is bunk

        “This is hardly surprising, given the relative insensitivity
        of ocean pH to large changes in CO2 concentrations that we have discussed above, and
        given the fact that the pH changes that do occur are small compared to the natural
        variations of ocean pH in space and time.”

        and Steele does indeed misrepresent the findings of Mackey

        That study shows that coccolithophores show reduced calcification and increased levels of aberrant or degraded coccoliths with increased CO2 among other affects.

      • bobdroege you appear to have a very selective awareness. YOu try to snipe misrepresented Mackey’s study, but let me quote, “Coccolithophores appear to rely primarily on aqueous CO2 for photosynthesis, while preferring to access HCO3– for calcification (Buitenhuis et al., 1999; Bach et al., 2013). Consequently, rising CO2 tends to promote photosynthesis over calcification and reduce the ratio
        of inorganic to organic carbon in these organisms

      • Steven Mosher: Next, you fundamentally mispresented Mackry. Please see pg87 and re work your entire first paragraph..

        P87 displays, and discusses, much variability. What exactly did he write that “fundamentally” misrepresented Mackey? Their overall conclusion is that CO2 benefits are small and variable, with some as yet unexplored “maybes”.

      • It’s important to realize that coccolithophores tend to precipitate CaCO3 as shed coccoliths as variable behavior. This means that a bloom can draw down CaCO3, lowering the pH and raising the level of undissociated carbonic acid (H2CO3) until it reaches some equilibrium with its own behavioral standards.

        Not only that, but given the normally slow kinetics of conversion between CO2 and H2CO3, this process can be mostly restricted to some internal environment where levels of carbonic anhydrase (CA) are high.

        Any extra H2CO3 not converted to CO2 and used for photosynthesis by coccoliths can be (more slowly) converted to CO2 in the wider environment (primarily by free-floating CA’s, AFAIK), thus raising the level of dissolved CO2. Which, in turn, can equilibrate with atmospheric CO2, effectively contributing to increasing the global pCO2.

      • Steven I hope you know I am one who takes you seriously.

        But at times you are a real dick.

      • Bob D,

        They do.

        And they also are referred to as the gold standard.

      • Anyone besides me interested in seeing vtg’s “evidence”?

        On second thought, seeing a brown substance under his finger nails might impact my appetite.

      • Steele asked for a peer Review

        I criticized the IPCC for using Gray literature and NOT A SINGLE ONE OF YOU thought I was wrong to criticize them.

        Comes now Steele

        Goose gander.

        Deal with it.

        he wants my review.. he BUTCHERED MACKEY and seriously misrepresented him to the point of MISCONDUCT and he uses gray literature. If he has a proper cite for the same facts as the gray literature he should use it.

        Look. You publish something and ask for review and then you want to WHINE about the review

        grow up. and fix the problems. you asked me to play ref.. well I just did.

        Steele 15 yard penalty and loss of down.

      • I’m not going to pay $36 for a paper in Nature Climate Science when I’ve already learned a lot of what they publish isn’t worth reading. A subscription to Scientific American is as far as I go, given Nature’s very clear political bias.

      • Moshers engages in unsupported character assassination that is nothing more than slander, saying “he [I] BUTCHERED MACKEY and seriously misrepresented him to the point of MISCONDUCT”

        I cited Mackey twice. First , “There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015)” Instead of sniping and distorting, please list the examples where lower pH inhibited photosynthess.

        Second “Globally different photosynthesizing organisms have demonstrated a variety of responses to rising CO2 but altogether there appears to be few negative effects on photosynthesis due to elevated CO2 and depending on the species small to large benefits (Mackey 2015). “ The content of theat paper fully support my statements.

        Again below is a list of Mackey quotes that support my statements. Mosher and Willard have been asked to present evidence by Mackey that lower pH inhibits photosynthesis. They dont. Instead they take the low road of more dishonest personal attacks. Mosher gets disqualified for flagrant fouls.

        _ Photosynthesis in Prochlorococcus was unresponsive to pCO2

        _Elevated CO2 caused higher phycobilin and chlorophyll-a content in Synechococcus, leading to a higher
        light harvesting efficiency (α) and a lower light saturation constant (Ek). High CO2 alone did not increase maximal photosynthetic rates in this strain; however, when high CO2 was combined with a warmer temperature (4°C above the control), maximal photosynthetic rates increased twofold relative to elevated temperature alone.

        _At least one genus of picoeukaryotes (Ostreococcus) appears to be strongly enhanced by elevated CO2, with growth rates almost doubling at 1,000 ppm (Schaum et al., 2013).

        _(Regards diazotrophic/ nitrogen fixing plankton) To date, almost all studies suggest that N2 fixation will increase in response to enhanced CO2

        _T. pseudonana [a diatom] showed an increased maximum photosynthetic rate (Pmax) and an increased PE curve halfsaturation constant (Ek) under high CO2, suggesting that more light was required to saturate photosynthesis (Sobrino et al., 2008). Growth rate also increased by 20% under high CO2 in this experiment

        _Under enhanced CO2, Phaeodactylum [diatom} shows increased photosynthetic electron transport rates, but no change or very modest increases in growth
        or C fixation

        _A mesocosm experiment conducted in Bergen, Norway, reported that net community carbon consumption and net photosynthesis increased under increased CO2 for a mixed community of diatoms and coccolithophores (Riebesell et al., 2004). In a later mesocosm study with a different initial community composition, diatoms were outcompeted at high CO2 while picoplankton were strongly stimulated (Riebesell et al., 2013). A third mesocosm experiment with two different diatom species (Skeletonema costatum and Nitzschia spp.) under nutrient replete conditions showed that only S. costatum increased growth rate under enhanced CO2 (Kim et al., 2006). Therefore, the effect of enhanced CO2 on natural diatom populations depends on the species of diatoms, as well as on the overall composition of the phytoplankton community.

        _Coccolithophores appear to rely primarily on aqueous CO2 for photosynthesis, while preferring to access HCO3 – for calcification (Buitenhuis et al., 1999; Bach et al., 2013). Consequently, rising CO2 tends to promote photosynthesis over calcification and reduce the ratio of inorganic to organic carbon in these organisms

        _found that photosynthesis and growth in most species were not C saturated under present-day CO2 concentrations. Because C3 photosynthesis is more sensitive to the direct effects of CO2 concentration, future increases in CO2 will most likely increase photosynthetic rates and growth in marine macrophytes,

      • Steven Mosher: he BUTCHERED MACKEY and seriously misrepresented him to the point of MISCONDUCT and he uses

        Dr Mackey is named “Katherine”, so change the relevant pronoun.

        You do not cite even one mistake in Jim Steele’s use of the paper by Mackey et al. Jim Steele did not in fact “BUTCHER” it or misrepresent it. It’s hard to keep track of ALL your mistakes.

    • Jim Steele,

      Keep it up. Nothing wrong with thinking about Nature. It used to be called Natural philosophy, I believe. Amazing that the GHE mob have no problem with Arrhenius pondering about the relationship between CO2 and glaciation. Maybe not quite so enthusiastic about his support of eugenics?

      It looks as though David Appell claims at least some journalistic expertise. From his resume –

      “Graduate Program in Creative Writing (15 hours completed), Arizona State University.”

      Mosher the scientist. Appell the journalist and critic. Oh, and three years as a teaching assistant.

      Delusional psychosis? Legend in his own lunchbox? The world wonders!

      Cheers.

      • While reading this tour de force post, I was wondering how someone without the requisite academic credentials would respond. We found out on cue. And as usual it was not impressive.

    • “But are you here just sniping?”

      Is there ever a time when appell ISN’T here just sniping? ☺

  4. Wow, that’s a blockbuster hit of fresh Gaia Theory.

    Ferdinand & Bart must be double-checking the references.

    This post, to the degree that it is solid, obviously puts teeth on Bart’s “dynamic feedback CO2” model.

    C’mon Bart when are we going to see a full-blown post from you? It’s all there in pieces.

    By the way, slightly related, there’s a bunch of mp3 files at the Royal Society for recent conf on Ocean Ventilation and Deoxygenation – https://royalsociety.org/science-events-and-lectures/2016/09/ocean-ventilation/

  5. PS – including a talk by Andrew Watson, one of Lovelock’s disciples, that highlights the regularity of Oceanic Anoxic Events.

  6. Pingback: How Gaia And Coral Reefs Regulate Ocean pH | The Global Warming Policy Forum (GWPF)

  7. Jim

    I found this relatively basic guide to ph levels to be useful and learn that natural ph of seawater ranges from 7.5 to 8.5

    http://www.fondriest.com/environmental-measurements/parameters/water-quality/ph/#p9

    Also that it can be affected by man made (acidic rain and mining) and natural causes.

    I live adjacent to the Torbay geopark in southwest England. It consists of limestone cliffs and red devonian sandstones. It also has extensive coral, although I understand that cold water coral operates completely differently to those in tropical waters .

    I understand co2 is relatively well mixed in the atmosphere around the world but does the same apply to oceanic (and closed water) ph levels? Are there large patches within the ocean that are acidic and large patches that are alkaline with quite different ph levels or do they mix well in order to produce the ‘average’ ph given above?

    Leading on from that, are coral reefs in Australia affected by strictly localised factors or are they subject to world wide influences?

    If I could measure the ph levels adjacent to the limestone and the sandstone cliffs around here would it be close to the ph levels in (say) the Great barrier reef?

    Just trying to get back to basics before I read Jims piece in more detail

    tonyb

    • I found this relatively basic guide to ph levels to be useful and learn that natural ph of seawater ranges from 7.5 to 8.5

      https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3242773/

      The range is a little wider than that.

      • PA

        From my link

        ‘Seawater has a pH around 8.2, though this can range between 7.5 to 8.5 depending on its local salinity. pH levels will increase with salinity until the water reaches calcium carbonate (CaCO3) saturation ¹⁶. The oceans generally have a higher alkalinity due to carbonate content and thus have a greater ability to buffer free hydrogen ions ‘

        tonyb

      • The measured PH at 15 locations had a high of a little over 8.4 and a minimum of a little less than 6.7.

        This is only measurement at 15 locations and isn’t a worst case min/max or worst case mean range.

        Your statement is probably accurate for the mean (the mean at 15 locations was 7.6 to 8.2). But when the ocean is nice (not mean) the range is wider.

  8. The main effect of atmospheric CO2 increase on land and marine ecosystems is to increase ecosystem productivity. This is not only obvious but supported by observations. Together with the increase in temperatures it means more energy flowing through the ecosystem.

    If we would stop wasting our resources in a futile attempt at stopping climate change and dedicate them to restore the natural wold, climate change would help us in that task.

    • In my opinion conservation groups are failing us. Now is the time to act at conservation, not climate change. However the money is at climate change.

  9. > There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015). On the contrary, rising CO2 makes photosynthesis less costly.

    Here’s Mackey’s abstract:

    All phytoplankton and higher plants perform photosynthesis, where carbon dioxide is incorporated into biomass during cell growth. Ocean acidification (OA) has the potential to affect photosynthetic kinetics due to increasing seawater pCO2 levels and lower pH. The effects of increased CO2 are difficult to predict because some species utilize carbon concentrating mechanisms that buffer their sensitivity to ambient CO2 levels and require variable energy investments. Here, we discuss the current state of knowledge about the effects of increased CO2 on photosynthesis across marine photosynthetic taxa from cyanobacteria and single-celled eukaryotes to marine macrophytes. The analysis shows that photosynthetic responses to OA are relatively small for most investigated species and highly variable throughout taxa. This could suggest that the photosynthetic benefits of high CO2 are minor relative to the cell’s overall energy and material balances, or that the benefit to photosynthesis is counteracted by other negative effects, such as possible respiratory costs from low pH. We conclude with recommendations for future research directions, such as probing how other physiological processes respond to OA, the effects of multiple stressors, and the potential evolutionary outcomes of longterm growth under ocean acidification.

    http://tos.org/oceanography/assets/docs/28-2_mackey.pdf

    • Willard, Read the whole paper. See the list of I quoted from Mackey. Also note that Mackey mentioned that some of the experiments showing little increased photosynthesis from higher note this may be due the efficiency of carbom concentrating mechanisms.

      • > Read the whole paper.

        No quotes contradict the abstract’s claim that photosynthetic responses to OA are relatively small for most investigated species, Jim. Your “CO2 makes photosynthesis less costly” fails to be materially supported by the paper. More importantly, you omit other energy costs.

        Paying lip service is not enough: you need to think like a system theorist, Jim.

      • Chris Schoneveld

        Willard, during the Cretaceous coral growth was more abundant than today due to high CO2 levels and high temperatures with a pH of ~7.5, suggesting that the level of alkalinity is not a dominant factor.

      • Chris, here’s what Mackey & al write in the the relevant paragraph from their conclusion:

        MOVING FORWARD IN PHOTOSYNTHESIS–OA RESEARCH

        Photosynthetic responses to enhanced CO2 under OA are remarkably diverse, and variability exists both between and within taxonomic groups (Figure  2). As the substrate for photosynthesis, elevated CO2 would be expected to increase photosynthetic rates either directly by relieving carbon limitation or indirectly by lowering the energy required to concentrate CO2 against a smaller concentration gradient. Nevertheless, despite the growing body of literature on the topic, clear trends in the photosynthetic responses of phytoplankton to elevated CO2 have not emerged, and the positive effects, if any, are small (Figure  2). Additionally, many studies finding “no effect” of OA are likely not published, resulting in a bias in the literature. That no significant difference is apparent even in light of this bias suggests the net effects of OA on photosynthesis are minor for a large proportion of phytoplankton species. The small effect could indicate that the benefits afforded by high CO2 are small relative to the cell’s overall energy and material balances. Alternatively, the small effect of OA could indicate that its expected benefit to photosynthesis is counteracted by other negative effects, such as possible respiratory costs from low pH. Moving forward in OA research, experiments should encompass a broader suite of measurements to probe how different physiological processes in addition to photosynthesis respond to OA.

        Have you looked at figure 2?

        When you’ll acknowledge that Mackey & al doesn’t support Jim’s position, I’ll see what I can do about your bait and switch. The scale switch, which echoes the usual “geological perspective,” deserves due diligence.

      • Chris Schoneveld

        Willard, the problem is that Willard talks about coral reefs whereas the Mackey study focuses on phytoplankton.

      • Chris Schoneveld

        correction: the problem is that Jim talks about coral reefs

      • Willard, You are cherry picking one sentence in the abstract that takes the whole paper out of contrext where they are speculating on why some species do not show a greater increase in photosynthesis. Again if you read the whole paper Mackey reports several species do benefit greatly while others not so much. I provided a list of those statements at the very beginning of the comments. Mackey does not argue CO2 has been detrimental to photosynthesis. Mackey does say allude to reasons why some species do not show a measured increase in photosynthesis, such as when CO2 rises, because Carbon Concentrating mechanisms create a high rate of photosynthesis, under higher CO2 they down regulate that mechanism so photosynthetic rates remain unchanged.

        Again Willard provide a list where Mackey says rising CO2 has been detrimental to photosynthesis.

        And explain why coral acidify their internal vesicles to pH4. Otherwise you are just sniping.

      • http://science.sciencemag.org/content/early/2015/11/24/science.aaa8026

        A compilation of 41 independent laboratory studies supports our hypothesis. Our study shows a long-term basin-scale increase in coccolithophores and suggests that increasing CO2 and temperature have accelerated the growth of a phytoplankton group that is important for carbon cycling.

        Coccolithophores (a phytoplankton) have shown a 7x to 10x increase in calcification per Coccolithophore.

        Further this study has been quoted at ClimateEtc numerous times.

        Proof the plankton are increasing would seem to refute claims that they won’t.

        I noticed Willard highlighted all of a statement except “This could suggest that” so the statement might not suggest that also. All of the sections he quoted were riddled with weasel words.

      • > the problem is that Jim talks about coral reefs

        Problems with that squirrel, ChrisS, are:

        – there are many problems;

        – Jim cites Mackey 2015;

        – Mackey 2015 does not support Jim’s claim that rising CO2 makes photosynthesis less costly;

        – photosynthesis is more expensive than calcification.

        Better luck next time.

        ***

        > You are cherry picking one sentence […]

        This is false, Jim.

        First, I quoted the whole abstract in Mackey 2015. Then I quoted the whole paragraph relevant to your claim from the conclusion.

        We can look at figure 2 if you please:

        Tell me with a straight face that this paper supports your claim.

        But speaking of cherrypicking, you forgot to tell Denizens that not all calcifying organinisms up-regulate pH.

      • Willard totally fabricates what I wrote and reveals his scientific misunderstanding.

        Willard dishonestly writes Jim says, “– photosynthesis is more expensive than calcification.”

        Never said that. What I quoted from peer reviewed science is that calcification only requires 1% of the energy produced by photosynthesis.

        Both processes require energy, however photosynthesis ultimately stores energy while calcification expends energy!

      • > Never said that.

        Neither did I say Jim did, and I was referring to ChrisS’ squirrel.

        From an energetic viewpoint, photosynthesis is the name of the game.

      • Nice Willard. Took me all of 15 seconds to find that Steele had BUTCHERED Mackey

        What a joke.

      • Yes it took Mosher 15 seconds to go delusional!

      • Jim

        It is simple.

        I read your reference to Mackey
        YOU asked US to REVIEW

        I checked Mackey

        YOU FUNDAMENTALLY MISREPRESENTED HIS PAPER.

        you attributed claims to him that he does not make.
        your work stands on your false claims, and so FALLS on those
        material misrepresentations.

        you asked for a review.. you got it.

        Reject, misrepresents the work it cites

      • Mosher,

        I await your apology!

        You continue to lie that I attributed claims to Mackey’s paper she did not make, yet you have NEVER ever articulated what those claims were and how they were conttradicted. You need to support your ad hom deceptions with scientific evidence. Otherwise shut up and take your lies with you.

        Here my 2 claims regards the Mackey paper:

        1. “There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015).”

        2. “Globally different photosynthesizing organisms have demonstrated a variety of responses to rising CO2 but altogether there appears to be few negative effects on photosynthesis due to elevated CO2 and depending on the species small to large benefits (Mackey 2015).”

        Anyone who reads the full text of the paper will see what a dishonest sniper Steve Mosher (as well as Willard) is!!!

      • Jim, I suggest you acquaint yourself with Saul Alinsky’s “Rules for Radicals” before you continue to attempt to debate with such clearly dishonest propagandising individuals as M osher and W illard, as you will never get them to admit they are wrong, they will spend dozens of posts asserting that ‘Balck is White’ so as to tie you in knots and distract you from more important topics.

        Actually, it is in reality an admission that they are actually afraid of you and your erudition.

        https://en.wikipedia.org/wiki/Rules_for_Radicals

        They are clearly intimately acquainted with them, and if you are not at least familiar, they will invariably have you at a disadvantage.

        Another important reference in this vein is Memory Vault’s treatise on the “Post Modern Mamba” which I believe i have previously drawn to your attention.

        If not (and for anyone who is unacquainted with it), here’s the link again.

        https://libertygibbert.com/2010/08/09/dobson-dykes-and-diverse-disputes/

        The other term for the technique favoured by the above is known as the “Clown Dance”, incidentally.

      • catweazle666, Thank you for your support. I do not really expect an apology from Mosher or Willard. That would only come from honest men who are sincerely in search of the truth and meaningful scientific debate. None the less they should apologize for their despicable lies. I can only hope people read the Mackey paper and see for themselves how disgustingly Mosher and Willard have distorted the truth, obfuscated meaningful science, and denigrate my efforts.

        You did introduce me to the Post Modern Mamba and rightfully applied it to Brandon Gates. It was no surprise he tried to add support to Willard and Mosher’s deception.

    • Willard you are wrong and deliberately trying to obscure the Mackey paper and the mechanisms discussed in this paper.

      I cited Mackey twice. First , “There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015)” Instead of sniping and distorting, please list the examples where lower pH inhibited photosynthess.

      Second “Globally different photosynthesizing organisms have demonstrated a variety of responses to rising CO2 but altogether there appears to be few negative effects on photosynthesis due to elevated CO2 and depending on the species small to large benefits (Mackey 2015). “ The content of theat paper fully support my statements. I have asked you list any detrimental effects in the Mackey paper and you have avoided that. And as I listed above Mackey reported several groups of organisms that have benefitted greatly as well as those that showed no impact of higher CO2.

      Willard, you totally misunderstand the sentence you cherry pick and take the whole paper out of context. The first part of the abstract sentence you are obsessed with states, “The analysis shows that photosynthetic responses to OA are relatively small for most investigated species and highly variable throughout taxa. This could suggest that the photosynthetic benefits of high CO2 are minor relative to the cell’s overall energy and material balances,” …

      Notice Mackey is acknowledging “the photosynthetic benefits of high CO2”. He goes on to say the benefits may be relatively minor relative to the overall energy budget, but nonetheless it is beneficial again confirming what I wrote.

      Mackey continued, “or that the benefit to photosynthesis is counteracted by other negative effects, such as possible respiratory costs from low pH.” This statement is totally speculative and not discussed in the review. Hence it should never have been in abstract unless there was some sort of gatekeeper pressure. That whole sentence taken together reveals Mackey was expecting greater benefits from higher CO2, and he is not sure why they are no more noticeable. None the less as listed at the beginning of the comments section, Mackey reports several organisms with enhanced photosynthesis. If you read the whole paper Mackey never argues CO2 has been detrimental to photosynthesis.

      Instead Mackey’s review should have emphasized the issue he reviewed such as difficulty in measuring the benefits. The difficulty in assessing the benefits are due to many possible effects. Mackey does allude to some species that do not show a measured increase in photosynthesis when CO2 rises, because Carbon Concentrating Mechanisms create a high rate of photosynthesis under low CO2 by concentrating bicarbonate ions. Then under higher CO2 they down regulate that mechanism so photosynthetic rates remain unchanged. However that down regulation would save energy, and unless those studies were using an energtetoc metric they would not beware of the energetic advantages.

      Although Mackey cites several examples of the benefits, Willard and Mosher try to suggest one speculative sentence they misunderstand, negates the ample evidence in the bulk Mackey’s review. And my arguments do not hinge on the Mackey review paper alone as much as the snipers try to misdirect. I specifically noted coral acidify their internal vesicles to pH4 to improve photosynthetic rates. That process in itself illustrates why lower pH and more CO2 benefits photosynthesis. All photosynthesizing organisms require CO2 as a substrate for RUBISCO in order to synthesize carbohydrates.

      • > I cited Mackey twice. First , “There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015)”

        You forget the sentence that follows in your “essay,” Jim:

        On the contrary, rising CO2 makes photosynthesis less costly.

        This paper does not support that statement.

        Everything I cited in that paper shows this.

        That’s a checkmate.

      • Willard: “That’s a checkmate.”

        That’s a remarkable talent you’ve got there, Willard.

        There can be very few who are capable of checkmating themselves.

        You ought to post a description of how you manage it some time.

        Or better still, why you bother, when all you do is make a fool of yourself.

      • Willard says checkmate.

        ROTFLMAO

        Willard you have a very selective way of reading and isolating snippets of information to dishonestly support your sniping. My sentence that followed was an introduction to the analyses that followed. Anyone who comprehends bioenergetics would see that immediately.

        Mackey’s review was cited because it showed photosynthesis was NOT inhibited by rising CO2, and offered ample examples of rising CO2 promoting photosynthesis. You try to dishonestly wordsmith those facts into some sort of contradiction with my claims. You have been repeatedly asked to list where Mackey states photosynthesis was inhibited but you engage in distortions. My citation of Mackey simply provided research that shows rising CO2 does not inhibit photosynthesis.

        My following paragraphs discuss why lower pH lowers the energetic costs of pumping bicarbonate ions and benefit photosynthesis. Perhaps Willard fails to understand the energy required to pump ions against a concentration graident. Or perhaps Willard ignores the science because it exposes is lack of scientific understanding.

        All Willard has done is deflect the consequences of well established carbonate chemistry. Does Willard fail to understand the benefits of lower pH and its effect on gradients and energy required for pumping? Does he fail to comprehend the benefits that drove why coral evolved mechanisms that reduce internal pH to pH 4?

      • > Mackey’s review was cited because it showed photosynthesis was NOT inhibited by rising CO2, and offered ample examples of rising CO2 promoting photosynthesis.

        Yet the authors of Mackey 2015:

        – stated in their abstract that the photosynthetic benefits of high CO2 are minor relative to the cell’s overall energy and material balances, or that the benefit to photosynthesis is counteracted by other negative effects, such as possible respiratory costs from low pH;

        – declared in their conclusion that clear trends in the photosynthetic responses of phytoplankton to elevated CO2 have not emerged, and the positive effects, if any, are small;

        – showed a figure where the effects of elevated CO2 on phytoplanktons were variable between and within taxonomic groups, but in all cases the effect is small.

        Even notwithstanding the publication bias, the authors conclude that “either the benefits afforded by high CO2 are small relative to the cell’s overall energy and material balances” or that “the small effect of OA could indicate that its expected benefit to photosynthesis is counteracted by other negative effects.”

        So right after citing Mackey 2015, Jim goes on to claim a thesis (“on the contrary, rising CO2 makes photosynthesis less costly.) whose relevance is undermined by Mackey 2015.

        You just can’t make this up.

      • “You just can’t make this up.”

        But you do, Willard.

        All the time!

      • ROTFLMAO

        Willard continues to avoid providing any evidence from Mackey or any other papers showing rising CO2 inhibits photosynthesis or any evidence that contradicts the argument that rising CO2 benefits photosynthesis. The best Willard can do is repeat ad nauseum that Mackey believes the benefits of rising CO2 are minor. Nonetheless minor benefits are still a good thing.

        This essay must hit close to the truth. Other wise why would Willard incessantly try to promote FUD, and ignore the fact that rising CO2 has NOT had a negative impact on photosynthesis.

      • > Willard continues to avoid providing any evidence from Mackey or any other papers showing rising CO2 inhibits photosynthesis or any evidence that contradicts the argument that rising CO2 benefits photosynthesis.

        The reason being that there’s no need to do so.

        It suffices to recall that Mackey 2015, Jim’s own citation, concludes that “the photosynthetic benefits of high CO2 are minor” or that “clear trends in the photosynthetic responses of phytoplankton to elevated CO2 have not emerged, and the positive effects, if any, are small“.

        How these variable, minor, and small effects are supposed to support Jim’s rediscovery of Gaia is left as an exercise to Denizens.

        Go team!

      • Willard and Mosher drop cogent critiques, Steele drops insults. Shocking.

      • Based on past experience, I knew it would not be longer before Brandon Gates would try to perpetuate the dishonest sniping as he does now.

        I can only assume Gates is clueless about what constitutes a “cogent critique”. But perhaps I am biased by his past. So instead of more sniping perhaps Gates can repeat what he thinks was their “cogent critiques”

    • May I point out many of you are arguing based on a single paper?

      Unless Mackey is the single greatest scientist of all time, it starts to sound childish when you all argue over what his paper means.

      • > Unless Mackey is the single greatest scientist of all time, it starts to sound childish when you all argue over what his paper means.

        Even if Mackey were, it may still sound childish, TimG.

        Mackey’s conclusions undermine Jim’s – he claims more CO2 benefits photosynthesis while Mackey found that the positive effect of high CO2 on photosynthesis were negligible.

        If you prefer, take a look at this other paper:

        Ocean acidification (OA) is the reduction in seawater pH due to the absorption of human-released CO2 by the world’s oceans. The average surface oceanic pH is predicted to decline by 0.4 units by 2100. However, kelp metabolically modifies seawater pH via photosynthesis and respiration in some temperate coastal systems, resulting in daily pH fluctuations of up to ±0.45 units. It is unknown how these fluctuations in pH influence the growth and physiology of the kelp, or how this might change with OA. In laboratory experiments that mimicked the most extreme pH fluctuations measured within beds of the canopy-forming kelp Ecklonia radiata in Tasmania, the growth and photosynthetic rates of juvenile E. radiata were greater under fluctuating pH (8.4 in the day, 7.8 at night) than in static pH treatments (8.4, 8.1, 7.8). However, pH fluctuations had no effect on growth rates and a negative effect on photosynthesis when the mean pH of each treatment was reduced by 0.3 units. Currently, pH fluctuations have a positive effect on E. radiata but this effect could be reversed in the future under OA, which is likely to impact the future ecological dynamics and productivity of habitats dominated by E. radiata.

        https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4882519/

        Gaia frowns upon claims of linear relationships.

      • Willard,

        Based just on what I have read here, my overall take on Dr Mackey’s paper is that it has advanced our understanding by a small increment, and leaves us still in the dark on what really happens with changes in pH. I don’t see where Dr Steele’s conclusions are completely contrary to Dr Mackey ‘s research. Has he expanded on them beyond what her paper would support? Perhaps. (Don’t have time to digest both papers. I still have to work for a living. In fact by this time tomorrow I’ll likely be out in the field, supporting restoration work. And if this storm is as strong as they are predicting, I could be out for the next 2 weeks or longer.)

        Assuming he has, why don’t you and Steven say that, instead of your over the top condemnation?

      • I don’t think “Mackey & al doesn’t support Jim’s position” is over-the-top, TimG, so please don’t coatrack me with Moshpit.

        Had Jim clarified that his own claim goes further than Mackey, and did so without paying lip service to Gaia, he’d have taken the criticism like a boss.

        I mean, come on – Jim can’t even accept that he should have cited Maier-Reimer 1996, because that’s where what has been estimated has been estimated.

        Mackey’s a she, BTW.

        PS: If you don’t have access to an RSS reader, I doubt you could have read the whole exchange.

      • Willard your attacks have dishonest and misleading and thus as criticized “over the top” which is being kind.

        You still have failed to present any evidence showing that i misrepresented Mackey’s paper. And as said before, the very fact that CO2 benefits photosynthesis in only a minor way is exactly what the negative feedbacks and homeostasis of gaia theory predicts. Mackey discusses when CO2 is limited organisms up-regulate their carbon concentrating mechansims, When CO2 is more plentiful the down regulate and save energy, which is exactly the kind of feedbacks I discussed and why studies find little change in photosynthesis even when CO2 is increased to 1000 and 5000 ppm.

        Then you dishonestly fabricate “Jim can’t even accept that he should have cited Maier-Reimer 1996, because that’s where what has been estimated has been estimated.” I understand the point but did not respond for 2 reasons.

        First it was just another irrelevant snipe that you obsessed with in order to redirect the discussion. It changed nothing. Even if my citation could have been more precise, it was not misleading or dishonest. But that minor glitch has been the extent of your “cogent scientific critique” ROTFLMAO

        Second it does nothing to change the point of the argument. The point I made was “without the biological pump, pre-industrial atmospheric CO2 would have out gassed and raised atmospheric CO2 to 500 ppm, instead of the observed 280 ppm.” That assertion remains unchallenged and illustrates how important the biosphere is to ocean pH and atmospheric CO2. That I cited an author who stated the same thing and then cited the original paper is immaterial to the discussion but only a point you use to obfuscate.

  10. > It has been estimated that without the biological pump, pre-industrial atmospheric CO2 would have out gassed and raised atmospheric CO2 to 500 ppm, instead of the observed 280 ppm.

    The proper citation under “estimated” should be Maier-Reimer 1996:

    http://link.springer.com/article/10.1007/s003820050138

    There is also an omission of the physical pump.

    ***

    Here’s a link to Maier-Reimer 1996 even GregG will be able to find:

    http://www.uta.edu/faculty/awinguth/Publications/publications/1996/Maier-Reimer-ClimDyn-1996.pdf

    Here’s the abstract:

    We discuss the potential variations of the biological pump that can be expected from a change in the oceanic circulation in the ongoing global warming. The biogeochemical model is based on the assumption of a perfect stoichiometric composition (Redfield ratios) of organic material. Upwelling nutrients are transformed into organic particles that sink to the deep ocean according to observed profiles. The physical circulation model is driven by the warming pattern as derived from scenario computations of a fully coupled ocean-atmosphere model. The amplitude of the warming is determined from the varying concentration of atmospheric CO2. The model predicts a pronounced weakening of the thermohaline overturning. This is connected with a reduction of the transient uptake capacity of the ocean. It yields also a more effective removal of organic material from the surface which partly compensates the physical effects of solubility. Both effects are rather marginal for the evolution of atmospheric pCO2. Running climate models and carbon cycle models separately seems to be justified.

    The last sentence seems to reinforce the so-called “non-Gaia assumption,” whatever that means.

    • Damn Willard. You are one of the most dishonest people I have come across.

      I wrote, “It has been estimated that without the biological pump, pre-industrial atmospheric CO2 would have out gassed and raised atmospheric CO2 to 500 ppm, instead of the observed 280 ppm.”

      I linked to a paper that wrote For example, without the biological pump, the pre-anthropogenic atmospheric CO2 concentration would have been >500 ppm (parts per million by volume) rather than 280 ppm v (Maier-Reimer et al., 1996).

      Everything I wrote was factual, but again the internet sniper Willard tries to distort published evidence.

  11. The biological control of pH isn’t only around coral reefs. It is predominant in estuaries. That was the root error in the PMEL oyster acidification nonsense described in guest post here Shell Games a couple of years ago.
    Very detailed and informative reference post, Dr. Steele. Thanks.

    • The biological control of pH isn’t only around coral reefs. It is predominant in estuaries.

      Also coccolithophore blooms.

  12. “Billions of us will die” and only the “few breeding pairs of people that survive will be in the Arctic”.

    Overall, sounds pretty much like the plot line of Noah, the remake… only with Al Gore as a modern-day Methuselah in the Left’s tale about Westerners — mostly free market Americans — being judged by their Judeo-Christian God for developing spreading the evil of mechanized transport.

    • “breeding pairs”
      Very soon breeding pairs will not be required for reproduction
      This is the most significant change in the operating system that Gaia has ever hatched.
      Pales in comparison to our puny little release of ‘sequestered’ carbon.

  13. This post prompted some googling which resulted in this interesting longer term perspective of both global warming but also life giving CO2:

    How has the total biomass of the earth changed over time?

    Evolution of the cumulative biosphere pools for procaryotes (red), eucaryotes (green), and complex multicellular life (brown). The black curve shows the evolution of atmospheric partial pressure of oxygen.

    As global temperatures kept dropping the biomass kept increasing. At around 0.54 Gyr ago complex life forms showed a rapid explosion. After that there has been a continuous decrease due to decreasing phanerozoic surface temperatures being below optimum for prokaryotes and eukaryotes. The decrease at .35 Gyr is related to the rise of Vascular plants. Presently the surface temperature of about 15C is near optimum for complex life forms. Into the future, the life spans of complex multicellular life and of eucaryotes end at about 0.8 Gyr and 1.3 Gyr from present, respectively. In both cases the extinction is caused by reaching the upper limit of the temperature tolerance window ( 30◦C for multicellular and 45◦C for eucaryotes). The ultimate life span of the biosphere, i.e. the extinction of procaryotes, ends at about 1.6 Gyr. In this case the extinction is not caused by the temperature leaving the tolerance window but by a too low atmospheric CO2 content for photosynthesis.

  14. > In addition on a per molecule basis, the cost of calcification requires less than 1% of the energy produced by photosynthesis (McCulloch 2012).

    Here’s the abstract of McCulloch 2012:

    Rapidly rising levels of atmospheric CO2 are not only causing ocean warming, but also lowering seawater pH hence the carbonate saturation state of the oceans, on which many marine organisms depend to calcify their skeletons. Using boron isotope systematics, we show how scleractinian corals up-regulate pH at their site of calcification such that internal changes are approximately one-half of those in ambient seawater. This species-dependent pH-buffering capacity enables aragonitic corals to raise the saturation state of their calcifying medium, thereby increasing calcification rates at little additional energy cost. Using a model of pH regulation combined with abiotic calcification, we show that the enhanced kinetics of calcification owing to higher temperatures has the potential to counter the effects of ocean acidification. Up-regulation of pH, however, is not ubiquitous among calcifying organisms; those lacking this ability are likely to undergo severe declines in calcification as CO2 levels increase. The capacity to up-regulate pH is thus central to the resilience of calcifiers to ocean acidification, although the fate of zooxanthellate corals ultimately depends on the ability of both the photosymbionts and coral host to adapt to rapidly increasing ocean temperatures.

    • What should we do now, Willard?

    • Again Willard you try to misdirect. Again I doubt you read or understandd the whole paper. The abstract you quote does not negate a thing I said. In addition on a per molecule basis, the cost of calcification requires less than 1% of the energy produced by photosynthesis (McCulloch 2012).

      With the caveat the coral may be subjected to temperature opitmum, McCulloch also wrote, “we also model the future response of coral reefs
      to both global warming with mean tropical sea surface temperatures
      (SSTs) of 2 C higher (see Methods) and a future scenari0 with pCO2 increasing from present-day levels to 1,000 microatm by the year 2100 (IPCC A1FI). For this scenario, our IpHRAC model predicts either unchanged or only minimal effects on calcification rates.

      MCCullocjh continued, “From a strictly chemical and kinetic perspective, our IpHRAC model therefore indicates that ocean acidification combined with
      rising ocean temperatures should have only minimal effects on
      coral calcification, a direct outcome of their ability to up-regulate
      pH at the site of calcification.

      McCulloch also added the caveat that organisms that can not up regulate may be vulnerable and cites a paper on foraminfiera by Moy but that paer has been challenged. Perhaps Willard you can cite the studies that show the species that can not up regulate.

      McCulloch also adds the caveat that the ability to photosynthesize and calcify be affected by bleaching. But as I have detailed elsewhere, the ability of coral to shift and shuffle their symbionts has made the very resilient.

      http://landscapesandcycles.net/coral-bleaching-debate.html

      • > The abstract you quote does not negate a thing I said.

        It actually mentions some things Jim failed to disclose, i.e. that

        Up-regulation of pH, however, is not ubiquitous among calcifying organisms

        Those lacking this ability are likely to undergo severe declines in calcification as CO2 levels increase.

        The fate of zooxanthellate corals ultimately depends on the ability of both the photosymbionts and coral host to adapt to rapidly increasing ocean temperatures.

        But yet again, Jim prefers to argue the arguer instead of the evidence.

      • Willard engages in the typical internet sniping tactic of suggesting I did not report everything in the science literature. In other words I did not write an enycylopedia on the subject, I only wrote an essay. Yet my claim stands. Lower pH/higher CO2 does not inhibit photosynthesis. But instead of presenting evidence to refute my claims, Willard engages in deplorable wordsmithing to denigrate my well supported claim that increased CO2 does not inhibit photosynthesis. Innstead lower pH makes itCO2 more avaialable and minimizes the cost of pumping ions. Otherwise coral would not purposively reduce pH to the very acidic pH 4. And that is the topic that Willard wantonly tries to obfuscate.

      • > I did not report everything in the science literature. In other words I did not write an enycylopedia on the subject, I only wrote an essay.

        In that essay, we can read:

        Although in some species photosynthesis and calcification compete for bicarbonate ions, photosynthesis generally benefits calcification by providing energy, and by raising external pH, which lowers the cost of pumping internal H+ ions to the surrounding waters.

        The generality of that claim is a bit less general than what Jim claimed when we considered that up-regulation of pH, however, is not ubiquitous among calcifying organisms.

        ***

        > Yet my claim stands. Lower pH/higher CO2 does not inhibit photosynthesis.

        Jim’s thesis goes a bit beyond that:

        A combination of warmer tropical waters and coral reef biology results in out-gassing of CO2 from the ocean to the atmosphere, making coral reefs relatively insensitive to the effects of atmospheric CO2 on ocean pH.

      • Willard writes,

        Jim’s thesis goes a bit beyond that:

        A combination of warmer tropical waters and coral reef biology results in out-gassing of CO2 from the ocean to the atmosphere, making coral reefs relatively insensitive to the effects of atmospheric CO2 on ocean pH.

        So what’s Willard’s point???? Is Willard denying basic physics???

        Can Willard provide any scientific basis to show that in regions where coral reefs produce so much CO2 that it outgasses to the atmosphere, that atmospheric CO2 has any effect even though the laws of physics state that in such cases any diffusion of atmospheric Co2 into the ocean would be impossible?

        Why do internet snipers have such a deplorable understanding of basic science???

      • > Is Willard denying basic physics???

        So now coral reef biology is just basic physics.

        That’s just great.

        ***

        Meanwhile, research goes on:

        Marine macroalgae offer a feasible solution for reducing CO2 emissions by fixing CO2 as algal biomass and thus providing a source of renewable energy. The perennial red alga Palmaria palmata was cultivated and supplied with increased CO2 concentrations starting with 22 μmol kg−1 (pH 8.53) to 9770 μmol kg−1 (pH 6.04). Experiments covered test periods of 28 days, 7 days, and 2 h to examine the possible influence of different treatment durations. Biomass productivity over 28 days showed an increased production rate, which continuously declined with increasing CO2 concentration. After 7 days, the productivity was below the controls, suggesting a lag phase or necessary adaptation period to elevated CO2 concentrations of more than 7 days. Concerning the effects on maximum electron transport rate (ETRmax), light-harvesting efficiency (alpha), and light saturation of the photosynthetic electron transport (Ek), a stimulating influence was identified with the effect becoming more significant the shorter the test period was. The treatment with elevated CO2 concentrations for 28 days led to a decrease in photochemical efficiency (Y(II)) and regulated nonphotochemical energy dissipation (Y(NPQ)). In contrast, the treatment duration of 7 days predominantly increased photochemical quenching whereas the 2-h treatment resulted in a significant increase in photochemical quenching and in a significant decrease in nonregulated nonphotochemical energy dissipation. Hence, elevated CO2 concentrations over a prolonged time period interfered more distinctively with the fluorescence quenching ability of P. palmata.

        http://link.springer.com/article/10.1007/s10811-016-0939-8

        You’re welcome.

      • > denying basic physics???

        So now coral reef biology is just basic physics.

        That’s just great.

        ***

        Meanwhile, here’s the first hit on G Scholar for 2016:

        Marine macroalgae offer a feasible solution for reducing CO2 emissions by fixing CO2 as algal biomass and thus providing a source of renewable energy. The perennial red alga Palmaria palmata was cultivated and supplied with increased CO2 concentrations starting with 22 μmol kg−1 (pH 8.53) to 9770 μmol kg−1 (pH 6.04). Experiments covered test periods of 28 days, 7 days, and 2 h to examine the possible influence of different treatment durations. Biomass productivity over 28 days showed an increased production rate, which continuously declined with increasing CO2 concentration. After 7 days, the productivity was below the controls, suggesting a lag phase or necessary adaptation period to elevated CO2 concentrations of more than 7 days. Concerning the effects on maximum electron transport rate (ETRmax), light-harvesting efficiency (alpha), and light saturation of the photosynthetic electron transport (Ek), a stimulating influence was identified with the effect becoming more significant the shorter the test period was. The treatment with elevated CO2 concentrations for 28 days led to a decrease in photochemical efficiency [Etc.]

        You’re welcome.

      • The basic physics that Willard fails to comprehend is this.

        _Coral reefs are net producers of CO2 and that results in CO2 outgassing from that region.

        _There can be no net diffusion into the ocean if surface CO2 concentrations are higher than the atmosphere.

        _Thus coral reefs will be insensitive to atmospheric CO2

        That’s basic physics

    • “Rapidly rising levels of atmospheric CO2 are not only causing ocean warming,…” That statement brings to mind the old cliche about the tail wagging the dog.

  15. Mackey 2015 is a review paper — published in June 2015.

    In July 2015, this paper was published: Experimental design in ocean acidification research: problems and solutions by Christopher E. Cornwall and Catriona L. Hurd [ Cornwall and Hurd ICES J. Mar. Sci. http://dx.doi.org/10.1093/icesjms/fsv118 ; 2015 ] detailing the problems with OA studies to that date.

    The 6 August 2015 issue of the journal Nature carried a highlight article under the subject heading Ocean Acidification entitled “Seawater studies come up short — Experiments fail to predict size of acidification’s impact.” (.pdf of Nature article here)

    I wrote an essay on this issue and followed up with an essay based on Chris Cornwall’s response:

    Ocean Acidification: Trying to Get the Science Right

    Dr. Christopher Cornwall Responds to “Ocean Acidification: Trying to Get the Science Right”

    Basically, a lot of the science reviewed in Mackey 2015 is based on studies using inappropriate design resulting in results whose application to the real world are questionable for a variety of reasons.

    If you read my essay, read Cornwall’s response as well.

    • > If you read my essay, read Cornwall’s response as well.

      Thanks for this, Kip.

      The link in “Chris Cornwall responds to the Daily Mail here” leads nowhere, so it’s hard to see “some slight contradiction between his public statement and his published paper.”

      Chris cites this paper whose abstract ends thus:

      We demonstrate that red coralline algae respond differently to the rate and the magnitude of pH change induced by pCO2 enrichment. At low pH, coralline algae survived by increasing their calcification rates. However, when the change to low pH occurred at a fast rate we detected, using Raman spectroscopy, weaknesses in the calcite skeleton, with evidence of dissolution and molecular positional disorder. This suggests that, while coralline algae will continue to calcify, they may be structurally weakened, putting at risk the ecosystem services they provide. Notwithstanding evolutionary adaptation, the ability of coralline algae to cope with OA may thus be determined primarily by the rate, rather than magnitude, at which pCO2 enrichment occurs.

      http://onlinelibrary.wiley.com/doi/10.1111/gcb.12351/pdf

      Perhaps our bioenergetics gurus may take note.

      I’d be in favor of a Cochrane review of everything that appears at Judy’s.

      • The link in “Chris Cornwall responds to the Daily Mail here” leads nowhere, so it’s hard to see “some slight contradiction between his public statement and his published paper.”

        http://archive.senseaboutscience.org/resources.php/209/response-to-headline-quotbulk-of-research-on-impacts-of-ocean-acidification-is-flawedquot

        Chris cites this paper whose abstract ends thus:

        […] Notwithstanding evolutionary adaptation, the ability of coralline algae to cope with OA may thus be determined primarily by the rate, rather than magnitude, at which pCO2 enrichment occurs.

        A quick look at the linked paper shows that it fully supports his thesis:

        Red coralline marine algae were exposed for 80 days to one of three pH treatments: (i) current pH (control); (ii) low pH (7.7) representing OA change; and (iii) an abrupt drop to low pH (7.7) representing the higher rates of pH change observed at natural vent systems, in areas of upwelling and during CCS releases. We demonstrate that red coralline algae respond differently to the rate and the magnitude of pH change induced by pCO2 enrichment. At low pH, coralline algae survived by increasing their calcification rates. However, when the change to low pH occurred at a fast rate we detected, using Raman spectroscopy, weaknesses in the calcite skeleton, with evidence of dissolution and molecular positional disorder. [my bold]

        Neither of these scenarios has anything to do with multi-year increases of the sort posited for ocean acidification from anthropogenic CO2.

        Another squirrel from our local auditor serial distractionist.

      • willard ==> This link works for me:

        http://www.dailymail.co.uk/sciencetech/article-3187235/Are-climate-scientists-doom-mongering-Bulk-research-impacts-ocean-acidification-FLAWED-new-study-finds.html.

        Quotes from the Daily Mail:

        “However, a review of 465 studies into the effects of acidification on sealife said only 27 used an ‘appropriate experimental design’.

        And 278 studies were ‘clearly inappropriate’ which means a huge amount of research is not fit for purpose. Some of the research, if ‘reanalysed’, might yield useful data, but not in its current form, say the authors.
        ….
        The authors, commenting in Nature, say the ‘overwhelming evidence’ of ocean acidifiation still stands. But they say it is hard to assess the impact of ocean life from most of the experiments that have been carried out.”

        Note that Chris Cornwall was very helpful and informative, willing to communicate, provided a response to my essay and then subsequently answered additional questions from me. I posted his responses exactly as provided. There was absolutely no animosity at all.

        This is how science reporting should be done … a careful, well-rounded, fair report with a collegial response given equal treatment.

      • willard ==> You probably wanted the link provided by AK — to the Daily Mail piece: “Response to headline “Bulk of research on impacts of ocean acidification is FLAWED””.

        Here is Dr. Cornwall’s statement in its entirety:

        Dr Chris Cornwall, School of Earth and Environment, University of Western Australia

        “The article in the Daily Mail misrepresents our findings. There is overwhelming evidence that the effects of ocean acidification will impact our oceans through reductions in the growth and calcification rates of organisms with calcium carbonate ‘skeletons’ (e.g. shellfish, corals), and an alteration of the behaviour of other marine invertebrates and fish. We should be extremely worried about these future impacts of ocean acidification which will have irreversible consequences for our oceans. Rather than being “flawed”, the majority of ocean acidification studies have been carried out carefully, and provide extremely useful data on this complex area of research.”

        The “slight difference” can be seen between his original paper and his responses to my essay (and subsequent questions) regarding it and his response to the Daily Mail.

      • Indeed most of the calcification studies are flawed because that assume calcification is driven by carbonate ion concentrations. But no carbonate ion transporters have been found as discussed by researchers on the Omega Myth

      • @Kip Hansen…

        willard ==> You probably wanted the link provided by AK […]

        I doubt it. If he had wanted it he’d have chased it down himself. He knows how.

        IMO he was just “trying on” another squirrel. Probably hoping nobody who knew how to chase such things down would bother.

        Or perhaps he was just trying to waste people’s time. He does that a lot.

      • willard ==> If you want to discuss this, you absolutely must read Cornwall’s paper — all of it. It is about how this science on OA ought to be done, and how it wasn’t being done that way, resulting in a lot of studies that must be reanalyzed if we want to find the value in them. It isn’t just the “shock treatment” issue but the erroneous statistical approaches as well. Cornwall’s paper is very very clear as to the experimental design errors and the negative effect they had on findings — “… it is hard to assess the impact of [on] ocean life from most of the experiments that have been carried out.”

        Cornwall’s paper — highlighted in Nature — is a review of the quality of the science — covering the same studies reviewed (for the most part) by Mackey. His effort in the 2015 paper was to try to get the field back on the right track using appropriate design and methods so that reliable results — results that could be applied to the real world — could be obtained.

        It is nearly senseless to discuss Mackey 2015 without reference to Cornwall 2015 — of what practical use is a review study of science that has been showed to be seriously flawed without dissecting each study to take into account the faults and errors identified by Cornwall and Hurd?

      • From the guy who whines about squirrels, that’s just great.

        No squirrel of mine. The part you highlighted (and I left highlighted in my excerpt of your excerpt) conflicts with the part I highlighted in my excerpt of the abstract.

        Thus demonstrating its support for Kip’s thesis. And (as far as I can tell) Chris’s.

        If Kip and Chris are demonstrating how many papers report poorly designed experiments, and such papers make up a large part of Mackey et al. on which Jim bases some of his conclusions, then their subject is relevant.

        But given that the Kamenos et al. paper you cited was not cited by Mackey et al., that would make it a squirrel.

        Of course, it would be easy to find issues with Mackey et al., except to demonstrate the crying need for more and better research.

        Better research should (IMO) include a better real-world framing, distinguishing between increased pCO2 and OA, noting the transient and seasonal effects of calcification and photosynthesis and their interactions with longer-termed ocean/air equilibration, allowing for short-term evolutionary adaptation, etc.

        As with climate, today’s research establishment lacks the data, analytical tools, and (probably) computational power to make credible predictions.

        Which doesn’t mean there’s no risk. We just don’t have any way of determining how much.

      • > It is about how this science on OA ought to be done, and how it wasn’t being done that way, resulting in a lot of studies that must be reanalyzed if we want to find the value in them.

        None of this implies that everything is “flawed” like the Daily Fail asserted or that there is the “slight difference” you only insinuate, Kip.

  16. “The superheated water is at temperature from 60°C up to over 450°C and because of the high pressures at depths the water has physical properties between a gas and a liquid. The water is also extremely acidic, often having a pH value under 3.0, similar to vinegar.”

    Good thing the vast expanses of abyssal corals can manage, isn’t it? They survive down to about -1 C (according to the Smithsonian Ocean Portal). There are unknown numbers of undersea vents, pushing an unknown quantity of heat, CO2 and all sorts of other chemicals into the oceans.

    Man’s puny efforts to restore the balance of Nature by burning the fossilised plant remains sequestered by Nature in eons past, might help to stave off Man’s extinction for a while. I certainly hope so.

    Cheers.

  17. Willard stop avoiding the fact that you have misrepresented many issues. We are still waiting for you to list the papers that show unequivocably that rising CO2 has inhibited photosynthesis.

    • > We are still waiting for you to list the papers that show unequivocably that rising CO2 has inhibited photosynthesis.

      There’s no need to do so to show that Jim’s own citations undermine his thesis that coral reefs are relatively insensitive to the effects of atmospheric CO2 on ocean pH.

      The very concept of “relative insensitivity” might even go against the holism put forward by Gaia theory.

      • Another dishonest dodge by Willard. He fails to show any evidence that rising CO2 had inhibited photosynthesis while continuing to dishonestly suggest the papers I have cited undermine my claim: rising CO2 has not inhibited photosynthesis. One must wonder that with such blatant dishonest, how Willard lives with himself.

      • Another 2016 hit:

        Studies on the long-term responses of marine phytoplankton to ongoing ocean acidification (OA) are appearing rapidly in the literature. However, only a few of these have investigated diatoms, which is disproportionate to their contribution to global primary production. Here we show that a population of the model diatom Phaeodactylum tricornutum, after growing under elevated CO2 (1000 μatm, HCL, pHT: 7.70) for 1860 generations, showed significant differences in photosynthesis and growth from a population maintained in ambient CO2 and then transferred to elevated CO2 for 20 generations (HC). The HCL population had lower mitochondrial respiration, than did the control population maintained in ambient CO2 (400 μatm, LCL, pHT: 8.02) for 1860 generations. Although the cells had higher respiratory carbon loss within 20 generations under the elevated CO2, being consistent to previous findings, they downregulated their respiration to sustain their growth in longer duration under the OA condition. Responses of phytoplankton to OA may depend on the timescale for which they are exposed due to fluctuations in physiological traits over time. [Etc.]

        http://onlinelibrary.wiley.com/doi/10.1111/gcb.13501/full

        Again, we see that timescale matters.

      • Willard fails to support his and Mosher ‘s dishonest assertion that I mispresented Mackey. So he googles for papers that might show high CO2 inhibits photosynthesis, but he does not analyze the paper critically and reveals he is not a scientist. NOr someone who is capable of critically analyzing a scientific paper.

        First the paper’s methods are flawed in the sense that both the control (LCL at 400 ppm) and experimental (HCL 1000 ppm) remained constant. In reality biologically controlled CO2 changes daily and pH flucuates daily between about pH 8.4 and 7.7.

        Willard fails to report the paper’s result that “growth rates ranged between 0.96 ± 0.11 and 1.50 ± 0.01 d−1 in both LCL and HCL populations over the entire experiment.” Rates of 1 were considered normal thus growth rates in both treatments experienced dips by only 4% but increases of up to 50%.

        To maintain the same density of cells in their experimental bottles the growing algae were constantly diluted. This creates a selective pressure that can result in genetic drift. Genetic drift has been observed in organisms after 100 generations and this experiment endured for 1860 generations.

        Under high CO2 there were generations that exhibited higher growth rates. Only after generations from 960 to 1035, did they observe “a 10% decrease in growth rate of HCL relative to the LCL population”

        The lack of any significant long term effect at a constant 1000 ppm CO2 for 959 generations, and only then a sudden 10% decrease in growth rate suggests the dilution protocol resulted in genetically different strains that confound any reasonable evaluation of CO2 effects on generations 960 and beyond.

      • WIllard links above to a study on Phaeodactylum tricornutum that I show used faulty methodology to reach in meaningful conclusions, yet none the less showed no ill effects from high (1000 ppm) CO2 for 950 generations

        Here is what Mackey reports about this same species

        P. tricornutum takes up CO2 preferentially over HCO3– from seawater(Burkhardt et al., 2001; Cassar et al., 2006); thus, one would expect a pronounced response in photosynthetic C fixation under enhanced CO2. However, studies have provided different findings. Under enhanced CO2, Phaeodactylum shows increased photosynthetic electron transport rates, but no change or very modest increases in growth (5–13%; Wu et al., 2010; Li et al., 2014) or C fixation (Burkhardt et al., 2001). Even at very high CO2 concentrations (5,000 ppm), photosynthesis was not stimulated (Matsudaet al., 2011). The CCM of this species is down-regulated under high CO2, showing lower cellular affinities for inorganic carbon (Burkhardt et al., 2001; Wu et al., 2012; Li et al., 2014). This could potentially save energy to fuel other metabolic processes but may result in the loss of photoprotection.

        This is one of the examples cited in Mackey’s review (but not mentioned in the abstract) showing marine photosynthesizers down regulate their carbon concentrating mechanisms as CO2 becomes more available. Thus studies that measure photosynthetic rates in response to increased CO2, will show only minor stimulation. But as I have argued in this essay, a lower pH and higher CO2 reduces the energy required to transport bicarbonate ions. And to show that benefit of lower pH that ” could potentially save energy ” studies need to be designed to measure the bioenergetics. Very few have done so.

        And again even at 5000 ppm they make no mention of inhibited photosynthesis.

      • Willard you were challenged over and over to supply a list from Mackey that showed higher CO2 inhibited photosynthesis and to support your slanderous sniping I had misrepresented Mackey’s review. ANd you still have avoided doing that because the paper’s content was only butchered by you and Mosher.

        You say I have moved the goal posts. ROTFLMAO The goalpost are still what are the effects of rising CO2 on photosynthesis. Because it was clear that you tried to throw out a link for a paper that only in the remotest terms suggested an inhibitory effect and was flawed, does not mean I moved the goal posts of striving for accurate science. It means you do not read scientifically papers critically. It shows you have no science background as you would admit. And shows you are only interested in discursive word play.

    • Since Willard fails to comprehend what Mackey reviewed and ignores it, let me repeat the evidence Mackey discussed

      _ Photosynthesis in Prochlorococcus was unresponsive to pCO2

      _Elevated CO2 caused higher phycobilin and chlorophyll-a content in Synechococcus, leading to a higher
      light harvesting efficiency (α) and a lower light saturation constant (Ek). High CO2 alone did not increase maximal photosynthetic rates in this strain; however, when high CO2 was combined with a warmer temperature (4°C above the control), maximal photosynthetic rates increased twofold relative to elevated temperature alone.

      _At least one genus of picoeukaryotes (Ostreococcus) appears to be strongly enhanced by elevated CO2, with growth rates almost doubling at 1,000 ppm (Schaum et al., 2013).

      _(Regards diazotrophic/ nitrogen fixing plankton) To date, almost all studies suggest that N2 fixation will increase in response to enhanced CO2

      _T. pseudonana [a diatom] showed an increased maximum photosynthetic rate (Pmax) and an increased PE curve halfsaturation constant (Ek) under high CO2, suggesting that more light was required to saturate photosynthesis (Sobrino et al., 2008). Growth rate also increased by 20% under high CO2 in this experiment

      _Under enhanced CO2, Phaeodactylum [diatom} shows increased photosynthetic electron transport rates, but no change or very modest increases in growth
      or C fixation

      _A mesocosm experiment conducted in Bergen, Norway, reported that net community carbon consumption and net photosynthesis increased under increased CO2 for a mixed community of diatoms and coccolithophores (Riebesell et al., 2004). In a later mesocosm study with a different initial community composition, diatoms were outcompeted at high CO2 while picoplankton were strongly stimulated (Riebesell et al., 2013). A third mesocosm experiment with two different diatom species (Skeletonema costatum and Nitzschia spp.) under nutrient replete conditions showed that only S. costatum increased growth rate under enhanced CO2 (Kim et al., 2006). Therefore, the effect of enhanced CO2 on natural diatom populations depends on the species of diatoms, as well as on the overall composition of the phytoplankton community.

      _Coccolithophores appear to rely primarily on aqueous CO2 for photosynthesis, while preferring to access HCO3 – for calcification (Buitenhuis et al., 1999; Bach et al., 2013). Consequently, rising CO2 tends to promote photosynthesis over calcification and reduce the ratio of inorganic to organic carbon in these organisms

      _found that photosynthesis and growth in most species were not C saturated under present-day CO2 concentrations. Because C3 photosynthesis is more sensitive to the direct effects of CO2 concentration, future increases in CO2 will most likely increase photosynthetic rates and growth in marine macrophytes,

  18. The entire ocean acidification argument is for me another piece of evidence that the threats to our planet or survival from increasing concentrations of CO2 are far more hype based than science based.

  19. Reblogged this on 4timesayear's Blog.

  20. Thanks, Jim, for this post. You seem to have stuck a nerve in the stauch believers of absolutely fearful global climate change. Congratulations.

  21. Wow, what a weak comment thread for a post with such huge implications.

    • Agreed. I hoped for more meqningful discussion, but Willard and Mosher’s dishonest empty assertions and their effort to hijack the thread via their obsessive misunderstanding of the Mackey paper was purposely disruptive.

  22. Geoff Sherrington

    Rhyzotika,
    Sadly the comments have not been as strong as they might.
    To me, the processes went roughly.
    1. There was long time general agreement that marine biota would respond with increased yield to fertilization (in the nutrient sense) if a particular nutrient was low and yield was not otherwise limited.
    2. Activism postulated that CO2 was bad for everything, that ocean acidification was evil, that CO2 would kill marine life and precipitate emergencies, maybe it was not even a nutrient.
    3. Some activist papers claimed marine biota damage from extra CO2, though many were inconclusive or others criticised for inappropriate experimental design. Recall that even the measurement of pH in the ocean is devilish hard, see e.g. Debye-Huckel equation.
    4. For many it became an accepted belief that the weight rate of CO2 going into oceans from the air had to be reduced. No matter that how it was being sequestered/exuded on land and in sea were poorly understood.
    5. In present context, Mackey published in a review that there were examples of CO2 fertilized growth of marine biota, none or indistinct cases of yield lost with more CO2, lots of ‘depends on’ interpretations.
    6. Jim Steel published the blog essay above, quoting Mackey, with the overall message that on review, CO2 seemed more good than bad for marine biota studied.
    7. A dissenter W…. something, whose words I have ceased to read, tried to hijack the thread and argument using inter alia slants on quotes by Mackey.
    8. This seems to have discouraged more comments here, though it is hard to tell.

    Meanwhile, irrespective of what is opined, Physics and Chemistry will continue on their courses, plausibly revealing a better understanding over time. But the trend of scientific thought is now towards ocean acidification not being the bogey man.

    Note to Jim. Thank you for the Chemistry and more, but no need to invoke Gaia. Religious connotations often sidetrack.
    Geoff

  23. Inese Poga Art plus Life

    All changes, both positive and negative, only show how the Earth is trying to maintain homeostasis. Without being in balance, any existence is disturbed. Extremely insightful and scientifically proven post.
    I’d be happy you had a look at my secondary blog https://inesepogalifeschool.com/
    I do not feel I have to attach measurements or fact sheets, but I am trying to popularize the idea of living in balance with nature and doing as little harm as possible.

  24. Thank you for the most interesting article.
    Proofreading: there seems to be some mistake in the first link to Marañón et al.
    http://onlinelibrary.wiley.com/doi/10.1002/lno.10295/abstract

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  27. Jim Steele,
    Thank you for writing this very interesting article and posting it here.

  28. OK so I’ll try to push the discussion out one level.

    One thing cool about this post is it links the Ocean Acidification thing to the carbon mass balance, “cyling of carbon”, and strongly supports (maybe not definitively proves) that biotic activity is a driver of ocean chemistry, not just a passive recipient of forcings or whatever.

    It makes me think of Bart’s arguments about how carbon sinks are dynamic – how they can keep expanding with inputs. And how those sinks can be relatively invisible. (And that doesn’t even go to the question of to what degree phytoplankton radiolaria & other ocean-going microbes might be communicating and coordinating their activites, whether via swapping DNA bits or or other kinds of chemical interaction.)

    Also there were a couple hints in Jim’s post about how buried carbon/CO2 in different forms can well back up from thousands of years ago – though I don’t think supporting papers or links were provided. This is a difficult or impossible to measure potential source of CO2 that could potentially be feeding into the Keeling Curve – massive, gradual, long-term. Of course that’s still speculative – but is it any more speculative than saying “80% of the warming went into the the deep ocean where we can’t actually measure it”. OK I’ll probably be shot down by folks that know more, but those are the interesting implications, to me, of this post.

    BTW did anybody see this about microbial life

    And here is one of Lovelock’s disciplines Andrew Watson discoursing on the natural variability of anoxic events (based on paper with another Lovelockian Tim Lenton) – phosphorous positive feedback loops in geological time; could be exacerbated by industrial phosphorous runoffs triggering or extending an Anoxic Event. No charts :(
    [audio src="http://downloads.royalsociety.org/events/2016/09/ocean-ventilation/Andrew-watson.mp3" /]

    And this too – video from SciAm – “Life Blooms in the Clouds” https://www.scientificamerican.com/video/clouds-final1080-external-d-mp4/
    Also hard to measure, & therefore model…?

    • Some of the issues about carbon stores in the ocean are touched upon in the del Giorgio paper “Respiration in the open ocean.”

      Also do you have a link to Bart’s “dynamic feedback CO2” model?

      • Jim, thanks for that, will look up.

        Re Bart there are many posts both here and on WUWT where (mainly) Bart and Ferdinand Engelbeen go back and forth about the carbon mass balance thing. Bart actually puts the nonlinear math formulas on the table for what he’s describing. Unfortunately Bart has never written a dedicated post, at least that I’ve seen anywhere. Still waiting…

  29. Jim, here is the start of one of those debates between Bart/Bartemis and Engelbeen (& others – but those 2 in particular have been pursuing this debate ad nauseum across multiple posts here and @ WUWT)
    https://judithcurry.com/2015/05/06/quantifying-the-anthropogenic-contribution-to-atmospheric-co2/#comment-701168

  30. BTW there’s a downloadable pdf here for anyone else re Open Ocean Respiration
    https://www.researchgate.net/publication/11010353_Respiration_in_the_open_ocean

  31. “After all, we cannot claim to grasp the global carbon cycle when we do not know whether the biota of theworld’s oceans is a net source or sink for carbon.” https://www.researchgate.net/publication/11010353_Respiration_in_the_open_ocean

  32. Did you know that the world’s oceans are chemically buffered? Every second of ever day of every year, dissolved minerals are delivered into the oceans by way of the “fresh water” rivers inflows. These minerals eventually precipitate out of the seawater forming nodules on the ocean floor. These nodules gradually grow over time (geological time). If the oceans become more basic, more minerals precipitate out. If the oceans become more acidic, fewer minerals precipitate out.

    The nodules are primarily made up of manganese and iron. I did a paper in 4th year describing the options for recovering these mineral deposits from the ocean floor. It is expensive compared to traditional dry land methods facing many of the same challenges for recovering methane hydrates from the oceans. There are also law of the sea and environmental concerns that limit economic viability.

  33. Jeff, the state of ocean pH due dissolved mineral was discussed in the link to the Cohen and Happer article
    http://co2coalition.org/wp-content/uploads/2015/12/pH.pdf ,
    under the subsection pH in a lifeless ocean.

    Without CO2’s buffering effect the oceans would have a much higher pH and that would make photosynthesizing even more difficult.

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  35. Jim Steele ==> You might have missed this paper:

    High-Frequency Dynamics of Ocean pH: A Multi-Ecosystem Comparison
    Hofmann GE, Smith JE, Johnson KS, Send U, Levin LA, et al.

    Kenneth S. Johnson (Monterey Bay Aquarium Research Institute), in whose lab the Deep-Sea DuraFET sensor was designed/developed for use on ARGO-type floats, sent me the cite when I asked him about the accuracy/sensitivity of ARGO pH data.

    Data on calibration and accuracy/precision is available in this paper (of which Johnson is a co-author):

    Testing the Honeywell Durafet® for seawater pH applications

    Todd R. Martz, James G. Connery, and Kenneth S. Johnson

    Links are to freely available .pdfs.

    • Hi Kip,
      I am aware of the paper and used some of their graphs in a segment of my IEEE presentation that covered ocean acidification claims.

      I was unaware of the paper Testing the Honeywell Durafet® for seawater pH applications. Thanks.

      I did not include the Hofmann paper (and many others) in part because the essay was already lengthy. It was valuable in showing the tremendous variability of pH at different sites, yet did not go into much depth about the mechanisms causing pH variability.

      In this essay I wanted to show the biological needs and effects relating to pH. The higher pH goes above 8.1 the more costly is ion pumping needed for photosynthesis. Papers pushing “ocean acidifiction” catastrophes focus on calcification but 1) calcification is tightly linked to photosynthesis and 2) increasing pH to increase carbonate ions is not needed because organisms import bicarbonate ions.

      • Jim ==> The Hoffman paper didn’t make a very big splash, so thought it might have gone unnoticed. It is both very interesting and very important — the closest thing to some actual real dependable measurements of ocean pH.

        I forgot to give you this link to the data visualization page provided by Ken Johnson:

        http://www.mbari.org/science/upper-ocean-systems/chemical-sensor-group/floatviz/

        Not all the floats have pH sensors, the codes are t the bottom of the page.

        Using “all dates available”, pH, and depth gives a fat line graph that indicates both the long-term variation and variation by depth. The difference between Raw and Adjusted narrows the “fat line” a bit.

  36. Jim, Willard is doubly upset at the paper by Matt Ridley showing a 14% increase in greening of the world due to rising CO2.
    It would seem hard to say that it is only the land plants that have increased due to the rise in CO2.
    Willard enjoys the art of distraction by misrepresenting the gist of your argument.
    Hence he will never answer your request to him.
    Never.
    Mosher is playing tag with him here.
    Safest way to deal with him, and the one he will find the most annoying here is a blanket “answer the question first, Willard”.
    This is standard technique and very satisfying when you are in charge of running the blog in question.
    Best of luck.

    • Thanks angech.

      It quickly became quite clear Willard and Mosher will never “answer the question” first. If they did it would show they were disgustingly dishonest and that they were only trying obfuscate the science I presented.