Researchers discover Icelandic current, change North Atlantic climate picture

Aug 21, 2011
Northern Denmark Strait showing newly discovered deep current, in relation to known pathway. Credit: WHOI

An international team of researchers, including physical oceanographers from the Woods Hole Oceanographic Institution (WHOI), has confirmed the presence of a deep-reaching ocean circulation system off Iceland that could significantly influence the ocean's response to climate change in previously unforeseen ways.

The current, called the North Icelandic Jet (NIJ), contributes to a key component of the Atlantic Meridional Overturning Circulation (AMOC), also known as the "great ocean conveyor belt," which is critically important for regulating Earth's climate. As part of the planet's reciprocal relationship between and climate, this conveyor belt transports warm surface water to where the water warms the air, then cools, sinks, and returns towards the equator as a deep flow.

Crucial to this warm-to-cold oceanographic choreography is the Denmark Strait Overflow Water (DSOW), the largest of the deep, overflow plumes that feed the lower limb of the conveyor belt and return the dense water south through gaps in the Greenland-Scotland Ridge.

For years it has been thought that the primary source of the Denmark Overflow is a current adjacent to Greenland known as the East Greenland Current. However, this view was recently called into question by two oceanographers from Iceland who discovered a deep current flowing southward along the continental slope of Iceland. They named the current the North Icelandic Jet and hypothesized that it formed a significant part of the overflow water.

Now, in a paper published in the Aug. 21 online issue of the journal Nature Geoscience, the team of researchers—including the two Icelanders who discovered it—has confirmed that the Icelandic Jet is not only a major contributor to the DSOW but "is the primary source of the densest overflow water."

"In our paper we present the first comprehensive measurements of the NIJ," said Robert S. Pickart of WHOI, one of the authors of the study. "Our data demonstrate that the NIJ indeed carries overflow water into Denmark Strait and is distinct from the East Greenland Current. We show that the NIJ constitutes approximately half of the total overflow transport and nearly all of the densest component.

The researchers used a numerical model to hypothesize where and how the NIJ is formed. "We've identified a new paradigm," he said. "We're hypothesizing a new, overturning loop" of warm water to cold.

The North Icelandic Jet in cross-section, adjacent to the continental slope of Iceland. Credit: WHOI

The results, Pickart says, have "important ramifications" for ocean circulation's impact on climate. Climate specialists have been concerned that the is slowing down due to a rise in global temperatures. They suggest that increasing amounts of fresh water from melting ice and other warming-related phenomena are making their way into the northern North Atlantic, where it could freeze, which would prevent the water from sinking and decrease the need for the loop to deliver as much warm water as it does now. Eventually, this could lead to a colder climate in the northern hemisphere.

While this scenario is far from certain, it is critical that researchers understand the overturning process, he said, to be able to make accurate predictions about the future of climate and circulation interaction. "If a large fraction of the overflow water comes from the NIJ, then we need to re-think how quickly the warm-to-cold conversion of the AMOC occurs, as well as how this process might be altered under a warming ," Pickart said.

"These results implicate local water mass transformation and exchange near Iceland as central contributors to the deep limb of the Atlantic Meridional Overturning Circulation, and raise new questions about how global ocean circulation will respond to future ," said Eric Itsweire, program director in the U.S. National Science Foundation (NSF)'s Division of Ocean Sciences, which funded the research.

The Research Council of Norway also funded the analysis of the data.

Pickart and a team of scientists from the U.S., Iceland, Norway, and the Netherlands are scheduled to embark on Aug. 22 on a cruise aboard the WHOI-operated R/V Knorr to collect new information on the overturning in the Iceland Sea.

"During our upcoming cruise on the Knorr we will, for the first time, deploy an array of year-long moorings across the entire Denmark Strait to quantify the NIJ and distinguish it from the East Greenland Current," Pickart said. "Then we will collect shipboard measurements in the Iceland Sea to the north of the mooring line to determine more precisely where and how the NIJ originates."

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Provided by Woods Hole Oceanographic Institution

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ryggesogn2
1.9 / 5 (9) Aug 21, 2011
Was this data in GCM?
Dug
3.1 / 5 (17) Aug 21, 2011
One more great example of how little we really know about even significant climate drivers like major ocean currents. Two weeks ago we learned that climate models were significantly underestimating the affects of aerosol shading, this week it's major heat exchange current. Yet, we are supposed to accept the projections of incomplete climate modeling as if it were 100% substantiated fact. It's a new science folks and we have a lot to learn and I suspect that both sides of the climate change argument are going to have more than enough crow to eat based on their current assertions.
NotParker
2.4 / 5 (14) Aug 21, 2011
"Settled damn it ... I said settled!"

-- Al Gore
Sanescience
2.2 / 5 (10) Aug 21, 2011
"critical that researchers understand the overturning process, he said, to be able to make accurate predictions about the future of climate and circulation interaction."

But we don't need accuracy, thinking is hard so we need consensus! We all need to agree what is the popular view and turn it into a media freight train so that we all can feel comfy with our moral righteousness and clarity of purpose.

In an age of grey, can't we just have this one black-white issue to "stick it" to those capitolists?
Pete1983
2.5 / 5 (8) Aug 21, 2011
It just occured to me while reading the article, and the above comments, that global warming isn't one of the "hard" issues, it's actually a relatively easy issue when compared to the significantly larger and harder problems our global society currently faces.

Is the reason climate change takes up so much "news" space because it's actually something we could as a society DO something about? I'm not talking about whether it's real or not or anything like that, I just mean, within the abilities of our society today, how much can we move collectively towards a different way of doing things? Seemingly not very much, since changing our energy systems seems to be about the limit, or just above the limit, of what we are currently capable of.

I would argue that we have significantly greater issues to deal with (our economic systems for example), yet since the level of change required is so high for these issues to be solved, we focus on the climate instead...

Silly meatbags.
LuckyExplorer
3 / 5 (6) Aug 22, 2011
"I would argue that we have significantly greater issues to deal with (our economic systems for example), ..."

A really short sighted argument!

Yes, we have to change some parts of our economic system, because there are rules - rjust rules - and automatisms lacking any realistic basis. Todays economy works and is managed in some ways based on dogmas not on truth and reality. - Infinite growth is an illusion.

But to negate the other great problems like the fast climate change would be wrong: It is very likely that the result of a climate change within such a short time as it is forcasted in combination with the growing (over-)population will lead to greater problems than the current economic problems. -
Other problems will be triggered to grow too.

The economic system is also a great issue, to disregard one for the other is the greatest mistake we could make!

We have to solve both!
MikPetter
3.7 / 5 (3) Aug 22, 2011
From the article above "While this scenario is far from certain, it is critical that researchers understand the overturning process, he said, to be able to make accurate predictions about the future of climate and circulation interaction. "If a large fraction of the overflow water comes from the NIJ, then we need to re-think how quickly the warm-to-cold conversion of the AMOC occurs, as well as how this process might be altered under a warming climate," Pickart said."
MikeyK
3.5 / 5 (8) Aug 22, 2011
See the anti-science Wattite sect have read Watts post and are using some comments from the bottom feeders verbatum. The deniers total lack of understanding of science and the gullibility with which they swallow the Watts bile is quite frightening.
antialias_physorg
3.4 / 5 (7) Aug 22, 2011
Is the reason climate change takes up so much "news"

If we don't address our climate problems then the economy doesn't matter - because we'll go extinct.

So yes: Environment first, economy a (very, very, very) distant second.

Vendicar_Decarian
4.2 / 5 (5) Aug 22, 2011
Typically the anti science denialists confuse theoretical refinement with an implied lack of consensus.

This is an understandable tactic given that their motivation is political, driven by fear and ignorance.

Fear is the primary organizing principle in America.
Sanescience
1 / 5 (2) Aug 22, 2011
Science is about building models that can make comprehensive specific predictions that can be tested against those physical systems that are being modeled.

We have some theories about how man's changing of the environment will effect the planet. Regardless of the merrits of those specific theories, lets all agree that sustainability is important and pollution and loss of species and habitat are problems. We have one space ship Earth and we need to manage it carefully.

The specific issue of AGW is a *risk* but treated in peoples minds differently, some people who are "faith based" point to trees and declare it a forest. They see it as obvious and don't understand why other people don't make the same leap of faith.

Fear has always been a, if not the, primary organizing force in society, fear is why AGW causes people to label other people as denialists.
ryggesogn2
1 / 5 (4) Aug 22, 2011
Economics and global climate are emergent systems.
Scientists are deterministically trained.
It's very easy for scientists to support socialism as the socialists claims they have 'the' formula.
The failure of 'the' formula is what motivated Popper to develop his falsifiability criterion for science.
Is it a coincidence that the 'solution' for AGW is more govt control of the world economy, a.k.a socialism?
Somewhere else on physorg some Vanderbilt engineers suggest humans do what humans have done for thousands of years with the climate, adapt. But what do engineers know?
Pete1983
5 / 5 (2) Aug 22, 2011
@ryggesogn2 - I'm sorry but thats an incredibly closed-minded view of scientists. "Deterministically trained"??? Are you suggesting that scientists simply follow the equations to wherever it takes them, with no consideration of reality? Yet you, with your lack of mathematical training can percieve reality more easily than they can?

Absolute poppycock.

Hell, take a look at some basic chemistry and the concepts of equilibrium. That's not "deterministic", it's equilibrium in a system damnit!

Also you're clearly thinking "communism" everytime you're writing "socialism", and you've clearly been indoctrinated into the American way of thinking, which is to STOP thinking, and just call everyone a commie.

Honestly, take a look at what you have written, it's just... wrong in so many ways.

Not that it's your fault though, you clearly typed that out pretty quickly, without review. I do the same sometimes and get things pretty damn muddled, so just apologise and we'll move on.
Pete1983
not rated yet Aug 22, 2011
"I would argue that we have significantly greater issues to deal with (our economic systems for example), ..."

A really short sighted argument!


How? I wasn't denying global warming or anything like that, which is what people SEEM to think I was doing for some reason. I was just using that as an example of what I guess you could call "social flexibility". I.e, how flexible we are as a society when it comes to resolving problems. I then went on to suggest that we aren't particularly flexible... I thought.

You said "A really short sighted argument!", and then went on to reiterate what I had already said it seems to me... Are we getting our wires crossed somewhere?
ryggesogn2
1 / 5 (4) Aug 22, 2011
Also you're clearly thinking "communism" everytime you're writing "socialism"

Socialism, communism, fascism, statism are equivalent. All support govt control, instead of protection, of private property, which includes not just land or 'stuff', but you, as an individual.
Are you suggesting that scientists simply follow the equations to wherever it takes them,

A computer model is based upon a deterministic equations.
And, yes, that is what I am observing with the AGWites.
Emergence is messy, is it not?
How many scientists are system thinkers?
http://www.system...ing.org/

you clearly typed that out pretty quickly, without review.

I have reviewed what I wrote many times and I have provided sources, many times.
ryggesogn2
1 / 5 (4) Aug 22, 2011
"The inherent strengths and weaknesses of computer models have crucial implications for
their application in foresight and policy analysis. Intelligent decision making requires the
appropriate use of many different models designed for specific purposesnot reliance on
a single, comprehensive model of the world. To repeat a dictum offered above, "Beware
the analyst who proposes to model an entire social or economic system rather than a
problem." It is simply not possible to build a single, integrated model of the world, into
which mathematical inputs can be inserted and out of which will flow a coherent and
useful understanding of world trends.
To be used responsibly, models must be subjected to debate."
http://www.system...tics.pdf
Of course NO debate can be permitted if it is a global climate model.
Pete1983
5 / 5 (2) Aug 23, 2011
@ryggesogn2 - Ok, so it seems like we're pretty much on the same page then in regard to scientific enquiry. I took your initial post to be stating that attempting to model basically anything was a waste of time, which judging by your recent comments, is certainly not what you were saying.

That being said, it seems your arguments against AGW are coming from a more free-market perspective than anything else. Are you so strongly pro-free-market that you would prefer to not do anything about AGW since it would result in a more socialistic system? I ask this as an aside to whether AGW is real or not, I'm more curious about your political views on this.

Personally AGW is a non-issue for me, as I'm quite strongly against free-market capitalism. I'm also strongly against the argument that this makes me a communist... Communism is not the opposite of capitalism, it's actually just as bad IMHO. I just want less pollution in the atmosphere, which would be a by-product of lowered CO2 emissions,
ryggesogn2
1 / 5 (4) Aug 23, 2011
I'm also strongly against the argument that this makes me a communist...

It's all the same in the end, govt control of your property.
you would prefer to not do anything about AGW since it would result in a more socialistic system?

Doesn't this depend upon who 'you' is and what 'you' can do about AGW?
The ONLY response of the political IPCC has been the socialist response, more govt control of the economy in an attempt to tweak a knob on a very uncertain global climate model.
I just want less pollution in the atmosphere, which would be a by-product of lowered CO2 emissions,

Then you support more nuclear power?
Pete1983
5 / 5 (2) Aug 23, 2011
Then you support more nuclear power?


Absolutely. I'm convinced that anyone against nuclear power simply don't understand it. Hell, 95% of the population don't have any understanding of radiation AT ALL.

Although really thats what we're fighting here isn't it? This whole thing would be a lot simpler if the public wasn't so unbelievably idiotic. Admittedly politicians are quite an issue as well, as so few have any scientific understanding at all.

We just need more scientific training for the broader community...
ryggesogn2
1 / 5 (4) Aug 23, 2011
We just need more scientific training for the broader community...

Why will that matter when there are scientifically trained people who vehemently oppose nuclear power?
http://www.ucsusa...wer.html
Pete1983
5 / 5 (2) Aug 23, 2011
We just need more scientific training for the broader community...

Why will that matter when there are scientifically trained people who vehemently oppose nuclear power?
http://www.ucsusa...wer.html


Umm... exactly? The article you linked to isn't stating that they are against nuclear power in the way the general public often is, they are simply advocating people actually think about what is involved with nuclear power.

In fact it seems they are mostly talking about how nuclear power isn't an AGW solution. That's pretty freaking obvious to anyone with a basic scientific understanding.

The average person is an idiot and really shouldn't have a voice in the conversation, but our failing democratic system allows it. Nuclear power is just another power generation option, nothing more. The problem is that it is under-utilised because the public don't even know what a half-life is.
ryggesogn2
1 / 5 (4) Aug 23, 2011
Pete, you asserted that if only those idiotic 'average persons' had a scientific education they would support nuclear power.

There ARE scientists who are just as idiotic as the 'average person'. How do you plan to indoctrinate the idiotic 'average person' to your POV?

I support and advocate for nuclear power, but I disagree with your assessment of the 'average person'.
Pete1983
5 / 5 (1) Aug 23, 2011
How do you plan to indoctrinate the idiotic 'average person' to your POV?

I've given up on that. It's just so much easier to prejudice somebody than it is to educate them. I'm waiting for societal collapse personally.

There ARE scientists who are just as idiotic as the 'average person'.

No doubt, but they have a significantly better grasp of reality, simply through an understanding of the scientific process.

Sorry, I'm not so much advocating solutions, as I am lamenting the horrible situation that it is the world today. There are so many established ways of thinking that have been shown to be conclusively incorrect, yet we continue using these methodologies regardless. A good example of this is the capitalist meme that people get paid an appropriate amount of money for their work, and that more pay means more/better work from the individual. This is only true in very menial jobs, yet we continue to assume it's true. It's all quite mad.
ryggesogn2
1 / 5 (4) Aug 23, 2011
A good example of this is the capitalist meme that people get paid an appropriate amount of money for their work,

So where is capitalist meme practiced today with all sorts of laws and union rules preventing this from happening?
Pete1983
not rated yet Aug 23, 2011
Well it's currently part of the current accepted world-view. It's practiced in every capitalist country in the world. The meme, in it's simplest form, is "more pay means more work from the individual". In a study commissioned by the US Federal Reserve, they found that more pay actually reduced the output of the individual when their work required them to think. In menial jobs, more pay, means more work from the individual. Yet most jobs today do require at least some thinking, and strangely more pay results in less work.

Yet we still continue to pay Executives insane pay-packets, and as a society we allow it because of this idea that they have earned it.

I'm not sure what you mean in relation to laws and union rules though, this is more of a cultural thing I guess.
GSwift7
3 / 5 (2) Aug 24, 2011
We just need more scientific training for the broader community...


Every poll and study I've seen seems to indicate that education isn't a strongly deterministic factor in regard to how people view the topic of climate change and mitigation. It's almost a perfect political split, with conservatives and liberals on opposite sides and moderates split evenly down the middle.

I mentioned this on another thread, but this crowd seems like it will enjoy fighting over this bone: It's commonly known that aforestation is occurring in Eastern USA. Forests are expanding faster than we're cutting them down. Unfortunately, it's causing grassland species (like certain birds) into sharp decline and possibly even regional extinctions. Forests causing extinctions. Ironic. Fortunately, that's countered by other species who benefit. It's always a battle in nature.
GSwift7
3 / 5 (2) Aug 24, 2011
back on topic though:

As for melting fresh water ice causing a change in the conveyor system, there have been studies of sediment cores in both the atlantic and pacific about that. The sediment cores seem to indicate that even at the end of the previous glacial period, when massive amounts of fresh water flowed off the continents, the ocean conveyors remained basically as we see them now. They appear to be robust, based on sediment cores. The conveyors seems to have survived throughout the previous glacial, as well as the interglacial before that. That's pretty hard evidence to ignore, so I'm not sure what the guy above is talking about when he says that he's afraid of the conveyors breaking down. The ENSO cycle also seems to have been unaffected in general, just fyi.
ryggesogn2
1 / 5 (4) Aug 24, 2011
In a study commissioned by the US Federal Reserve, they found that more pay actually reduced the output of the individual when their work required them to think.

What output was measured, power point slides?
GSwift7
3 / 5 (2) Aug 24, 2011
In a study commissioned by the US Federal Reserve, they found that more pay actually reduced the output of the individual when their work required them to think.

What output was measured, power point slides?


Well, it's not a scientific study, but where I work, I noticed that the amount of meetings we've been having seems to be increasing and causing a serious decline in the ability of our managers to get tasks done. So, I stopped what I normally do and began graphing our meetings versus the work everyone else was supposed to be doing and the work they actually got done. I presented my results to the boss, who immediately scheduled a meeting to discuss this with the other managers. The group decided that it would be best to start with a week long team building exercise at a resort, followed by weekly meetings to keep track of how much time we spend on meetings. I'm an efficiency expert, but I never promised to use my powers for good. ;)
Pete1983
5 / 5 (2) Aug 24, 2011
In a study commissioned by the US Federal Reserve, they found that more pay actually reduced the output of the individual when their work required them to think.

What output was measured, power point slides?

Well now your just trolling and you know it.
antialias_physorg
5 / 5 (1) Aug 25, 2011
In a study commissioned by the US Federal Reserve, they found that more pay actually reduced the output of the individual when their work required them to think.

I can attest to that. Think about it: if you are getting paid to do what you dearly love doing anyway then the amount of pay (beyond a very modest level) doesn't matter at all.
Pete1983
5 / 5 (1) Aug 25, 2011
In a study commissioned by the US Federal Reserve, they found that more pay actually reduced the output of the individual when their work required them to think.

I can attest to that. Think about it: if you are getting paid to do what you dearly love doing anyway then the amount of pay (beyond a very modest level) doesn't matter at all.


Absolutely! It all comes down to the idea that the reason anyone works is because they get paid for it! Of course for most of us, that is actually true, but to say that without pay we would all just sit around starting at the clouds?

Absurd surely?
Modernmystic
1 / 5 (2) Aug 25, 2011
For the sake of argument...even if true what's the worst the "settled science" people predict? 2-3 degrees in the next century? IF true during the PETM temps were higher by 12 degrees and there was no evvviiiill catastrophe that befell the "fragile" biosphere...that IS settled science.

Not worth the trillions of dollars of damage that cap and trade and other idiotic schemes will do to the economy and yet not even impact climate change anyway.

If you REALLY want to cool off the planet make a regulation to paint all rooftops and car hoods and roofs white. That one thing will do more than all the fascist crap masquerading as a solution to the problem being shilled right now...

ryggesogn2
1 / 5 (3) Aug 25, 2011
In a study commissioned by the US Federal Reserve, they found that more pay actually reduced the output of the individual when their work required them to think.

What output was measured, power point slides?

Well now your just trolling and you know it.

I want you to back up your claims.
Pete1983
5 / 5 (1) Aug 25, 2011
In a study commissioned by the US Federal Reserve, they found that more pay actually reduced the output of the individual when their work required them to think.

What output was measured, power point slides?

Well now your just trolling and you know it.

I want you to back up your claims.


If you did you wouldn't be asking what output was measured, and then stating "powerpoint slides". If you wanted me to back up my claims you would be asking for a link to the study.
ryggesogn2
1 / 5 (3) Aug 25, 2011
What output was measured? Feel better?
Pete1983
not rated yet Aug 25, 2011
This video is pretty good for info on the subject:
http://www.youtub...embedded
ryggesogn2
1 / 5 (3) Aug 25, 2011
The most common 'output' to convey ideas, the work product of thinking, IS a power point presentation.
Of course other measures can be requirements documents, drawings, analysis reports, lines of code, ...

A federal reserves study is on youtube? I am old school, I still read.
Pete1983
5 / 5 (1) Aug 25, 2011
I prefer to read too, however I can't find the specific study, so for the meantime the video will have to do. It's a good introduction to the concepts none the less.

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