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/
Need… more… input… beeep!
Interesting – a new source of vertical mixing?
It is really nice to see some genuine climate science in process. When there is a climate science worthy of the name, it will contain the results of millions of experimental efforts of data collection such as this. This team, maybe with the help of others, might actually come up with physical hypotheses which describe the regularities that make up this process of “mixing” in the oceans. Climate science, when it exists, will consists of many such hypotheses that have proved to be reasonably well confirmed.
If we knew the alleged pH change, the depth over which it has changed, then we could determine the amount of CO2 dissolved into the ocean since the Garden of Eden had the snake problem. Then, with the additional CO2 in the atmosphere, we could know whether the amounts jivved with the CO2 from fossil fuel burning. Bet there is too much CO2 to be accounted for …..
Surely this is just wind, ie weather, not climate. So CO2 is still evil. right? /sarc
Which might explain why these zones are associated with dense biologics.
A conspicuous omission on this blog: the radiation coming from Fukushima. Home come?
REPLY: We’ve covered it in detail, use the search box – Anthony
How come? Not home come . . .
“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.”
So if they don’t know how much CO2 is being mixed, how can he say that the oceans absorb 30%? Is this the best guess prior to this research? Or is this the guess that is used in climate models?
I am willing to bet the models understate how much is absorbed by the ocean, and that the modelers ahve nto incorporated the last few decades of research into this. They have a model that ‘fits’ and don’t adjust the model for scientific discoveries.
With regards to geoengineering I have mentioned the law of unintended consequences many times. The study, presented at the European Geosciences Union, should act as a warning to Warmists to steer clear over things they know little about.
If the theory didn’t correctly predict this, then is the theory falsified?
If observations don’t match predictions the predictions (theory) is wrong.
This is so simple that a child can understand it.
I just hope that these scientists make their raw data available before someone from GISS gets their grubby little paws on it in order to “homogenise” it.
Excellent report. As I have said many times here at WUWT, the modeling of the ocean for heat transfer and CO2 transfer is the key to debunking the AGW theory. As with the CO2, the heat from the surface is also wicked from the surface as the turbulence brakes down the Bernoulli layers. How much excess atmospheric heat is then caught in the immense heat sink that are the Earth’s oceans?
My guess is enormous amounts.
Addendum to my previous comment. I would also like to note this 3rd dimensional mixing and energy transition boundary increases the ‘surface area’ of the heat and CO2 in the oceans. Now the boundaries are not just the sea surfaces and the small upper layers of water. Just as pebbles have much more surface area as a single rock in the same volume, the heat and CO2 transport paths have just increased by many orders of magnitude beyond anything I would wager was previously ‘modeled’ (more like badly guessed at).
Well as I have opined on quite a few occasions, here at wUWT, there is a quite natural pumping process, for depleting the ocean surface of CO2 and pumping it to the ocean depths.
It is called “concentration gradient diffusion”
As is well known CO2 is more soluble in colder water, and equally well known is that the normal ocean is mostly warmer at the surface, and gets colder as you go deeper. If it didn’t do that, then the the less dense colder water would rise to the surface. Well it doesn’t because salt water gets denser as it gets colder right down to the freezing point, so long as the salinity is greater than about 2.47% salts. Ocean water is typically 3.5% salts, so it is always denser at lower temperatures.
Every scuba diver knows that the water gets colder as you descend from the surface, until you reach some sort of thermocline, or inversion layer, and after that it apparently keeps on getting colder, but at a slower rate.
In any case, in the upper layer, any thin water layer, has a colder denser layer below it, and a warmer less dense layer above it, so the CO2 in our layer is less soluble in the upper layer, and more soluble in the lower layer, so you have a natural segregation of the CO2 between the layers, as CO2 molecules are much more likely to stay in the lower colder layer, than to move to the warmer upper layer, so CO2 is continuously diffusing down to the colder waters; thereby depleting the surface layer; and then Henry’s law drives in more CO2 from the atmosphere.
By the same token, when the ocean surface gets heated by LWIR, it is less likely to outgas CO2 since the surface layer is depleted of CO2 by the downward diffusion, so if the surface heats (from LWIR absorption) there isn’;t much of a CO2 sink below it to keep supplying CO2 to outgas.
So significant CO2 outgassing from the ocean would normally require some significant turnover process, that brings deeper CO2 laden water to the surface.
So I’m not surprised that ocean turbulent flows are involved in CO2 mixing.
Now my arm waving analysis, is qualitative only; I’ll leave it to research granted PhDs to falsify, or perhaps provide the quantitative underpinnings, for support.
wow … basically they just threw out their old theories … this new data killed them … which means prior to this THEY DID’NT KNOW what they where talking about, they were guessing without real data … prior to this they apparently weren’t doing much science, playing with numbers and statistics doesn’t make it science or you a scientist, now playing with observed data, that is science by scientists …
When the really big boats travel over the open ocean, how much CO2 is released from the hot water expelled from the engine cooling system?
I am very sorry but I think the spanner in my pocket is going to drop into the works here.
Atmospheric Carbon Dioxide knows that it has no business bathing in the oceans. CO2 does not mix with water. 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.
Alternatively you can open a can (or bottle) of beer or ‘pop’ and ask yourself “why are all these bubbles wanting to get out?
If you really want the beer or ‘pop’ to absorb the CO2 completely then vigorously shake the can before opening.
However having said that, if there are seemingly reasonable people who believe that the product of energy-use which is heat, is a form of energy creation that warms this planet of ours then how can I blame them for thinking that gases in the atmosphere are determining the structure of waters in the Oceans?
Oh and Harold Pierce Jr., you ask on April 15, 2011 at 2:48 pm: “
When the really big boats travel over the open ocean, how much CO2 is released from the hot water expelled from the engine cooling system?”
The answer is: ‘probably not any more than from any cold water that surrounds it as the CO2 is released (usually through the funnels) from the carbon fuels used to heat the water in the first place’
AJStrata says:
April 15, 2011 at 12:26 pm
Excellent report. As I have said many times here at WUWT, the modeling of the ocean for heat transfer and CO2 transfer is the key to debunking the AGW theory. As with the CO2, the heat from the surface is also wicked from the surface as the turbulence brakes down the Bernoulli layers. How much excess atmospheric heat is then caught in the immense heat sink that are the Earth’s oceans?
My guess is enormous amounts.
_____
The issue of how both CO2, and LW radiaiton (i.e. heat), can get actually get mixed into the deeper layers of the ocean has long been modelled to occur is some turbulent way, but this actual observation helps to put some real numbers on the theory. It has long been known that the majority of both the heat and the anthropogenic CO2 must be going into the deeper ocean layers, and some sort of turbulent mixing must be the cause. It is nice to see data and observation back up (and we can hope) help advance theory and the GCM’s they support.
A very interesting post.
It seems to pass the logic test by explaining the physical processes in a manner that makes common sense.
It’s not understanding each individual process that is most important, but how they all interact in the physical world to produce a nett result.
That is something that appears to be lost on many pro AGW’ers who focus on individual theoretical processes to sustain their beliefs rather than the overall, but very complex logistics involved.
“Theodore says:
April 15, 2011 at 11:22 am
So if they don’t know how much CO2 is being mixed, how can he say that the oceans absorb 30%?”
“I am willing to bet the models understate how much is absorbed by the ocean,”
With respect to the first point, we have a rough idea how much CO2 man puts into the air via the burning of fossil fuels, however the concentration in the air only increases at about half that rate. So the other half has to go somewhere. A good portion of the CO2, perhaps 15%, goes into increased photosynthesis, so the rest has to be absorbed by the oceans.
As for the second point you raise, I see no incentive for them to “understate how much is absorbed by the ocean”. They also like to scare us with ocean acidification so the more CO2 that gets absorbed into the ocean, the more acidic the ocean becomes.
But having said the above, there are major problems: The extra CO2 in the air is not causing any warming and the extra CO2 in the oceans is not causing any acidification to be worried about. The pH may drop a slight amount, but it will always be well into the basic range.
The block diagram shown above looks just like the one out of the UK Open University course book fromS330 Oceanography. So old science then not a new discovery.
I think they need to put these people on the Blacklist!
After all, they are undermining “the concensus”; “The Science is Settled”. Right?