A lesser-known consequence of having a lot of carbon dioxide (CO2) in the air is the acidification of water. Oceans naturally absorb the greenhouse gas; in fact, they take in roughly one third of the carbon dioxide released into the atmosphere by human activities. When CO2 dissolves in water, it forms carbonic acid, the same substance found in carbonated beverages. New research now suggests that seawater might be growing acidic more quickly than climate change models have predicted.
Marine ecologist J. Timothy Wootton of the University of Chicago and his colleagues spent eight years compiling measurements of acidity, salinity, temperature and other data from Tatoosh Island off the northwestern tip of Washington State. They found that the average acidity rose more than 10 times faster than predicted by climate simulations.
Highly acidic water can wreak havoc on marine life. For instance, it can dissolve the calcium carbonate in seashells and coral reefs [see “The Dangers of Ocean Acidification,” by Scott C. Doney; Scientific American, March 2006]. In their study, published in the December 2 Proceedings of the National Academy of Sciences USA, Wootton and his team discovered that the balance of ecosystems shifted: populations of large-shelled animals such as mussels and stalked barnacles dropped, whereas smaller-shelled species and noncalcareous algae (species that lack calcium-based skeletons) became more abundant. “I see it as a harbinger of the trends we might expect to occur in the future,” says oceanographer Scott C. Doney of the Woods Hole Oceanographic Institution, who did not participate in this study.
Wootton notes that the changes his team saw were linked with growing levels of atmospheric CO2, but he readily acknowledges that the global-warming gas might not be the main culprit in this surge in acidity. Instead the acidification the researchers observed could have resulted from a nearby upwelling of deep ocean water loaded with carbon, so the results might not apply to the oceans as a whole. Still, the acidity readings along the Pacific coast of the U.S. and in the Netherlands do seem to be rising, Wootton says, “and that seems consistent with our pattern.” Marine life, it seems, may not have the luxury of time to act as a buffer against the changing waters.
Note: This article was originally printed with the title, "Acid Bath".
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17 Comments
Add CommentThis is garbage. CO2 accounts for 0.038% of earth's atmosphere. People, if a Benjamin represented the chemical composition of the earth's atmosphere, CO2 would be worth 3.8 cents. Water vapor, at 1%, is much more a part of climate change. This biggest culprit? That big, yellow thing in the sky that is so hot it heats this entire ball of dirt to an average 70 deg F.
Reply | Report Abuse | Link to thisLiars.
Yeah, what Magnus said. And cholesterol probably makes up a similarly small amount of your body mass so don't believe all that cholesterol garbage either. (disclaimer: I am not a medical doctor. Maybe Magnus should put a disclaimer up about whether he knows anything about atmospheric chemistry)
Reply | Report Abuse | Link to thisCiting sources for those who are more passion than brains.
Reply | Report Abuse | Link to thishttp://en.wikipedia.org/wiki/Earth%27s_atmosphere
My point was that just knowing the relative concentration of anything tells me nothing about its importance to the processes involved. I do not pretend to understand the physics or chemistry involved. If you do, I would like you to enlighten us beyond simple statements about relative concentrations.
Reply | Report Abuse | Link to thisWell, the article does note "that the global-warming gas might not be the main culprit in this surge in acidity. Instead the acidification the researchers observed could have resulted from a nearby upwelling of deep ocean water loaded with carbon . . ." It's just a short side bar that's more of a "how about this? Probably doesn't mean much but it's something to consider."
Reply | Report Abuse | Link to thisCheck this out, then.
Reply | Report Abuse | Link to thisThe BBC ran an article this week titled Acid oceans need urgent action based on the premise:
The worlds marine ecosystems risk being severely damaged by ocean acidification unless there are dramatic cuts in CO2 emissions, warn scientists.
This sounds very alarming, so being diligent researchers we should of course check the facts. The ocean currently has a pH of 8.1, which is alkaline not acid. In order to become acid, it would have to drop below 7.0. According to Wikipedia Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.179 to 8.104. At that rate, it will take another 3,500 years for the ocean to become even slightly acid. One also has to wonder how they measured the pH of the ocean to 4 decimal places in 1751, since the idea of pH wasnt introduced until 1909.
The BBC article then asserts:
The researchers warn that ocean acidification, which they refer to as the other CO2 problem , could make most regions of the ocean inhospitable to coral reefs by 2050, if atmospheric CO2 levels continue to increase.
This does indeed sound alarming, until you consider that corals became common in the oceans during the Ordovician Era - nearly 500 million years ago - when atmospheric CO2 levels were about 10X greater than they are today. (One might also note in the graph below that there was an ice age during the late Ordovician and early Silurian with CO2 levels 10X higher than current levels, and the correlation between CO2 and temperature is essentially nil throughout the Phanerozoic.)
http://wattsupwiththat.com/2009/01/31/ocean-acidification-and-corals/
I think this article has less to do with global warming than it does with how anthropogenic CO2 emissions are potentially increasing the acidity of the ocean. I'm also pretty sure that, if the sun were solely responsible for global warming, CO2 levels in the ocean would decrease rather than increase.
Reply | Report Abuse | Link to thisKudos to Magnus. I am glad you are at least citing information to support your contention that any scientist who claims mankind is in any way responsible for the recnet (last 100 years or so) warming trend - are just liars.
Reply | Report Abuse | Link to thisJust so you know, I think I will trust the people who have made it their livlihood and passion to understand and explain climate (the same people who likely generated much of the information you can google/wiki), over some of us half baked experts, who think a couple quick internet facts can disprove evidence that is so overwhelming.
Just saying... but.... good internet search skills. ;-)
When acid rain was eating monuments in Greece and Gettysburg and elsewhere a few years ago, I don't recall that anyone was blaming the big yellow thing in the sky. I seem to recall from chemistry class that carbonic acid, although not as strong as sulfuric or nitric, can do a job on limestone, given enough time.
Reply | Report Abuse | Link to thisNow, correct me if I am wrong, but doesn't the solubility of carbon dioxide in water decrease as the temperature rises? I'm not sure how the solubility rules hold up to salt water, but if there has been a net increase in temperature due to global warming, would that not warm the oceans slightly and cause them to release carbon dioxide into the atmosphere as the solubility decreases?
Reply | Report Abuse | Link to this...or is it that since the ocean is not a saturated solution of carbon dioxide that the temperature has little to no effect on the amount of carbon dioxide being dissolved. It may simply be a matter of Le Chatelier's Principle if this is the case.
Reply | Report Abuse | Link to thisI do not know how many times I have seen an article such as this that states that new research has shown that x is happening far more quickly than predicted by the models. X, of course, is always a bad thing and the purpose the article seems to be to raise the level of concern on climate change.
Reply | Report Abuse | Link to thisHowever what I don't understand is why people don't draw the obvious conclusion that as scientists we should draw - the models are just plain wrong!
magnus205, good points but you are discounting a few important details.
Reply | Report Abuse | Link to thisFirstly, location matters. The ocean does not absorb carbon from the atmosphere equally at all depths. The concentration is highest at the interface between the surface of the ocean the atmosphere. Ergo, the surface waters will acidify more quickly than the deeper water. The dissolved carbon will eventually diffuse to deeper water but not instantaneously. This means you could have a low pH building up at the surface and a normal pH at other depths.
Another thing you are forgetting is that it is the 'rate of change' that is important thing here, not the absolute measurement. Organisms will adapt to changing conditions if it occurs slowly enough (i.e. over geological time). Indeed, its one of the foundations of evolutionary theory that species will adapt to suit their environment. The problem here is that the changes in temperature (or ocean pH) are proceeding at a rate which is unprecedented in history, that is, it is occurring over decades rather than over thousands of years. Can species evolve fast enough to keep up with that rate of environmental change?
Sure, there might have been corals that were adapted to living in acidic oceans in the Ordovician period, but that says nothing about the coral species that are living today. Is that a chance that you want to take? I for one like living next to the Great Barrier Reef.
As for the argument that CO2 is such a tiny proportion of the atmosphere that increasing its concentration in the atmosphere couldnt possibly have an effect, well that's just what I like to call the "fallacy of scale". For example, I am allergic to aspirin. If I ingest a few molecules of salicylic acid I go into anaphylactic shock and earn a trip to ER in an ambulance. Compared to my total body mass, those few molecules are a tiny proportion. Small things can have big effects.
In the same vein, the issue with increasing the amount of CO2 in the atmosphere is that CO2 blocks a very specific range of infrared radiation (i.e. heat being re-radiated from the Earth that would otherwise end up in space). Up until industrial times, there was a balance between carbon sinks and emitters. Once the large-scale combustion of fossil fuels became wide-spread, this balance was tilted in favour of emitters. Even though in absolute terms this increase is only tiny, it means that the heat budget for Earth is slowly increasing, just like interest in a savings account.
Hi!: as water heats, it can hold in solution a lesser amount of gases, CO2 among them, but the process is probably unimportant in the temperature range of seas we face; there must be somebody able to calculate the figures. The amount of CO2, and thus, acidification the water can accept is not unlimited, when sea temperature rises, water starts emitting soluted gases back to atmosphere, it may be some kind of self-regulatory process. Anybody able to enter a computer and make predictions? Regards
Reply | Report Abuse | Link to thisIn the article on acidification of seawater by dissolution of carbon dioxide
Reply | Report Abuse | Link to this(C. Q. CHOI Feb. 2009), it states that ".. it can dissolve calcium carbonate
in sea shells and coral reefs".
Carbonic acid (if it actually exists) is one of the weakest acids known, and
the hydrogen ion concentration it produces is irrelevant in the CaCO3 <- ->
Ca++ + CO3-- equilibrium.
My physical chemistry tells me, via mass action laws and the equilibrium
constant, that any additional carbonate ions will actually stabilise any
solid calcium carbonate present in the system !
Can Choi resolve this apparent paradox for me ?
A concentration of 1 part per thousand of carbon monoxide is fatal for humans. We fall over. We die. That's a small concentration with a huge effect. And how much of our body weight has to be arsenic before it is fatal? The kind of argument Magnus makes is fallacious and misleading. Carbon dioxide is an effective greenhouse gas because it remains in the atmosphere, continuing to capture infrared light for hundreds of years. The coal burning stoves of Victorian England which turned the fogs of London thick and yellow in the 19th C. also sent C02 into the atmosphere which is even today contributing to Global climate change. The kettles on those stoves also sent water vapour, another greenhouse gas, into the atmosphere, but the affect of that water vapour dissipated long, long ago when the water vapour condensed as dew or fell a precipitation. A little guy working for a hundred years will do more work than a hundred large men working for a week. In that sense the little guy is more important than the hundred large men.
Reply | Report Abuse | Link to thisA concentration of 1 part per thousand of carbon monoxide is fatal for humans. We fall over. We die. That's a small concentration with a huge effect. And how much of our body weight has to be arsenic before it is fatal? The kind of argument Magnus makes is fallacious and misleading. Carbon dioxide is an effective greenhouse gas because it remains in the atmosphere, continuing to capture infrared light for hundreds of years. The coal burning stoves of Victorian England which turned the fogs of London thick and yellow in the 19th C. also sent C02 into the atmosphere which is even today contributing to Global climate change. The kettles on those stoves also sent water vapour, another greenhouse gas, into the atmosphere, but the affect of that water vapour dissipated long, long ago when the water vapour condensed as dew or fell a precipitation. A little guy working for a hundred years will do more work than a hundred large men working for a week. In that sense the little guy is more important than the hundred large men.
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