![screenshot_wave_graph[1]](http://wattsupwiththat.files.wordpress.com/2013/09/screenshot_wave_graph1.jpg?quality=83 "Posts by Hannah Hickey")
Waves breaking over sandy beaches are captured in countless tourist photos. But enormous waves breaking deep in the ocean are seldom seen, although they play a crucial role in long-term climate cycles.
A University of Washington study for the first time recorded such a wave breaking in a key bottleneck for circulation in the world’s largest ocean. The study was published online this month in the journal Geophysical Research Letters.
The deep ocean is thought of as dark, cold and still. While this is mostly true, huge waves form between layers of water of different density. These skyscraper-tall waves transport heat, energy, carbon and nutrients around the globe. Where and how they break is important for the planet’s climate.
“Climate models are really sensitive not only to how much turbulence there is in the deep ocean, but to where it is,” said lead author Matthew Alford, an oceanographer in the UW Applied Physics Laboratory. He led the expedition to the Samoan Passage, a narrow channel in the South Pacific Ocean that funnels water flowing from Antarctica.
“The primary importance of understanding deep-ocean turbulence is to get the climate models right on long timescales,” Alford said.
Dense water in Antarctica sinks to the deep Pacific, where it eventually surges through a 25-mile gap in the submarine landscape northeast of Samoa.
“Basically the entire South Pacific flow is blocked by this huge submarine ridge,” Alford said. “The amount of water that’s trying to get northward through this gap is just tremendous – 6 million cubic meters of water per second, or about 35 Amazon Rivers.”
In the 1990s, a major expedition measured these currents through the Samoan Passage. The scientists inferred that a lot of mixing must also happen there, but couldn’t measure it.
In the summer of 2012 the UW team embarked on a seven-week cruise to track the 800-foot-high waves that form atop the flow, 3 miles below the ocean’s surface. Their measurements show these giant waves do break, producing mixing 1,000 to 10,000 times that of the surrounding slow-moving water.
“Oceanographers used to talk about the so-called ‘dark mixing’ problem, where they knew that there should be a certain amount of turbulence in the deep ocean, and yet every time they made a measurement they observed a tenth of that,” Alford said. “We found there’s loads and loads of turbulence in the Samoan Passage, and detailed measurements show it’s due to breaking waves.”
It turns out layers of water flowing over two consecutive ridges form a lee wave, like those in air that passes over mountains. These waves become unstable and turbulent, and break. Thus the deepest water, the densest in the world, mixes with upper layers and disappears.
This mixing helps explain why dense, cold water doesn’t permanently pool at the bottom of the ocean and instead rises as part of a global conveyor-belt circulation pattern.
The Samoan Passage is important because it mixes so much water, but similar processes happen in other places, Alford said. Better knowledge of deep-ocean mixing could help simulate global currents and place instruments to track any changes.
On a lighter note: Could an intrepid surfer ride these killer deep-sea waves?
“It would be really boring,” admitted Alford, who is a surfer. “The waves can take an hour to break, and I think most surfers are not going to wait that long for one wave.”
In fact, even making the measurements was painstaking work. Instruments took 1.5 hours to lower to the seafloor, and the ship traveled at only a half knot, slower than a person walking, during the 30-hour casts. New technology let the scientists measure turbulence directly and make measurements from instruments lowered more than 3 miles off the side of the ship.
The researchers left instruments recording long-term measurements. The team will do another 40-day cruise in January to collect those instruments and map currents flowing through various gaps in the intricate channel.
Co-authors of the paper are James Girton, Gunnar Voet and John Mickett at the UW Applied Physics Lab; Glenn Carter at the University of Hawaii; and Jody Klymak at the University of Victoria. The research was funded by the National Science Foundation.
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- Visit the Wavechasers website
- Watch the authors conduct research in Samoa
- Read the new research paper
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of course the Oceans are the key to climate…monsoon…enso…etc… are driven by ocean currents…if cold salty water sinks…it must displace something…circulation…the submarine guys…who one would think are the best informed about this stuff…dont go very deep…maybe 300 meters max…average depth of the oceans is about 4500 meters
izen says: September 11, 2013 at 3:19 am Re: speculation on deep ocean heat.
1. Measure it.
2. Report back when you have finished.
3. Don’t speculate.
Such a mechanism would be easily experimented with in a flume. Why are climate scientists so afraid of experimentation – we have to stop the silly baloney even supported by skeptics that the climate is so chaotic and can’t be experimented with. Although chaotic systems are apparently real, I’m afraid the relief this too broad an idea gives to the unimaginative is an impediment to science. I’m sure most of the systems branded chaotic are of the throw-your-arms-up variety and the chaos would largely disappear with more ingenuity (and the knowledge that can be gleaned):
https://www.google.ca/search?q=laboratory+flume&client=firefox-a&hs=e4j&rls=org.mozilla:en-US:official&tbm=isch&tbo=u&source=univ&sa=X&ei=-FIwUrroEOqY2gWygYHAAg&ved=0CCwQsAQ&biw=853&bih=435
The flume: you could dye the high-salt water a different colour and you won’t have such arduous journeys as a 40 day trip to Samoa! You could even use a range of densities for the heavier fluid to see variations in the efficiency of the effect. I’m a little suspicious of the waves breaking dramatically in a slow moving pulse. They would most likely maintain a smooth profile. How much turbulence is there in a bulging pipe with slow movement of the fluid? Also, they measure this at a three mile depth. How thick is this layer? If you have to voyage all the way to Samoa to do this research and you need the precise conditions of two parallel ridges a certain distance apart for this to happen with 6 km^3 s^-1 of water, How representative of this condition is it for the other 99.99% of the cold salty water flow from both poles? Do the flume tests and get back to me on this.
@- richardscourtney Re:- thermal expansion of the oceans.
“The unavoidable reality is that there are no measurements with sufficient accuracy to support your untrue assertion.”
The unavoidable reality is that the field of geology considers that it CAN measure the thermal expansion of the oceans quite adequately. While there are various aspects of science that are difficult or open to interpretation, the measurement of sea level rise is an objective physical measurement that can be determined by multiple methods, all of which give consistent results.
Claiming that geologists and oceanographers {not climate scientists} are incapable of making the measurements they report and must therefore be lying when they report the accelerating rise in sea levels would seem to put you in the position of rejecting another whole branch of the physical sciences.
Or perhaps you are implying that the scientists who report the rising sea level are acting in a fraudulent manner and are inventing the measurements to be consistent with the climate field?
http://sealevel.colorado.edu/
Thanks for that remembrance. Still hard to look at those images, but great song by Alan Jackson.
/Mr Lynn
I don’t really understand why water needs to move to transport heat. Water is quite conductive to heat. Certainly mixing will accelerate the process, but the notion that heat could be “sequestered” under the ocean seems patently ludicrous.
The eighth figure in this post:
http://astroclimateconnection.blogspot.com.au/2011/11/el-ninos-and-extreme-proxigean-spring.html
gives some idea of the extent of world-wide cool deep water mixing that is caused by lunar tides.
Studies of this tidal dissipation have been made in the Hawaiian Islands showing that ocean-bottom lunar tidal dissipation plays an important role in the up welling of deep ocean waters.
Three miles down, what’s the temperature difference between two water parcels only 800 feet apart vertically? The miniscule difference is going to matter to the models? Grasping at straws…
In our understanding of oceans, we are still at a level of gaining confidence in data through data collection and analysis.
For analysis, here is a recent paper:
http://pluto.mscc.huji.ac.il/~msdfels/wpapers/Tide%20gauge%20location.pdf
………………………….
From abstract,
Mean Sea Level (PSMSL) during 1807 – 2010 without recourse to data reconstruction. Although mean sea levels are rising by 1mm/year, sea level rise is local rather than global, and is concentrated in the Baltic and Adriatic seas, South East Asia and the Atlantic coast of the United States. In these locations, covering 35 percent of tide gauges, sea levels rose on average by 3.8mm/year. Sea levels were stable in locations covered by 61 percent of tide gauges, and sea levels fell in locations covered by 4 percent of tide gauges. In these locations sea levels fell on average by almost 6mm/year.
@joshv
>Water is quite conductive to heat.
Compared to what? Water is less conductive thermally than concrete or glass …
Glass,ordinary 0.8
Concrete 0.8
Water at 20° C 0.6
… and way less conductive than diamonds, the most thermally conductive substance known (thus explaining the nickname ‘ice’ for diamonds)
Diamond 1000
(units: watts per meter-Kelvin)
http://hyperphysics.phy-astr.gsu.edu/hbase/tables/thrcn.html
A perfect example of over thinking something you don’t know…
I live on Lake Champlain and it has been known for years that there are waves in the thermocline that move the thermocline up and down by something like 30 ft over a matter of hours. Because of the long narrow nature of the lake, they bounce back and forth. Sometimes they “break” against one end of the lake or another exposing the cooler water to the surface.
Here is a paper on it.
http://onlinelibrary.wiley.com/doi/10.1029/98JC01450/abstract;jsessionid=21D2385959CA6288F0AF24C789351E26.d02t04?deniedAccessCustomisedMessage=&userIsAuthenticated=false
The heat capacity of the oceans is 1000 times the heat capacity of the atmosphere. So if we would have warmed an additional 2C from GHG warming, but instead that heat went missing into the Oceans, then the Oceans are now 0.002C warmer. And guess what, the most warming that missing hear can now give back to the atmosphere is 0.002C So if the models
Sorry My comment was just this:
The heat capacity of the oceans is 1000 times the heat capacity of the atmosphere. So if we would have warmed an additional 2C from GHG warming, but instead that heat went missing into the Oceans, then the Oceans are now 0.002C warmer. And guess what, the most warming that missing hear can now give back to the atmosphere is 0.002C
I guess what is interesting about this is that by measuring this choke-point for deep ocean water flow, we can now say that the Antarctic Deep Ocean Water is actually flowing into the north Pacific.
Many of the Thermohaline Ocean Circulation models showed this to be occurring but there was no real evidence for it and no real place where they could say it eventually upwells/surfaces, hundreds of years later, after warming up from 0.0C to 12.0C for example. I always thought it was just theoretical because there was no real evidence for it while there was evidence for other Antarctic Deep Water upwelling areas.
Image of the region.
http://s21.postimg.org/bpif57con/Samoan_Passage.jpg
Google Maps link – just east of Tokelau. Choke point for deep ocean flow for thousands of kms to the west side of Australia.
https://www.google.ca/maps?ll=-15.834536,-177.84668&spn=31.668157,67.631836&t=h&dg=opt&z=5
There is a pattern appearing out of the noise again/still.
Official climate science comes up with a new hypothesis to explain some failure in the overall global warming hypothesis, in this case saying the missing heat is in the deep oceans.
Skeptics point out a weakness in the proposed hypothesis, in this case saying there is no mechanism for getting surface heat into the deep oceans.
Climate science apparatchik then pile in saving there is no weakness, in this case saying wave action, downwelling ocean currents take the heat down.
The discussion between skeptics and apparatchik devolves to name calling.
Official climate science comes up with a new hypothesis to explain some failure in the overall global warming hypothesis, in this case saying deep ocean mixing is carrying the heat into the deep oceans.
Etc.
This cycle continues in the discussions around UHI and the missing mid-troposphere heat.
At no point will anyone say, “Hey the skeptics were right!”
The most important thing this report presents is” That the science is not settled”!
There is no “credible experiment that proves that the hypothesis of the greenhouse gas effect exists”
There is an experiment that proves that the Greenhouse gas effect does not exist. This experiment which has been technologically reviewed by Ph.D physicists . Ph.D. Chemical engineers and others Ph. D’s in other fields The experiment is found on the web-site http:// http://www.slayingtheskydragon.com click on the blog tab then on page 3 of 12. . It is titled “The Experiment that failed which can save the world trillions-Proving the greenhouse gas effect does not exist”
The Greenhouse Effect Explored
Written by Carl Brehmer | 26 May 2012
Is “Water Vapor Feedback” Positive or Negative?
Exploiting the medium of Youtube Carl Brehmer is drawing wider attention to a fascinating experiment he performed to
test the climatic impacts of water in our atmosphere.
Carl explains, “An essential element of the “greenhouse effect” hypothesis is the positive “water vapor feedback” hypothesis. That is, if something causes an increase in the temperature this will cause an increase in the evaporation of water into water vapor.”
Another important website is www. The Great Climate Clash.com -G3 The Greenhouse gas effect does not exist.
Dr. Vincent Gray on historical carbon dioxide levels
Posted on June 4, 2013 by Anthony Watts
NZCLIMATE TRUTH NEWSLETTER NO 312 JUNE 4th 2013
CARBON DIOXIDE
There are two gases in the earth’s atmosphere without which living organisms could not exist.
Oxygen is the most abundant, 21% by volume, but without carbon dioxide, which is currently only about 0.04 percent (400ppm) by volume, both the oxygen itself, and most living organisms on earth could not exist at all.
This happened when the more complex of the two living cells (called “eukaryote”) evolved a process called a “chloroplast” some 3 billion years ago, which utilized a chemical called chlorophyll to capture energy from the sun and convert carbon dioxide and nitrogen into a range of chemical compounds and structural polymers by photosynthesis. These substances provide all the food required by the organisms not endowed with a chloroplast organelle in their cells.
This process also produced all of the oxygen in the atmosphere
The relative proportions of carbon dioxide and oxygen have varied very widely over the geological ages.
Oxygen_earths_atmosphere_historical
CO2_temperature_historical
It will be seen that there is no correlation whatsoever between carbon dioxide concentration and the temperature at the earth’s surface.
During the latter part of the Carboniferous, the Permian and the first half of the Triassic period, 250-320 million years ago, carbon dioxide concentration was half what it is today but the temperature was 10ºC higher than today . Oxygen in the atmosphere fluctuated from 15 to 35% during this period
From the Cretaceous to the Eocene 35 to 100 million years ago, a high temperature went with declining carbon dioxide.
The theory that carbon dioxide concentration is related to the temperature of the earth’s surface is therefore wrong.
Keep up the work to study what is really causing changes in the weather. Climate is the average pattern of thousands of weather events in one location.
What transit time between sinking and surge are we talking about.? 1 year 10 years 100 years ?
Radioactive carbon-isotope dating of the deep waters indicates that from the time of sinking into the deep until its return to the surface, a period of several hundred or even up to 1000 years will pass.
http://worldoceanreview.com/en/wor-1/climate-system/great-ocean-currents/
So that should mean that the energy pumped into the systeem many centuries ago (MWP) influences today’s climate.
Yes. This supports data that shows the age of stable deep water to be less than modeled age. The overturning system in models is very simplified with primary action at the poles. Thus models predict that it takes a long time for deep water to rise to the surface. However, when the actual age of deep water is measured, its age is quite a bit younger than the models predict, indicating that mixing is happening more frequently than was thought.
So take a look at the globe with the water removed. draw in what we know about the general placement and direction of the deep water currents. Notice all the mountain ridges? If these ridges stand in the way of a deep water current, mixing of old deep water could be happening there.
Desperate to plug yet another hole in the AGW dyke, the Warmists make a wild guess and call it a ‘plausible mechanism’.
800 foot tall subsurface waves that were not previously known to exist because there’s no physical representation whatsoever on the surface? Huh?
The researchers left instruments recording long-term measurements. The team will do another 40-day cruise in January to collect those instruments and map currents flowing through various gaps in the intricate channel.
So they will be going from the cold, wet, cloudy state of Washington in January to the warm climes of 8 south latitude. Not a bad gig if you can get it.
tty says:
September 11, 2013 at 3:50 am
WJohn says:
September 11, 2013 at 2:29 am
This raises the exciting prospect of submarine (adjective) submarine (noun) surfing.
If anybody knows anything about this it will be the world submarine (noun) operators, and they will tell you nothing.
Been there, done that. This technique was used by german U-boats transiting Gibraltar Sound in WW 2.
You beat me to it!
Here’s a good article on the u-boats and the Med., there’s an interesting piece near the end about a soviet submarine that was slipping in under a tanker when it got lifted up by one of those waves and hit the tanker. Had to surface, very embarrassing!
http://formontana.net/uboats.html
Surprise surprise! Fluid flow is turbulent. Hellooooo!
The massive pressure of water at the ocean floor forces it to adopt the temperature of lowest volume / highest density, i.e. close to zero. Its thermodynamically impossible for Trenberth to hide warm water at or near the ocean floor.