2011-01-10 17:19:34Ocean Acidification Isn't Serious - New Rebuttal Commissioned by John Cook
alan_marshall

alan.from.tas@gmail...
58.172.60.30

 

What the Science Says:

The current debate on the connection between CO2 emissions and climate change has largely overlooked an independent and equally serious problem, the increasing acidity of our oceans. Last December, the respected journal “Oceanography” published projections (see graphic below) for this rising acidity, measured by falling pH [i], through to the end of the century [ii]. For 2095, the projected average ocean surface pH is about 7.8, and lower still in the Arctic Ocean.

CO2 in the atmosphere has increased from 278 ppm in pre-industrial times to 390 ppm today. During this time, the amount of CO2 dissolved in the ocean has risen by more than 30%, decreasing the pH of the ocean by 0.11 units. As with CO2 and global warming, there is a lag between cause and effect. That means we are yet to see the worst of the problem. According to the Australian Antarctic Division of our Department of the Environment, “even if all carbon emissions stopped today, we are committed to a further drop of 0.1 to 0.2 pH units[iii]. .

The close relationship between CO2 in the atmosphere, CO2 dissolved in the ocean, and the effect of the latter in falling pH, is illustrated by the graph [iv] below:

The chemistry of ocean acidification is simple. CO2 dissolves in water to form carbonic acid. (It is worth noting that carbonic acid is what eats out limestone caves from our mountains.) In the oceans, carbonic acid releases hydrogen ions (H+), reducing pH, and bicarbonate ions (HCO3-).

CO2 + H2O => H+ + HCO3-   (1)

The additional hydrogen ions released by carbonic acid bind to carbonate ions (CO32-) to form additional HCO3-.

H+ + CO32- => HCO3-   (2)

The two main forms of calcium carbonate used by marine creatures are aragonite and calcite. Decreasing the amount of carbonate ions in the water therefore makes it harder for both aragonite users such as corals and shellfish, and calcite users such as foraminifera, to build their exoskeletons.

The implications of all of this are frightening. For corals to absorb aragonite from seawater, the latter needs to be saturated in this mineral. Now a report from NOAA scientists found large quantities of water undersaturated in aragonite are already upwelling close to the Pacific continental shelf from Vancouver to northern California [v]. Although the study only dealt with the area, the authors suggest that other shelf areas may be experiencing similar effects.

It is often said that a picture is worth a thousand words. In the Southern Ocean, there is grave evidence of harm to foraminifera. Even though these creatures use calcite, which is less soluble than aragonite, there are already clear signs of physical damage.

        

According to Dr Will Howard of the Antarctic Climate and Ecosystems Cooperative Research Centre in Hobart, shells of one species of foraminifera (Globigerina Bulloides) are 30 to 35 percent thinner than shells formed prior to the industrial period [vi]. The photo above left shows a pre-industrial  exoskeleton of this species obtained from sea-floor sediment. The photo above right shows a exoskeleton of a live specimen of the same species obtained from the water column in the same area in 2007. These stunning images were obtained by Dr Howard using an electron microscope. (An interview with Dr Howard was broadcast on the Catalyst television program). [vii] These and creatures like them are at the base of an ocean food chain, and they are already seriously damaged. If they are lost, it is not just biodiversity we are loosing, but our food supply as well.

For corals like those in Australia’s Great Barrier Reef, the outlook is grim. They are threatened with destruction on two fronts, both caused by CO2 emissions. Not only do increased ocean temperatures bleach coral by forcing them to expel the algae which supplies them with energy (see photo below) [viii], but increased ocean CO2 reduces the availability of aragonite from which reefs are made.

It is time to wake up. Our planet is dying. I urge you to find the time to view a 20 minute documentary on the problem of ocean acidification produced by the international Natural Resource Defence Council. Simply go to www.acidtestmovie.com.




References and Notes

[i]  pH is a measure of the acidity or alkalinity of a solution. It uses a negative logarithmic scale where a decrease of 1.0 units represents a 10-fold increase in acidity. In their natural state prior to industrialization, the oceans were slightly alkaline with a pH of 8.2 (see reference iii). Pure water has a pH of 7.0.

[iii]  Feely R., Doney, S., Cooley S. (2009).Present Conditions and Future Changes in a High-CO2 World , Oceanography 22, 36-47

[iii]  Australian Antarctic Division, Ocean Acidification and the Southern Ocean, available at www.aad.gov.au/default.asp?casid=33583

[iii]  Feely, Doney and Cooley, op. cit, using Mauna Loa data from the US National Oceanic and Atmospheric Administration and Aloha data from the University of Hawaii.

[v] Feely R., Sabine CL, Hernandez-Ayon JM, Ianson D, Hales B (June 2008). Evidence for upwelling of corrosive "acidified" water onto the continental shelf. Science 320 (5882): 1490–2, available at http://www.sciencemag.org/content/320/5882/1490

[vi] Inter Press Service, Acid Oceans Altering Marine Life, available at http://ipsnews.net/news.asp?idnews=46055

[vii] Australian Broadcasting Corporation, Ocean Acidification – The Big Global Warming Story, downloadable at http://www.abc.net.au/catalyst/stories/s2029333.htm

[viii]  Great Barrier Reef Marine Park Authority, What is Coral Bleaching?, available at http://www.gbrmpa.gov.au/corp_site/key_issues/climate_change/climate_change_and_the_great_barrier_reef/what_is_coral_bleaching

2011-01-11 17:24:45
Glenn Tamblyn

glenn@thefoodgallery.com...
124.180.254.187

Alan

 

Good piece. Some extra detail. You use 'the increasing acidity of our oceans' at the top, making it sound like the oceans are already acidic and becoming more so. Perhaps 'the increasing acidification of our oceans' - its splitting hairs but the black hats will do that.

Perhaps some elaboration on the chemistry. Reading it currently it isn't clear that you are describing how the carbonate chemistry of the oceans changes as distinct from what the chemistry is. Wiki has a good piece on Ocean Acidification including a graph of CO2, Carbonate and Bicarbonate vs ph. This shows the proprtions of each changing and then you could explain that this is driven by the need to keep the oceans electrically neutral as hydrogen ions are being added.

Also perhaps, that the rate at which CO2 is being added to the oceans means that ocean mixing can't transport this to the deeps fast enough so the changes are being magnified in the surface levels where most life lives.

Next, the emphasis is often given to the effect on corals in articles about this, but I don't think that is the most important impact. Corals matter (over and above our aesthetic attachment to them) because they are important centres for biodiversity and as nursery areas for many species. But they only occupy a small fraction of the oceans. Most of the ocean is the open ocean in which corals don't grow. However many of the other species you mention are all part of the base of the food chain and support the whole food web in the ocean. This is potentially a bigger impact than the threat to corals. Parrticularly when it is considered in conjunction with other threats to the marine food chain - continuing declines in fish stocks in many fisheries and the threat of warmer waters expanding the regions that are dead zones - waters that are oxygen depleted because they are to warm. There is a reason the tropical oceans are often crystal clear - not much lives in them.

So acidification isn't just a threat to things we might want to preserve for other reasons. Its a threat to human food supply!

2011-01-12 17:15:28
alan_marshall

alan.from.tas@gmail...
58.172.60.30
Glenn,

Thank you for your input. All feedback will be considered when I write the final version. 

I agree with your comments on the chemistry. In fact, I use the graph that you mention, along with 4 equations, in the advanced version. Working on intermediate and advanced versions simultaneously, there is a need to graduate the content, and it is possible material may move back and forth before the final versions are posted. I also have written a basic version, but am not posting it at this stage.

Coral reefs are second only to rainforests when it comes to biodiversity, so they do matter. However, I also agree with you that the impact of ocean acidification on microscopic life is just as worrying. In between the two paragraphs on corals, the above article contains an equal amount of information on foraminifera. The blue close-up images are foraminifera Globigerina Bulloides. Extensive depletion of CaCO3 is clearly visible in the right sample, collected in 2007.

I will look into the other points that you raise.
2011-01-13 06:46:08
Rob Painting
Rob
paintingskeri@vodafone.co...
118.93.208.34

Al, what are the two blue pictures side-by-side showing?. It's not obvious in the rebuttal.

Thought I had bookmarked a sequence of photos from a study that simulated pH conditions from pre-industrial to later this century, and it's effects on mussel growth. The decline in size was striking, even from pre-industrial to today. Only glossed over it and now can't find it. Do you know the study I'm referring to?. IIRC it would great to include in your piece.  

2011-01-16 14:40:53
alan_marshall

alan.from.tas@gmail...
58.172.60.30

Rob,

If you have also been confused about these images, I had better label them. As explained in the text below the images, they are electron microscope photographs of the foraminifera Globigerina Bulloides, showing the before and after effects of the lower pH now experienced in the Southern Ocean. They were shown on the science program “Catalyst” which screened on Australian television in September 2007 (www.abc.net.au/catalyst/stories/s2029333.htm). The program reported that this was the first proof that marine creatures were already being damaged by ocean acidification. I find the images much more shocking than the simulation of damage projected to occur to calcifying phytoplankton by the end of the century (www.ocean-acidification.net/FAQeco.html). With proof that the shells of some foraminifera are already depleted by 30 to 35 percent as a result of excess CO2, the writing is on the wall for the skeptics.

I haven’t seen the simulation you refer to which predicts reduced mussel growth.

 

2011-01-16 18:35:25
Rob Painting
Rob
paintingskeri@vodafone.co...
118.92.76.234

Al, I was thinking more for the readers benefit that's all. It's all too easy to forget that the target audience will know next to bugger all about these things, and those are the people we need to convince.

The mussel study I can't find yet, but the decline in growth between pre-industrial ph conditions and today was surprising. When I saw it I thought that it would be a great image for the OA rebuttal, as it would obvious to every man and his dog the effect we're having on marine inhabitants. Apparently I didn't bookmark it, but will keep looking. 

2011-01-16 22:15:14
nealjking

nealjking@gmail...
91.33.115.143

alan,

I stared at those photos for awhile, too. To the untrained eye (me), the differences seemed very subtle. The text would be improved by saying something like, "Notice how (this feature) on the left is (bigger/smaller/thinner) than (that feature) on the right. This means.."

2011-01-21 11:08:42
alan_marshall

alan.from.tas@gmail...
58.172.60.30

Neal, Rob

Thanks for the feedback. Clearly, I need to spell out the changes in the right hand image. The difference is the number of holes, and it is not subtle. If I can explain this adequately, it is actually quite shocking. The fact that the magnification of the right hand image from the Catalyst program is apparently 2 to3 times the left image doesn't help. I have permission to use the images from Catalyst, but I will need to get some software to capture individual frames from video, and play around with the sizing, to correct this. If you can cope with the difference in magnification for the moment, you will notice there are over 100 holes in the right image, around 10 times the number in the left image. The exoskeleton of the 2007 sample of this foraminifera is porous. It has been "white-anted" by a changed ocean chemistry which does not allow it it replace calcite at the speed at which it is dissolved. How much more erosion can these creatures withstand? (For further details on what marine life uses calcite, and what uses aragonite, see my draft for the advanced rebuttal).

2011-01-21 12:23:59"Subtle" is in the eye of the beholder...
nealjking

nealjking@gmail...
84.151.29.125

I didn't even notice the holes. I just had the impression that the right-hand side was a little rougher than the left-hand side.

=> People need to be trained to see what looks "obvious" to someone familiar with the field.

2011-01-21 15:58:19Ocean Acidification: The Untold Stories
John Hartz
John Hartz
john.hartz@hotmail...
98.122.68.19

If you have not already done so, you should check out:

“Ocean Acidification: The Untold Stories” published by Oceana. It is chocked full of marvelous photos.

http://na.oceana.org/sites/default/files/reports/Ocean_Acidification_The_Untold_Stories.pdf

2011-01-22 11:22:41
Shirley_Rocks
Shirley Pulawski
missfabulous@verizon...
96.240.83.234

I like it, generally but it needs some fine-tuning.

- typo in 3rd to last paragraph - 'losing" has only one 'o' not two.  

- I would reconsider the use of the word "frightening" and instead use something less emotion-based, like "very significant" simply because that could set off a bell for those who like to call us "alarmists" or as pushing fear to drive an agenda. 

 - Get rid of the words "grim" "grave" and "stunning" for the same reason.  Significant, substantial, material, consequential, etc. are less "alarmist" to those types who see us in that light. How about something like:

Survival of corals like those in Australia’s Great Barrier Reef will be hampered as conditions continue to deteriorate. (Instead of "For corals like those in Australia’s Great Barrier Reef, the outlook is grim")

The implications of acidification are quite significant. (Instead of "The implications of all of this are frightening.")

Research in the Southern Ocean provides evidence that the formation of foraminifera shells is already being affected. (Instead of "In the Southern Ocean, there is grave evidence of harm to foraminifera.") 

 - For the same reasoning, I would rewrite the last paragraph completely, and it comes across as editorializing. Just provide the link with a brief explanation of what it is and who produced it.

 - The abbreviation "Dr" needs a period after it in each case - "Dr." not "Dr" 

 -  Get rid of "It is often said that a picture is worth a thousand words." It's cliche and doesn't provide any information. 

2011-03-07 13:30:18Ocean Acidification Isn't Serious: Second Draft of New Intermediate Rebuttal
alan_marshall

alan.from.tas@gmail...
58.169.133.244

What the Science Says:

The current debate   on the connection between CO2   emissions and climate change has largely overlooked an independent and equally   serious problem, the increasing acidity of our oceans. Last December, the respected   journal “Oceanography” published projections (see graphic below) for this rising   acidity, measured by falling pH [i],   through to the end of the century [ii]. 

Fig   1: Ocean surface pH - historical values and projected future values based on   current emission projections.
  

  

CO2 in the atmosphere   has increased from 278 ppm in pre-industrial times   to 390 ppm today. During this time, the amount of   CO2 dissolved in the ocean has   risen by more than 30%, decreasing the pH of the ocean by 0.11 units. As with   CO2 and global warming, there   is a lag between cause and effect. That means we are yet to see the worst   of the problem. According to the Australian Antarctic Division of our Department   of the Environment, “even if all carbon emissions stopped today, we are   committed to a further drop of 0.1 to 0.2 pH units[iii]. However,   if CO2   is allowed to rise along a business as usual trajectory,   they are concerned that pH will “fall by 0.5 pH units by 2100, a 320% increase   in acidity”.

The   close relationship between CO2   in the atmosphere, CO2   dissolved in the ocean, and the effect of the latter in falling pH, is illustrated   by the graph [iv] below:

Fig   2: Annual variations in atmospheric CO2,   oceanic CO2, and ocean surface   pH. Strong trend lines for rising CO2   and falling pH.

The chemistry   of ocean acidification is simple. CO2   dissolves in water to form   carbonic acid. (It is worth noting that carbonic acid is what eats out limestone   caves from our mountains.) In the oceans, carbonic acid   releases hydrogen ions (H+), reducing pH, and bicarbonate ions (HCO3-).

CO2 + H2O => H+ + HCO3-     (1)

The additional hydrogen ions released by carbonic acid bind to carbonate   ions (CO32-), forming additional HCO3-.   

H+ + CO32- => HCO3-     (2)

This reduces the concentration of CO32-, making   it harder for marine creatures to take up CO32- to form the calcium carbonate needed   to build their exoskeletons.

Ca2+ + CO32- =>   CaCO3   (3)

The two main forms of calcium carbonate used by marine creatures   are calcite and aragonite. Decreasing the amount of carbonate ions in the water   makes conditions more difficult for both calcite users (phytoplankton,   foraminifera and coccolithophore algae), and aragonite users (corals, shellfish, pteropods and heteropods). The   photo below left shows healthy phytoplankton. The photo below right shows the   damage to the same creature under conditions expected by the end of the century   (see Fig. 1).

         

   

Fig 3: Healthy phytoplankton;     same species damaged by seawater with simulated end of century chemistry.
    
Source: Nature,     Reduced Calcification of Marine Phytoplankton in Response to Increased     Atmospheric CO2, Issue 407 p.364 -367
    

It is often said that a picture   is worth a thousand words. Research in the Southern   Ocean provides evidence that the formation of foraminifera shells is already   being affected. Even though these creatures use calcite, which is less soluble   than aragonite, there are already clear signs of physical damage. According to Dr. Will   Howard of the Antarctic Climate and Ecosystems Cooperative Research Centre in   Hobart, shells of one species of foraminifera (Globigerina Bulloides)   are 30 to 35 percent thinner than shells formed prior to the industrial period [vi]. The photo below left shows a   pre-industrial  exoskeleton of this species obtained from sea-floor sediment.   The photo below right shows a exoskeleton of a live specimen of the same species obtained   from the water column in the same area in 2007. These stunning images were obtained   using an electron microscope. (An interview with Dr. Howard was broadcast on   the Catalyst television program). [vii]   What is staggering is the amount of erosion in the right image compared to the   left. The right sample look porous with larger holes and a 10-fold increase   in their number. These and creatures like them are at the base of an ocean food   chain, and they are already seriously damaged. If they are lost, it is not just   biodiversity we are losing, but our food supply as well.

            

Fig 4. Pre-industrial and   current samples of Globigerina Bulloides from same location.   Latter shows extensive erosion with a ten-fold increase in holes.
  
Source: Australian   Broadcasting Corporation, Ocean Acidification – The Big Global Warming Story,   13 September 2007

The implications   of all of this are disturbing. For corals to absorb aragonite from seawater,   the latter needs to be saturated in this mineral. Now a report from NOAA scientists found large quantities   of water undersaturated in aragonite are already upwelling close to   the Pacific continental shelf from Vancouver to northern California   [v]. Although the study only dealt   with the area, the authors suggest that other shelf areas may be experiencing   similar effects.

For   corals like those in Australia’s Great Barrier Reef, the outlook is grim. They   are threatened with destruction on two fronts, both caused by CO2   emissions. Not only do increased ocean temperatures bleach coral by forcing   them to expel the algae which supplies them with energy (see photo at left) [viii], but   increased ocean CO2   reduces the availability of aragonite from which reefs are made.

It is time to   wake up. Our planet is dying. I urge you to find the time to view a 20 minute   documentary on the problem of ocean acidification produced by the international   Natural Resource Defence Council. Simply go to www.acidtestmovie.com.



Fig 5. Coral killed by above average ocean temperatures.

References   and Notes

   [i]  pH is a measure of the acidity or alkalinity     of a solution. It uses a negative logarithmic scale where a decrease of 1.0     units represents a 10-fold increase in acidity. In     their natural state prior to industrialization, the oceans were slightly alkaline     with a pH of 8.2 (see reference iii). Pure water has a pH of 7.0.
   [ii]  Feely R., Doney S., Cooley S. (2009).     Present Conditions and Future Changes in a High-CO2 World.     Oceanography 22, 36-47
   [iii]  Australian Antarctic Division, Ocean Acidification and     the Southern Ocean, available at www.aad.gov.au/default.asp?casid=33583
   [iv] Feely, Doney and Cooley, op. cit, using     Mauna Loa data from the US National Oceanic and Atmospheric Administration     and Aloha data from the University of Hawaii.
   [v] Feely     RA, Sabine CL, Hernandez-Ayon JM, Ianson     D, Hales B (June 2008). Evidence for upwelling of corrosive     "acidified" water onto the continental shelf. Science 320 (5882): 1490–2,     available at http://www.sciencemag.org/content/320/5882/1490
   [vi] Inter Press Service, Acid Oceans Altering Marine Life,     available at http://ipsnews.net/news.asp?idnews=46055
   [vii] Australian Broadcasting Corporation, Ocean Acidification     – The Big Global Warming Story, downloadable at http://www.abc.net.au/catalyst/stories/s2029333.htm
   [viii]  Great Barrier Reef Marine Park Authority, What is Coral     Bleaching?, available at http://www.gbrmpa.gov.au/corp_site/key_issues/climate_change/climate_change_and_the_great_barrier_reef/what_is_coral_bleaching

2011-03-07 14:04:07Ocean Acidification Isn't Serious: Second Draft Ready For Review
alan_marshall

alan.from.tas@gmail...
58.169.133.244

 

I have produced a revised version of the intermediate rebuttal which incorporates some, but not all, of the above changes suggested by others in this forum.

Summary of Changes:

  • All images are now clearly labelled
  • There are now two pairs of images showing damage to microscopic marine life. The first pair shows the result of simulated future ocean chemistry, while the second pair shows the result of current conditions in the Southern Ocean.
  • The first image in the second pair has been magnified by a further 20% to match the second image. The 10 fold increase in the number of holes in the second image is pointed out. These images may be among the first incontestable evidences that damage from ocean acidification is already occurring.
  • So called "emotive language" has been toned down in some places. That which I have left in place I believe to be appropriate to the nature and scale of the threat.
  • Discussion of the effect on corals has been separated form discussion of effects on microscopic marine life to avoid confusion
  • A third chemical equation has been added to the explanation of ocean chemistry

I think the rebuttal is better for the changes. I encourage those who reviewed my first version to have another look and decide whether it now deserves a green "thumbs up". If approved, it will replace the existing intermediate rebuttal. (The paleo-climate evidence from the latter will be moved to the advanced version).


2011-03-07 19:59:30
nealjking

nealjking@gmail...
91.33.112.134

"However, if CO2 is allowed to rise along a business as usual trajectory,"

=>

"However, if CO2 is allowed to rise along a "business-as-usual" trajectory,"

================================================================================

"The photo below left shows healthy phytoplankton. The photo below right shows the damage to the same creature under conditions expected by the end of the century (see Fig. 1)."

- The photo below is Fig. 3, not Fig. 1.

- Again, it is not clear to the untrained eye what the difference is between the photos left and right. Can you please point it out?

================================================================================

Fig.4: The left-hand photo doesn't show up.

================================================================================

2011-03-09 15:03:07Thumbed
John Cook

john@skepticalscience...
124.186.229.6

Great overview, Alan. Also fixed the broken image and the link to the acid test movie.

Actually, just had a thought - what do you think of embedding the acid test Youtube in your post? I can do that for you if you like the idea.

2011-03-09 21:32:25
Rob Painting
Rob
paintingskeri@vodafone.co...
118.93.231.184

Although I agree with Neal, this has languished for too long. Get er' done!