CO2 emissions could affect ocean life in many unexpected ways. (Melanie Stetson Freeman/Staff/File)
Warming seas create a massive chemistry experiment
Rising acidity in oceans and accelerating wind patterns may lead to unexpected changes.
By Robert C. Cowen | Columnist for The Christian Science Monitor/ October 16, 2008 edition
Science columnist Robert C. Cowen discusses how climate change affects seawater chemistry and sound transmission beneath the waves.
Science columnist Robert C. Cowen
Global warming of the sea is affecting the atmosphere and ocean in subtle ways, adding a new dimension to the concept of global change.
As carbon dioxide accumulates in the air, more of it dissolves into the sea. This gradually increases sea-water acidity. Biologists have been concerned about what this could do to corals and other animals that have adapted to live in fairly constant marine conditions. Now scientists also have to take account of changes to seawater chemistry.
Keith Hester and colleagues, who are exploring ocean acidity at the Monterey Bay Aquarium Research Institute (MBARI) in Moss Landing, Calif., explained this new perspective earlier this month in Geophysical Research Letters.
“The waters of the upper ocean are now undergoing an extraordinary transition in their fundamental chemical state at a rate not seen on Earth for millions of years, and the effects are being felt not only in biological impacts but also on basic geophysical properties, including acoustics,” they note.
Seawater chemistry affects how water absorbs sound. It’s a poorly understood process in which a variety of chemical interactions determines how molecules absorb sound at specific frequencies. Increasing seawater acidity favors transmission of low- to mid-frequency sound. Marine mammals rely on sound in this range to communicate and to find food and mates.
According to the MBARI announcement, its research team estimates “that sound already may travel 10 percent farther in the oceans than it did a few hundred years ago.” The team projects that by midcentury, sound may travel as much as 70 percent farther than it does today.
It’s unknown how this might affect the behavior of marine mammals. But this research, as the announcement points out, “shows once again how human activities [such as CO2 pollution] are affecting Earth in far-reaching and unexpected ways.”
You can say that about the reach of sea surface warming into the tropical stratosphere, an atmospheric layer that begins seven to 10 miles above ground and extends to approximately 30 miles. Circulation of air and moisture that rises in the tropics into the stratosphere spreads out and then sinks back down in higher latitudes. This wind pattern, a basic aspect of our climate system, is called the Brewer-Dobson circulation. Global warming is apparently changing this pattern in ways not fully understood. In a research review in Science two weeks ago, Rudolf Deckert and Martin Dameris at Germany’s Institute for Atmospheric Physics note that this basic circulation seems to be accelerating.
This development would not only change key physical aspects of atmospheric circulation, it could also redistribute and otherwise change the chemical composition of the air from the stratosphere down to the ground.
“[The] Brewer-Dobson circulation is likely to intensify in a future climate with higher SSTs [sea surface temperatures], with implications not only for the chemical composition and climate of the stratosphere but also at Earth’s surface,” the review authors explain.
It seems that CO2 pollution is not only an inadvertent climate experiment, it’s also the biggest chemistry experiment we’ve ever run.
( More stories )
Comments
2. Rob | 10.17.08
Yes thats true Co2 is found in nature.
But just like everything else an excessive amount acts like poison.
If you want to negate this affect you need to reduce consumption and burning carbonm base fuels.
Alternatives to reduce this are out there available to the public. The Governments need to create incentives that make the public go green. Untill this is done the green term will be just a term nothing more.
3. Timothy | 10.17.08
Funny, not once does the article call CO2 a pollutant but states that the higher concentrations of it in the atmosphere are creating a more acidic ocean. Natural substances in the wrong amounts can cause problems. Question is: what is truly responsible for the increase in CO2?
4. michelle | 10.17.08
The article discusses a very important issue which is the balance of chemistry that has been maintained for 1000’s of years in our oceans. Now the balance is such that Co2 is increasing and unbalancing and causing a chemical reaction that is different than previously seen. I believe that the Co2 in an unbalanced state is considered a pollutant in that it is unbalancing what has been in place. I know if the right balance is not maintained we could sufficate in our environment. I enjoyed the article and gives pause to consider what the animals of the sea could be experiencing.
5. Pete | 10.17.08
George- CO2 absolutely can be considered a pollutant. A pollutant is any contaminant introduced that adversely alters the physical, chemical, or biological properties of the environment. …
(see: http://www.soil.ncsu.edu/publications/BMPs/glossary.html) Whether it occurs in nature is irrelevant. For example, mercury occurs naturally in the environment but when introduced at high levels into the atmosphere or surface waters is toxic to organisms including humans. As is CO2. Hopefully you have a CO2 detector in your house to detect excess levels before it can harm you or your family.
6. Marwan Nusair | 10.17.08
The oceans have a huge thermal mass both because of it’s enormous volume and because water has a very high specific heat, and it takes about 800 years or more (depending on currents and circulation) before the ocean changes it’s temperature as a result of either warming or cooling at the surface. If the oceans are warming now, that can only be due to the Medieval Warming Optimum which occured broadly from the 10th to the 13th centuries. Ocean levels, for example, started to rise in the 18th century and continue to rise at about a foot (give or take a couple of inches) per century since then. I am not clear how ocean temperature and it’s effect on the atmosphere could have been caused by humans, whether CO2 is important or not. Human-caused CO2 is a very recent phenomenon and it’s impact on the oceans simply cannot be felt yet - perhaps in 2700 to 2800 AD our descendants will measure it.
The acidification of the oceans, at least near the surface, is a different and unrelated phenomenon, and is interesting to consider. Ocean surface acidity has increased (pH decreased by about 0.l in the last several decades, I regret that I cannot lay my hands on the right reference, so this is from memory). Whether this will result in a reaction and eventual equilibrium remains to be seen - most natural phenomena end up in equilibrium and runaway reactions are rare. It’s clear that with natural CO2 exchange at just under 800 gigatons per year, and human activity at about 26 (possibly increasing to over 30 by mid-century), the proportions do not immediately suggest that we have a large effect.
Interesting work.
7. isahbiazhar | 10.17.08
I stay by the South China Sea and in a span of 40 years I see the dwindling catch from the sea.Already the price of fish had gone up from US1 to almost US3 per kilogram the cheapest fish.People are not at all concerned about pollution but continue destroying the little bit of marine life.Greed for the present is contributing to the destruction of the future.Man/Woman never learn.
8. Pat Arrington | 10.17.08
Looking in a few dictionaries I could detect no usage problem with the word “pollution.” I can, however, understand why George didn’t sign his name.
Thanks for this article and for the inspiring photo.
I’d like to buy a copy of your book, Robert Cowen, to give to a friend. I vividly recall reading it in the 1970’s. Some of it may be out of date, but it was so lucidly written I believe it might serve as a solid background on climate change. It wasn’t, “Frontiers of the Sea” ?
All the best wishes
9. Sam | 10.17.08
Obviously CO2 is found naturally and is absolutely essential for life on Earth, but this article is probably intended to highlight the effects of CO2 release by anthropogenic sources.
Historically, CO2 levels have been much higher than they are now but at those times everything else in our environment was also very different. The article is suggesting that the anthropogenic release of CO2 can help drive our environment to change in a way that we don’t quite fully understand, perhaps to a resemble an earlier state with much higher temperatures
10. Angie Mom | 10.17.08
So, George, would it be ‘more better’ to say the polluting ratio of man made Co2, as opposed to natural occurring Co2, now found in our atmosphere..
11. Andrew Zwick | 10.18.08
I have to admit I find this very interesting. I live by NCAR (National Center for Atmospheric Research), and if you go there you will see how seriously they are worried about climate change. it is worth visiting if you are ever in Colorado.
My biggest question, having one biology class on climate, is what does this due to the desert belt stretching from 30 deg. n. and s.?
12. Tony | 10.18.08
No offense, George, but your comment is a bit off in accuracy. First, water vapor is just that - H2O droplets - it is NOT a gas (for atmospheric H2O to be a gas the atmosphere would have to be over 212 degrees Farenheit). Secondly, you are misusing or misunderstanding the scientific use of the term “pollutant” with common usage. When we speak of a “pollutant” in the strict sense, as in this article, we mean any substance that in excess adversely affects the environment. For eample: asbestos is commonly referred to as a pollutant and I expect (perhaps wrngly) that you would agree. But asbestos, by itself, is very common in (for example) serpentine rocks which are found all over the world. It is human’s excessive and careless production and use of it that has given rise to “asbestos pollution.” That is also true with respect to excess CO2. Finally, we have never had so high and (what is far more important) RAPID an increase in any atmospheric gas in the 2+ billion years that can be studied. Frankly, it sounds as though you are one of the few holdouts still doubting “Global Warming”. Your choice, of course, but please get your facts straight before you write.
13. Laurie | 10.18.08
Earth is a benevolent system created by God. The changes we see are more likely the earth balancing out human’s mistakes, than evidence that humans can destroy God’s creation. We should strive to bless the whole earth with our actions, but a merciful creator is still with us all and above all. Fear not!
14. Rosemarie Cardoso | 10.18.08
Would it be possible to add Yuniti.com on the “ShareThis” so I can share this and other good articles with people there? Thanks.
15. sue | 10.18.08
From Wikipedia, the free encyclopedia
” Pollutants, the elements of pollution, can be foreign substances or energies, or naturally occurring; when naturally occurring, they are considered contaminants when they exceed natural levels.”
16. Eric | 10.18.08
A very interesting, but disturbing, article. I deeply appreciate the Monitor’s committment to report regularly on such vital issues.
17. AWBilinski | 10.18.08
Hi George,
The article actually refers to “co2 pollution”. I have read about “light pollution” over urban areas and assume this is an apt analogy. Let’s face it, even a good thing in larger than normal amounts over extended time can serve to “pollute” the normal stasis. I seem to recall reading that if we were subjected to pure oxygen it would have a deadly effect. It’s all relative. But we are still faced with how to deal with a very real problem. What strikes me as ironic is that some people were proposing a while back to “inject” co2 into deep pockets of ocean in order to trap it and get it out of the atmosphere, thereby reducing the greenhouse effect. Guess someone will have to rethink that approach.
AWB
18. gareth moore | 10.19.08
what the writer meant was ‘CO2 increase’ and this increase, as in any situation based chemical interaction, has an effect. The article deals with potential deleterious changes to the existing organic balance. Don’t fuss over one single semantic tree and not notice the changes to the ecological forest.
19. Ricksphd | 10.19.08
George, I think when the author is calling CO2 “pollution”, he is referring to CO2 that man has released into the atmosphere at an accelerated rate compared to “pre-man” eras. That seems like an appropriate term in this case, but your point is well taken.
20. Sean | 10.19.08
Laurie, claiming knowledge about what role God plays in all of this - i.e. claiming that an omnipotent force would never allow us to alter the world beyond some “acceptable” point and that “things will be alright” - is about as useful as blindfolds on a construction site.
We may not destroy the earth, but I’m sure we can make life on it very, very hard. With or without a surplus of spiritual romance.
21. Chris G | 10.22.08
Marwan, you figures are nonsense. If you add heat energy to a system, it can be measured immediately; it may be a while before heat introduced at the surface can be measured at the depths. And nobody said “runaway”; it will not be, but that does not mean it is not dangerous. Secondarily, you fail to understand the difference between CO2 cycling around the system and CO2 being added to the system.
Timothy, it is not a question. Here is a starter link
22. Marwan Nusair | 10.28.08
Chris, The heat energy required to expand the oceans and raise sea level takes 800 years to do. Surface temperature goes up and, indeed, is immediately measurable. A rise in ocean level requires a temperature increase in the bulk of the ocean, not just a thin layer at the surface, and it is that which takes centuries to see. So ocean levels today, I repeat, have to be due to heat input 800 years ago.
As for “runaway”, that is not my usage, but that of the alarmists. The common term they use is “tip-over point”, which is nonsense.
23. Marwan Nusair | 10.28.08
I should have also added that because a web site is called “real climate” does not necessarily mean that it’s “real” climate. James Hansen’s “hair on fire” views are well known.
24. Flouncer | 11.03.08
Can one of you with the understanding and qualifications please provide a link to information on controlled experiments, using the Scientific Method, illustrating the effect increases of CO2 from pre human concentrations to current times has ? i.e. show how an atmosphere with 380 ppmv can behave differently than one with 280 ppmv ? Also, I have seen a summary, a chart with no sources, showing that the effect of increasing CO2 concentration in the atmosphere is logarithimic. The effect of this characteristic is that initial increases of CO2 have a much greater effect than later, more concentrated ones. An increase of 20 to 40 ppmv, is much greater than the increase from say 330 to 380 ppmv. I would appreciate any information using laboratory or scientific testing, not modeling, that can prove or disprove these postulates.
Regards, Flouncer
25. Marwan Nusair | 11.10.08
Flouncer, The “logarithmic” effect to which you refer is also called the “tip-over point” and is supposed to result from positive feedback. Namely, CO2 caused heating, heating causes more water vapor, water vapor is a very efficient greenhouse gas and causes more heating, more vapor, more heating, ….. soon: hair on fire. Since temperatures were higher than they are now (for example, around 900-1000AD) and yet they cooled considerably around 1500-1800AD, that shows that an increase in temperature, for whatever reason, does not result in an unstoppable “logarithmic” increase. Obviously, it has happened before and appears to be part of a complex cycle.
In addition, CO2 only absorbs limited wavelengths of infrared, unlike water, so an increase from present levels would result in almost negligible increases in absorption and heating.
“Logarithmic” is probably not the correct description, mathematically, but I know what you mean.
Trackbacks/Pingbacks
Leave a Comment
We do not publish all comments, and we do not publish comments immediately. The comments feature is a forum to discuss the ideas in our stories. Constructive debate - even pointed disagreement - is welcome, but personal attacks on other commenters are not, and will not be published.
Tip: Do not write a novel. Keep it short. We will not publish lengthy comments. Come up with your own statements. This is not a place to cut and paste an email you received. If we recognize it as such, we won't post it.
Please do not post any comments that are commercial in nature or that violate copyrights.
Finally, we will not publish any comments that we regard as obscene, defamatory, or intended to incite violence.
1. George | 10.17.08
The article calls Co2 a pollutant. In no way shape or form is CO2 a pollutant. It is found in nature (and found at different levels in the atmosphere throughout earth’s history) and is essential for life on this planet. Calling CO2 a pollutant is like calling water vapor (the most powerful greenhouse gas) a pollutant.