From the University of Washington via Eurekalert
Data catches up with theory: Ocean front is energetic contributor to mixing
Wind blowing on the ocean is a crucial factor mixing the greenhouse gas carbon dioxide into the ocean depths and keeping it from going back into the atmosphere.
For more than two decades scientists have suspected there’s another – possibly substantial – source of energy for mixing that’s generated in the ocean where cold, heavy water collides with warm, light water. However, there’s never been a way to get enough measurements of such a “front” to prove this – until now.
University of Washington and Stanford University researchers report in the print edition of Science April 15 about turbulence at a front near Japan that is 10 to 20 times more energetic than what the wind could generate.
Without such data, the turbulence and mixing contributed by fronts can’t be reliably accounted for in climate models, according to Eric D’Asaro, oceanographer with the UW Applied Physics Laboratory and School of Oceanography. Climate modelers, for example, need an accurate reading of how rapidly carbon dioxide is mixed into the depths, or interior, of the ocean in order to use the models to predict the effects of climate change, he says. Right now, for instance, the oceans absorb about 30 percent of the carbon dioxide released into the atmosphere.
“Progress in understanding the dynamics of fronts has been hampered by lack of observations,” says Raffaele Ferrari, Massachusetts Institute of Technology professor of oceanography, who is not involved with the paper.
“The research represents a remarkable breakthrough in that it provides possibly the first direct observations of how an ocean front works on scales from kilometers to millimeters,” Ferrari says. He’s the author of a “Perspectives” piece in Science April 15 about the challenges of representing oceanic fronts in climate models.
Thousands of fronts develop in the ocean where bodies of water with different characteristics meet. Typically one is colder and the other warmer: think of river water flowing into the ocean, or ocean currents from the tropics encountering those from the poles. Fronts can be small, stretching only hundreds of yards while others go on for miles; some exist only briefly while others persist for weeks or months; and the path of a front is continually meandering.
The ever-changing position and shape of fronts is what makes them devilish to measure.
“It’s like trying to watch a tadpole grow while it’s being carried downstream in a river,” says Craig Lee, oceanographer with the UW Applied Physics Laboratory and School of Oceanography and a co-author of the paper. “You can’t expect to sit in one place and watch it turn into a frog – you have to follow it wherever it goes.”
D’Asaro, Lee and their colleagues picked the Kuroshio front off Japan for their attempt. The Kuroshio current, second in strength only to the Gulf Stream, carries warm water north from the subtropics and forms a front where it meets cold subpolar water carried south by the Oyashio current.
Although the front is strong and persistent, the scientists had to choose one particular piece, continually track its exact location as it was carried downstream and measure it. Floats developed by D’Asaro, which are programmable and buoyant in a way that they can stick with a moving and undulating body of water, marked the location of the chosen section and relayed acoustic signals so a ship could go to the front and measure what was happening.
At the Kuroshio front, winds blowing along the front combined with the Earth’s rotation create currents that flow across the front pulling cold water over warm. Cold water is heavier than warm water and turbulence is created as the top-heavy waters sort themselves out, creating new, more-temperate layers of warm on top of cold water.
The work involved “a great deal of ingenuity to keep all these tools along a front for a few weeks,” Ferrari says.
What they found at the strong Kuroshio front, D’Asaro says, is likely an extreme example of a process that occurs much more widely in the ocean.
“It’s not just wind at work on the ocean. The enhanced mixing at this front is drawing energy from the entire North Pacific. That’s what’s really new,” D’Asaro says.
It would be useful to measure other fronts, such as those associated with the Gulf Stream and Antarctic circumpolar currents, to further define their role in ocean dynamics and climate models, Lee says.
Along with D’Asaro and Lee, other co-authors are Luc Rainville and Ramsey Harcourt with the UW’s Applied Physics Laboratory, and Leif Thomas with Stanford University. The work was funded by the Office of Naval Research.
For more information:
D’Asaro, 206-685-2982, dasaro@uw.edu
Lee, 206-685-7656, craig@apl.washington.edu
Ferrari, 617-253-1291, rferrari@mit.edu
Suggested websites
Science abstract http://www.sciencemag.org/content/early/2011/03/09/science.1201515
D’Asaro website http://opd.apl.washington.edu/~dasaro/HOME/index.html
D’Asaro float technology http://opd.apl.washington.edu/~dasaro/FloatTech/floats.html
Craig Lee website http://iop.apl.washington.edu/people.html
Triaxus technology http://iop.apl.washington.edu/tools.html
UW Applied Physics Laboratory http://www.apl.washington.edu/
UW School of Oceanography http://www.ocean.washington.edu/
MIT’s Raffaele Ferrari http://web.mit.edu/raffaele/www/Home.html
Kuroshio current http://www.encyclopedia.com/topic/Kuroshio_Current.aspx
UW’s Luc Rainville http://www.apl.washington.edu/people/profile.php?last=Rainville&first=Luc
UW’s Ramsey Harcourt http://www.apl.washington.edu/people/profile.php?last=Harcourt&first=Ramsey
Stanford U’s Leif Thomas http://pangea.stanford.edu/~leift/
Office of Naval Research http://www.onr.navy.mil/
Very amusing, Dahlsveen!
As the dry ice in an inkwell obviously has nothing to do with anything here.
And your soda/beer analogy is exact opposite of the physical mechanics that we all know.
Shaking tends to separate, while tapping on the container tends to re-integrate the CO2 into the liquid.
So I must assume you meant to ‘spoof’.
George E. Smith says: April 15, 2011 at 1:35 pm
I agree with your assertion of the thermal gradient and the attributes you describe. I would also add that the gradient of CO2 concentration would follow a natural log curve that describes diffusion, enhanced by the cooler water’s capacity to hold more gas.
I would wonder how much of this is a one-way process. Two years or more someone posted here about deep sea pressure causing unusual chemical processes that incorporated CO2 into solid minerals that precipitated out of the water.
Mixing of bottom currents with top currents does not occur unless there is a difference in content between one layer and the other. Hence, ocean fronts may only cause mixing on the surface in some areas. In other words, ocean fronts are not a pre-condition for influencing weather and climate globally.
pettyfog says April 16, 2011 at 7:55 am:
“- – – – – -. So I must assume you meant to ‘spoof’.”
You may take it as a ‘spoof’ if you like pettyfog but I was trying to show how unlikely I think it is that CO2 is going to mix with (and therefore be absorbed by) any turbulent ocean surface.
You also say: “Shaking tends to separate” – so, if you know that turbulence within a container with a liquid/CO2 mixture tends to separate the two then why do you accept that a turbulent ocean surface is more likely to absorb more CO2?
Further you say: “And your soda/beer analogy is exact opposite of the physical mechanics that we all know.”
That is the only “analogy” of the behavior of CO2 in water that I know of, and you are right, it is the exact opposite to the – – – – – – .
I know it can be done with a pen and paper thus: “CO2 (aq) + H2O ↔ H2CO3 ↔ HCO3- + H+ ↔ CO32- + 2 H+” (just like Wikipedia does it. Sorry but this formula has lost a bit of its clarity due to circumstances beyond my control.) – But since you are the one who state that this is “the physical mechanics that we all know” you must be the one most able to tell me how we can do (or perform) an experiment that proves the theory that CO2 is being dissolved into the oceans. – The theory also states, by the way that “all gases can be dissolved in water” and Wikipedia goes on to say: “Oceans are at present CO2 sinks, and represent the largest active carbon sink on Earth, absorbing more than a quarter of the carbon dioxide that humans put into the air.”
This is nothing short of amazing information in-as-much-as not only are the oceans selective and just interested in absorbing the carbon dioxide that humans put into the air but it only happens “at present” and may therefore be expected to change at any time, – or as soon as the warming oceans temperature card is played.
In the article above D’Asaro says: “The enhanced mixing at this front is drawing energy from the entire North Pacific. That’s what’s really new,”
So, apart from that, there is nothing new about what I see as theory and which you obviously think of as factual physical mechanics.
I have got a feeling much more funding is needed for science to be able to get to the bottom of this ‘fact or fiction’ problem.
Carbon Dioxide readily mixes with water, (as it does in the atmosphere and comes down in rain), so what are they measuring?
O H Dahlsveen says:
April 15, 2011 at 2:58 pm
Atmospheric Carbon Dioxide knows that it has no business bathing in the oceans. CO2 does not mix with water.
? Carbon Dioxide readily mixes with water in the atmosphere to come down in rain as Carbonic Acid. Even if it didn’t, it is 1.5 times heavier than the gas Air mainly Nitrogen and Oxygen which comprise our atmosphere, it will always, therefore, tend to sink down through Air, displacing it. It has every business bathing in water, not just in rain, but in the oceans, to get to where it is required for life, where it is food.
You can learn this fact by throwing a small bit of ‘Dry Ice’ (frozen CO2) into an inkwell in which case you will understand what rejection means by the time you have cleared up the mess.
Don’t know what you are describing here, but here’s how Disappearing Ink Works – http://chemistry.about.com/od/demonstrationsexperiments/ss/disappearink_2.htm
Or, is it a variation of this, dry ice fog? – http://physics.about.com/od/halloweenphysics/f/DryIce.htm
Myrrh says April 17, 2011 at 5:34 pm:
“? Carbon Dioxide readily mixes with water in the atmosphere to come down in rain as Carbonic Acid.”
Carbonated water has got many names Myrrh but rain water is a new one on me.
Names like; soda water, sparkling water, seltzer, or fizzy water are all descriptions of types of water into which carbon dioxide (CO2) gas has been ‘dissolved’ under pressure. – upon releasing the pressure, the gas leaves the liquid with a hissing sound and as bubbles form in the liquid…. The speed at which the gas leaves is dependant upon things like water- temperature and surface area open to atmosphere.
Yes I will admit that CO2 in water does have some reaction and will form a weak solution of Carbonic acid, which gives the water the ‘tingly’ taste on the tongue you get from carbonated water.
And yes CO2 is a heavy gas but it is a heck of a lot lighter than sea-water. – ‘Acid Rain’ is not a water/CO2 mixture. Acid Rain is more likely to be the result from atmospheric soot particles mixing in with the rain drops. –
You may as well face it Myrrh; CO2 is a stage or phase in the carbon cycle. Only after the Flora has ‘Photosynthesized’ or split CO2 back to its original two parts Carbon (sugar) and Oxygen can we say that the C in CO2 is on its way back to the sea.
CO2 (and other gases) are produced in the oceans, maybe more so than on land and the idea that Anthropogenic CO2 is being absorbed by the oceans and thus destroying the life in them is an AGW myth to make people despair and join in the pollutant chorus.
Why do you think CO2 is used for extinguishing electrical fires???????? – Because CO2 repels water!!!!! – That’s why.
Reply: Uh, CO2 does not “repel” water, it is used in electrical fires because it does not contain water and does not induce short circuits. Dry chemical fire extinguishers are also appropriate for electrical fires. Acid rain is a debated and complex subject, but was purported to be caused by atmospheric sulphur from industrial emissions. ~ ctm
“”””” Steve Keohane says:
April 16, 2011 at 8:14 am
George E. Smith says: April 15, 2011 at 1:35 pm
I agree with your assertion of the thermal gradient and the attributes you describe. I would also add that the gradient of CO2 concentration would follow a natural log curve that describes diffusion, enhanced by the cooler water’s capacity to hold more gas.
Well I’m less familiar with diffusion in liquids, but for solid state diffusion the concentration versus depth, resulting from an external (atmospheric) source follows the Complementary Error Function C(x,t) = Cs.erfc(x/2sqrt(Dt)). (t) is time, and (D) is diffusion coefficient, for the species.
The process in solids still follows Henry’s Law, so I wouldn’t be surprised if erfc is not the depth – time function in liquids as well.
The surface concentration (Cs) is a function of the segregation coefficient, and the atmospheric concentration. In semiconductor diffusion processes, this source concentration is normally maintained throughout the so-called pre-deposition (pre-dep) phase; which is foreve in the atmospheric/ocen case. In SS technology, the pre-dep is terminated, and the escape of the diffused species is cut off by a blocking layer (oxide or nitride, or more exotic layer); while a second “drive in” diffusion step is poerformed. That results in the surface concentration dropping, as the dopant proceeds deeper, and, the doping profile morphs into a Gaussian form. Andy Grove (of Fairchild, and Intel) Physics, and Technology of Semiconductor Devices, is still a standard reference on solid state diffusion and related Semi-conductor technology. Of course today, things are more complicated, since Ion Implantation has replace a lot of classical diffusion processes; at least in the pre-dep phase.
I was fortunate enough to get my Solid state Physics foundation from Andy Grove and others while he and the Intel founders, were all still at Faichild Semiconductor. For some strange reason Grove chose to give the device electrical noise theory part of the course; rather than the SS-Diffusion part, and he got it all wrong; even continued to swear by a noise formula for Bi-polar transistors, that wasn’t even dimensionally balanced. That was no impediment to Andy accepting the result; which absolutely nobody in the class even recognized; because it resulted from a simplifying assumption that would never be valid, in any practical case of design for low noise. A class mate called him on it; and he just sloughed it off. But his book is still the best on the subject.
That step would seem to be absent from the atmospheric/oceanic diffusion case; which is further complicated by the Temperature decline, and its resultant higher CO2 solubility (segregation coefficient.)
In any case, I see CO2 being pumped endlessly into the depths, rather than remaining at the surface; so when a surface warming occurs, which outgases CO2, that is a transient phenomenon, since the surface layer will be depleted of CO2, quickly, and resupply from the depths, will be awfully sslow, sans overturning turbulence. Back diffusion from the depths, will not keep supplying a surface outgqassing, due to a surface heating transient; such as the absorption of LWIR energy in the top few microns.
If anyone is interested in reading more on this topic, see http://www.telegraph.co.uk/earth/earthnews/6538300/Climate-change-study-shows-Earth-is-still-absorbing-carbon-dioxide.html
One sentence in this site says: According to the study, the Earth has continued to absorb more than half of the carbon dioxide pumped out by humans over the last 160 years.
O H Dahlsveen says:
April 18, 2011 at 1:33 pm
Carbonated water has got many names Myrrh but rain water is a new one on me.
Why am I not surprised? AGWScience has a lot to answer for..
http://www.gcsescience.com/w2-carbon-cycle.htm
Do ignore the milksop to AGW re burning of fossil fuels, but the rest is OK. This is the bog-standard knowledge about Carbon Dioxide, called the Carbon Cycle (cf the Water Cycle).
“Carbon Dioxide in the atmosphere dissolves in rain water, forming carbonic acid (H2CO3). This makes rain water naturally acidic (pH=5.5). … Rain water finds its way into the sea. Carbon dioxide also dissolves directly into the sea.”
That’s one way that Carbon Dioxide does not stay up in the atmosphere for the claimed “hundreds and thousands of years accumulating”, it very readily mixes with Water in the atmosphere to form Carbonic Acid to come back down to Earth where it is food for plants etc.
The other way it comes down is because it is heavier than Air, it will always sink through the gas Air displacing it, because that’s what heavier than Air things do. It can’t defy its own weight re Air; wind can move it around as it will be subject to greater forces acting on it such as the changes in air pressure, but it’s not always windy.. Again, coming down to Earth to be used in the Food Chain.
Something that I spotted recently, but didn’t have time to read the article, was that some are using dry ice to seed clouds to create rain.
Thanks Mod for the electric fire info. Carbon Dioxide is also good for any kind of fire, because it is heavier than Air it displaces it and becomes a fire-blanket, starving the fire of Oxygen.
Anyway, all rain is naturally acidic especially because of its propensity to pick up the Carbon Dioxide in the atmosphere around it.
http://www.chemistry.wusti.edu/~edudev/LabTutorials/Water/FreshWater/acidrain.html
Again, just ignore the AGW scaremongering.. they’ve really no sense of proportion.
Reply to my comment on April 18, 2011 at 1:33 pm by ~ ctm which partly was:
“Uh, CO2 does not “repel” water, it is used in electrical fires because it does not contain water and does not induce short circuits”
Quite right, “repel” was the wrong word to use and I should perhaps have used the term; ‘does not mix with’. However you may be the right person to ask how to perform an experiment that proves that I am wrong and that CO2 does indeed mix with water in “the open air” or in other words ‘outside of the restrictions of a container and under normal atmospheric pressure conditions’ – If you can, then I shall change my mind and accept the claim that the atmosphere is also capable of ‘singling out and absorbing’ Anthropogenic Carbon Dioxide (ACO2)
PS.
I have never claimed CO2 to be the ‘only medium’ that can be used to extinguish electrical fires. – By the way, in my experience there has never been much point in putting such fires out unless the power supply is turned off first. – In which case, outside, on a dampish day CO2 is the one to use as it has less of a chance of going ‘lumpy’
And yes, you are right about Acid Rain.
Werner Brozek says April 18, 2011 at 7:24 pm:
“If anyone is interested in reading more on this topic, see – – – – -. One sentence in this site says: – – – – “
Another sentence, or more, says: “”Like all studies of this kind, there are uncertainties in the data, so rather than relying on Nature to provide a free service, soaking up our waste carbon, we need to ascertain why the proportion being absorbed has not changed,” he said.”
Looks (to me) like more funding is needed here.
George E. Smith says: April 18, 2011 at 3:35 pm
“”””” Steve Keohane says: April 16, 2011 at 8:14 am
George, my IC experience is mostly in phot0lith, helping to wrangle it from the level of ‘black art’ to a measured science starting in ’71. I was thinking of the concentration curve of diffusion diminishing at a natural log rate from the source. It seems to me the inverse would be situation here, where the colder water is analogous to the N2 trap in a vacuum chamber, sucking in any available molecules. I am agreeing with you if it is not clear.
Myrrh says on April 19, 2011 at 3:28 am:
Again, just ignore the AGW scaremongering.. they’ve really no sense of proportion.
Hehe- he. – You are mistaking me for a AGW scaremongerer!
Do you really not understand that the”Bog Standard Carbon Cycle you are describing is produced by the global warming and greenhouse gases people who are the very people doing all the AGW scaremongering? All I ask you to do is to question the science that you have been accustomed to call “bog standard”
You seem to have no problem with accepting this particular part of the CAGW theory, i.e. that anthropogenic CO2 (ACO2) is readily absorbed by the oceans. I therefore hereby challenge you to explain how to perform an experiment that proves that CO2 does mix with water in “the open air” or in other words ‘outside of the restraints of a container and under normal atmospheric pressure conditions’
Do believe me Myrrh when I tell you that the idea that the oceans preferably select man made CO2 for absorption so that that kind of CO2 can ruin corals and cru stations are not quite right. I for one need proof before I – like you (maybe unintentionally) – help spreading the AGW scaremongering.
? Shrug. I really can’t help it if AGW have nightmares about acid and the food Carbon Dioxide. This is the bog standard teaching of traditional science, Carbon Dioxide readily mixes with water to come down in rain and it’s all GOOD. We evolved as we are, life on earth, because these things happen. UV is not a bugbear causing cancer, it is essential for Vitamin D formation. There are cases now of rickets in the West when it had been eliminated because of improved diet. Why? Because the SUN is something to be frightened of, and unless Factor 168 at least you’ll die from cancer of skin…
I cannot be held responsible for other people’s nightmares which are produced by their own high priest’s propaganda. The science doesn’t change. Either something is a fact or it isn’t.
The Water Cycle washes the atmosphere clean. How? By forming around particles in the Air, and, in that cycle we also get disinfected… How’s that for taking away the nightmares? Carbon Dioxide the Natural Disinfectant.