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Post by marchesarosa on Sept 22, 2010 10:48:27 GMT 1
scienceandpublicpolicy.org/images/stories/papers/originals/acid_seas.pdfAcid Seas Back to Basic by Dennis Ambler This is another case of teasing a trend out of noisy data in which the supposed trend is smaller than measurement precision and accuracy; and normal variability is many times greater. The measurement of global mean oceanic pH is no more reliable than that of measurement of global mean temperature. This is another area of science that has been corrupted, with scientists producing scare-mongering claims about “acid oceans”. This is what the IPCC says in AR4: “The consequences of changes in pH on marine organisms are poorly known (see Section 7.3.4 and Box 7.3). For comparison, pH was higher by 0.1 unit during glaciations, and there is no evidence of pH values more than 0.6 units below the pre-industrial pH during the past 300 million years (Caldeira and Wickett, 2003)12. A decrease in ocean pH of 0.1 units corresponds to a 30% increase in the concentration of H+ in seawater, assuming that alkalinity and temperature remain constant.” Hence we get the claim that “the ocean” has become 30% more acidic since the start of the industrial revolution. There can be no single pH value for the world’s oceans, any more than there can be a single surface-air temperature for the globe. The range of pH can vary extensively from as low as 7.8 to as high as 8.4 in a single 24 hr period (Yates and Halley, 2006). In some lagoons, pH has been measured to vary as much as 1 pH unit in a day (e.g., 7.6 to 8.6). Seasonal and even multi-decadal cycles of pH variation in reef water have also been measured (Pelejero et al., 2005). ..alkalinity already present in seawater can prevent severe pH excursions for periods of thousands of years even when reverse weathering is neglected. If reverse weathering is taken into account, then the buffering capacity of the CO2 system extends for much longer periods. The actual pH of seawater is fixed by any two relevant quantities and, as the alkalinity is controlled by the input of HC03- from weathering and the biogenic output of CaC03 and the Pco, below the thin wind-mixed layer is controlled by oxidation, the pH is determined primarily by biological processes. Of course, geochemical events, such as weathering …. and chemical equilibria also play a role. Atmospheric CO2 rose as high as 2500 ppm between 60 and 40 Ma and Caldeira and Wicket say that there is no evidence for a greater than 0.6 decrease in pH in the last 300 Ma, so even with CO2 levels six and a half times greater than today, the oceans were still not acid. The current acid ocean scare has been fed by the Caldeira and Wicket paper from 2003. The use of the word acidic to describe levels that are still alkaline is designed to ramp up the scare element.
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Post by marchesarosa on Sept 22, 2010 10:51:41 GMT 1
The Electric Oceanic Acid Test Extracts from article posted on June 19, 2010 by Willis Eschenbach Guest Post by Willis Eschenbach wattsupwiththat.com/2010/06/19/the-electric-oceanic-acid-test/.....The first thing that I learned is that when you go from the tropics (Hawaii) to the North Pacific (Alaska), the water becomes less and less alkaline. Who knew? So even without any CO2, if you want to experience “acidification” of the ocean water, just go from Hawaii to Alaska … you didn’t notice the change from the “acidification”? You didn’t have your toenails dissolved by the increased “acidity”? Well, the sea creatures didn’t notice either. They flourish in both the more alkaline Hawaiian waters and the less alkaline Alaskan waters.... The second thing I learned from the study is that the pH of the ocean is very different in different locations. As one goes from Hawaii to Alaska the pH slowly decreases along the transect, dropping from 8.05 all the way down to 7.65. This is a change in pH of almost half a unit. And everywhere along the transect, the water at depth is much less alkaline, with a minimum value of about 7.25. The third thing I learned from the study is how little humans have changed the pH of the ocean. Figure 3 shows their graph of the anthropogenic pH changes along the transect. The full-sized graphic is here: The final thing I learned from this study is that creatures in the ocean live happily in a wide range of alkalinities, from a high of over 8.0 down to almost neutral. As a result, the idea that a slight change in alkalinity will somehow knock the ocean dead doesn’t make any sense. By geological standards, the CO2 concentration in the atmosphere is currently quite low. It has been several times higher in the past, with the inevitable changes in the oceanic pH … and despite that, the life in the ocean continued to flourish. My conclusion? To mis-quote Mark Twain, “The reports of the ocean’s death have been greatly exaggerated.” |
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Post by abacus9900 on Sept 22, 2010 11:13:48 GMT 1
 Change in sea surface pH caused by anthropogenic CO2 between the 1700s and the 1990s."Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.179 to 8.104, a change of −0.075 on the logarithmic pH scale which corresponds to an increase of 18.9% in H+ (acid) concentration. By the first decade of the 21st century however, the net change in ocean pH levels relative to pre-industrial levels was about -0.11, representing an increase of some 30% in "acidity" (ion concentration) in the world's oceans." en.wikipedia.org/wiki/Ocean_acidification |
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Post by marchesarosa on Sept 22, 2010 12:09:46 GMT 1
Who was measuring the earth's oceans' pH back in 1751, abacus? (and supposedly to three decimal places?)
Who was measuring them AT ALL until very recently?
Previous measures are just "estimates".
Your map is plain invention.
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Post by enquirer on Sept 23, 2010 13:48:54 GMT 1
Who was measuring the earth's oceans' pH back in 1751, abacus? (and supposedly to three decimal places?) Who was measuring them AT ALL until very recently? Previous measures are just "estimates". Your map is plain invention. From www.whoi.edu/OCB-OA/FAQs/#3" How do we know what ocean pH was in the past even though the pH scale was not introduced until 1909? When ice sheets build up into glaciers, air bubbles become trapped in the freezing ice. Scientists have analyzed the CO2 concentration of air in these bubbles and have developed a record of the atmospheric CO2 concentration in the recent past. Because large parts of the surface ocean CO2 concentration remains roughly in equilibrium with the atmospheric CO2 concentration, the ocean CO2 content can be calculated from these air bubbles, and ocean pH can also be calculated. In fact, the ice core record shows that the atmospheric CO2 concentration has never been higher than about 280 ppm during the last 800,000 years, creating conditions leading to an average preindustrial surface ocean pH of ca. 8.2. — Jelle Bijma, Biogeochemist, Alfred Wegener Institute for Polar and Marine Research, Germany" Sounds quite straight forward to me. |
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Post by marchesarosa on Sept 23, 2010 14:08:15 GMT 1
You missed this FAQ, enquirer
Would dissolving all the CO2 released by burning all the world’s fossil fuel reserves ever make the seas acidic?
No. The fundamental chemistry of the ocean carbon system, including the presence of calcium carbonate minerals on the ocean floor that can slowly dissolve and help neutralize some of the CO2, prevents the oceans from becoming acidic on a global scale. — Christopher L. Sabine, Supervisory Oceanographer, NOAA Pacific Marine Environmental Laboratory, USA
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Post by enquirer on Sept 23, 2010 14:11:10 GMT 1
No I didn't
I was referring to your post that claimed that it was impossible to know the pH of oceans in the past.
The site I linked to explained how they do that - that's all.
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Post by marchesarosa on Sept 23, 2010 14:38:09 GMT 1
As I stated before previous purported "measures" were just estimates. The CO2 level has gone up and down in Earth's recent geological past just as temperatures have as you would know if you had ever looked at the ice core data you refer to.
There is no "Goldilocks" level of either CO2, or temperature or pH that is "just right". The map is invention and "acifification" story is just more scare-mongering from the usual suspects.
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Post by enquirer on Sept 23, 2010 14:47:24 GMT 1
Yes dear, whatever you say
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Post by StuartG on Sept 23, 2010 15:17:35 GMT 1
'Because large parts of the surface ocean CO2 concentration remains roughly in equilibrium with the atmospheric CO2 concentration, the ocean CO2 content can be calculated from these air bubbles, and ocean pH can also be calculated. In fact, the ice core record shows that the atmospheric CO2 concentration has never been higher than about 280 ppm during the last 800,000 years, creating conditions leading to an average preindustrial surface ocean pH of ca. 8.2'
where do these ice-cores come from?
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Post by marchesarosa on May 25, 2011 12:32:54 GMT 1
Can oceans be supposedly “acidifying” and supposedly warming at the same time?
I thought colder oceans absorbed more CO2 and warmer ones outgassed CO2 thereby becoming less “acidic”
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Post by StuartG on Jun 6, 2011 4:20:25 GMT 1
Psst! "Ocean acidification could make fish deaf" planetearth.nerc.ac.uk/news/story.aspx?id=986"Young fish use the chirps and clicks that come from noisy coral reefs to figure out where to set up home. If they can't hear those sounds, they could be doomed. " Underlying, subliminal message... If you don't reduce the CO2 levels, then yer gonna die [doomed]. full .pdf... rsbl.royalsocietypublishing.org/content/early/2011/05/25/rsbl.2011.0293.full.pdfThere is no subtlety about the message in the .pdf "1. INTRODUCTION Since the Industrial Revolution, approximately 142 billion tonnes of anthropogenic CO2 has been absorbed by the oceans, resulting in ocean acidification at a rate far faster than any time in the last 650 000 years [1], and causing the average pH of the ocean to drop by 0.1 units [2]. If global emissions continue on the current trajectory, atmospheric CO2, currently at 390 ppm, is predicted to reach 730–1020 ppm by 2100 [2,3], causing a further drop in ocean pH of 0.3–0.4 units [1,2]. Acidified conditions compromise the ability of marine calcifiers to build skeletons and shells [4], but the combined influences on noncalcifiers including fishes are far less understood [5]. " That's not science, but then I'm no scientist, what do others think? Ref (4) says... "Today's surface ocean is saturated with respect to calcium carbonate, but increasing atmospheric carbon dioxide concentrations are reducing ocean pH and carbonate ion concentrations, and thus the level of calcium carbonate saturation. Experimental evidence suggests that if these trends continue, key marine organisms—such as corals and some plankton—will have difficulty maintaining their external calcium carbonate skeletons. Here we use 13 models of the ocean–carbon cycle to assess calcium carbonate saturation under the IS92a ‘business-as-usual’ scenario for future emissions of anthropogenic carbon dioxide. In our projections, Southern Ocean surface waters will begin to become undersaturated with respect to aragonite, a metastable form of calcium carbonate, by the year 2050. By 2100, this undersaturation could extend throughout the entire Southern Ocean and into the subarctic Pacific Ocean. When live pteropods were exposed to our predicted level of undersaturation during a two-day shipboard experiment, their aragonite shells showed notable dissolution. Our findings indicate that conditions detrimental to high-latitude ecosystems could develop within decades, not centuries as suggested previously. To read this story in full you will need to login or make a payment " www.nature.com/nature/journal/v437/n7059/full/nature04095.htmlRef (1) says... "Ocean acidification due to increasing atmospheric carbon dioxide" but note it says it's a 'policy document' [perhaps somebody can put me right on that, before any other conclusions are drawn] eprints.ifm-geomar.de/7878/1/965_Raven_2005_OceanAcidificationDueToIncreasing_Monogr_pubid13120.pdfand text... "Carbon dioxide (CO2) emitted to the atmosphere by human activities is being absorbed by the oceans, making them more acidic (lowering the pH the measure of acidity). " and that's the contentious bit.. "by human activities" although this is true, if we make CO2 by some process and let it to atmosphere, there's a good chance that it [or a good part of it] will be dissolved in the sea, is that percentage greater than the 'natural' production ['juvenile'] royalsociety.org/Ocean-acidification-due-to-increasing-atmospheric-carbon-dioxide/anyway I'll close now, You adherents think of these ideas from the scientists next time the ring pull is tugged on a can of 'fizzy-pop' or beer. Psst! Cheers StuartG |
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Post by speakertoanimals on Jun 7, 2011 13:58:40 GMT 1
Estimates? Well, as far as I know, measuring CO2 from ice cores is an actual measurement. From that, we then have to infer what happened to sea CO2 levels at the same time, but that sort of inference ISN'T an estimate (in the could be totally incorrect measurement sense that M seems to use it). Recent geological past is a red-herring, since we all KNOW that over geological time, CO2 has varied greatly (as have the distributions of the continents, ocean circulation patterns, mega-volcanism etc). But is M REALLY suggesting that the same processes that have effected levels over such geological times are responsible now? Even when we look at the past 420,000 years, the rise in the last 150 years is still significant, even compared to previous inter-glacials. And let's not forget we can measure OTHER greenhouse gases in these cores (e.g., methane), not just CO2. So, look at the data is my advice. news.bbc.co.uk/1/hi/sci/tech/5314592.stm |
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Post by marchesarosa on Jun 7, 2011 14:07:12 GMT 1
Atmospheric CO2 in icecores does not determine the level of CO2 in the ocean. It is the other way round. Tail and dog, remember?
Warmer ocean = outgassing, cooler ocean = absorption. NOTHING to do with atmospheric levels of CO2. EVERYTHING to do with ocean temperature i.e the sun, the clouds and the planetary situation.
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Post by speakertoanimals on Jun 7, 2011 15:30:42 GMT 1
Who was the one claiming that we didn't understand enough of the carbon cycle? NOW you claim that we can discount gas exchange between atmosphere and the upper ocean, and that increasing levels in the atmosphere WON'T increase levels in the ocean, or that there is ANY equilibrium between the two!
Sorry, but this is PANTS. You can't claim both that things are complicated (i.e., CO2 goes from ocean to atmosphere, and vice versa, I won't like to say off the top of my head WHICH drives the other under any given condition, but I'm willing to admit they probably both effect the other), and that they're so simple that levels of CO2 in sea-water are UNAFFECTED by atmospheric levels.
The level in the atmosphere is going to be related to the levels in the upper ocean, by simple gas exchange, AND the exact relationship depends on temperature as well. It in itself doesn't tell you which drives the other, but we hadn't got to that yet! We were just looking at the increasing CO2 in ice-cores and correlation with historical record of fossil fuel use.
Interesting that some sites claim no correlation between CO2 levels and temp, whereas the CO2 and deuterium levels in ice cores DO show a correlation, and there is a correlation between deuterium levels and temperature (our old friend isotopic chemistry again!).
Sorry, but is ODD that when one of us points out something, you fall back on the 'things are complicated' argument, except when you want to use the things are simple and go this way argument. You can't have it both ways!
I'll admit its' complicated, that is why I'm taking teeny steps, like the isotopic analysis of volcanic versus fossil CO2, now the teeny steps with ice-core data for CO2, methane, and deuterium.
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