An alarming claim from from the University of Exeter, based entirely on modeling.
Study finds early warning signals of abrupt climate change
A new study by researchers at the University of Exeter has found early warning signals of a reorganisation of the Atlantic oceans’ circulation which could have a profound impact on the global climate system.
The research, published today in the journal Nature Communications, used a simulation from a highly complex model to analyse the Atlantic Meridional Overturning Circulation (AMOC), an important component of the Earth’s climate system.
It showed that early warning signals are present up to 250 years before it collapses, suggesting that scientists could monitor the real world overturning circulation for the same signals.
The AMOC is like a conveyor belt in the ocean, driven by the salinity and temperature of the water. The system transports heat energy from the tropics and Southern Hemisphere to the North Atlantic, where it is transferred to the atmosphere.
Experiments suggest that if the AMOC is ‘switched off’ by extra freshwater entering the North Atlantic, surface air temperature in the North Atlantic region would cool by around 1-3°C, with enhanced cooling of up to 8°C in the worst affected regions.
The collapse would also encourage drought in the Sahel – the area just south of the Sahara desert – and dynamic changes in sea level of up to 80cm along the coasts of Europe and North America.
“We found that natural fluctuations in the circulation were getting longer-lived as the collapse was approached, a phenomenon known as critical slowing down,” said lead author Chris Boulton.
“We don’t know how close we are to a collapse of the circulation, but a real world early warning could help us prevent it, or at least prepare for the consequences” adds co-author Professor Tim Lenton.
The study is the most realistic simulation of the climate system in which this type of early warning signal has been tested.
“The best early warning signals in the model world are in places where major efforts are going into monitoring the circulation in the real world – so these efforts could have unexpected added value’ adds Professor Lenton.
###
‘Early warning signals of Atlantic Meridional Overturning Circulation collapse in a fully coupled climate model’ by Chris Boulton, Lesley Allison and Timothy Lenton is published today in the journal Nature Communications.
“Experiments suggest that if the AMOC is ‘switched off’ by extra freshwater entering the North Atlantic, surface air temperature in the North Atlantic region would cool by around 1-3°C, with enhanced cooling of up to 8°C in the worst affected regions.”
By George, are they finally catching on to the real danger, cooling, instead of warming?
Everybody know climate is not chaotic, so no such surprises are possible in the settled science.
Yeah, climate is not weather. Or a double pendulum. Or any other complex non-linear system. /sarc
Experiments? What experiments?
This is modeling run AMOK.
Don’t get you knickers in a twist. This one is a “highly complex” model.
Same apocalyptic scenario – different al – gore – ithm.
But they do say that persistence is directly related to success. Have another try.
“Experiments suggest …”
Computer games ARE NOT experiments.
End of.
This stuff would be funny if it wasn’t the equivalent of falsely yelling fire in a crowded theater.
I was thinking these are the type who would have pulled the fire alarm in school just to watch the reaction.
(Conclusion based on a psychological model, of course.)
Stephen Schneider would have been proud of them!!
BTW Anthony, why all if the secrecy about who is involved in your “Open Climatic Society” venture? The claims made about the organisation’s objectives and the lack of transparency remind me too much of out-of-work high-school art teacher John O’Sullivan’s “Principia Scientific International” blog for my liking. “Wattsupwithtransparencywatts”
Best regards, Pete
“Experiments suggest that if the AMOC is ‘switched off’ by extra freshwater entering the North Atlantic, surface air temperature in the North Atlantic region would cool by around 1-3°C, with enhanced cooling of up to 8°C in the worst affected regions.”
I’m assuming “extra freshwater” is melt water, but wouldn’t the cooling tend to counteract that?
Partly, Paul.
But more likely extra rain
More Faux science:
‘experiments suggest …..’
Dickering with models does NOT constitute an experiment.
‘a phenomenon known as critical slowing down’
Wow, that does sound frightening – job done.
“Dickering with models does NOT constitute an experiment.”
Sure it does.
Suppose I want to understand the effect of a large asteroid hitting the earth off the coast of NYC.
I might be able to learn some things from history, but to gain a deeper understanding, I build a model.
I run experiments with the model. I get results that show what kind of wave height I might see with increasing sizes of asteroids.
The models suggest that for a certain size of asteroid, building a wall to protect the city is futile.
The model is never tested against real world data. It’s derived form physics as best we can. It probably misses a lot of detail. But I dont need to know the exact wave heights, I just need something that is
in the ball park.
I want to know if a crew protection system will work to protect astronauts if their rocket blows up.
Hmm. I dont build a rocket , put people in it, and then blow it up to see if my design works.
I build the the best model I can. A lot of detail gets simplified and parameterized.
Many designs fail in simulation. When a design fails in simulation, we usually dont argue that the simulation is flawed and the design might work, so throw Johnny in the cockpit to see for sure.
Models are used to conduct experiments where you cannot afford to do a real experiment. Or where the
experiment is too big to fit in the lab.
Its best if I can validate my model against reality. But sometimes that is hard or impossible.
Example: In building the F/A-18 there was a requirement that the plane be able to survive hits from
Air to Air gunfire without a catostrophic fire. basically, you needed to take hits to the fuel tanks and survive
say 95% of the time.
How do you test that?
Simple: you run a model.
https://www.dsiac.org/resources/models/covart
How good is COVART? That’s hard to say. I once worked on a proposal to destroy 50 million dollars worth of airplanes to validate one small part of the model.
Bottom line, we use models all the time to run experiments. They are called simulations.
Nobody mistakes these experiments for experiments with the real world.
In short, IF you are ignorant of how a field uses a term (‘experiment or simulation) then you wont understand what they write.
“In short, IF you are ignorant of how a field uses a term (‘experiment or simulation) then you wont understand what they write.”
And in the field of climate science do a) those writing the papers actually know/care about the difference and b) do those reporting on it also know?
Then there is the FACT that most people seem to take the simple view…experiment is something done with physical instruments on ‘real’ items/conditions and simulations are done with computers.
Example: In building the F/A-18 there was a requirement that the plane be able to survive hits from
Air to Air gunfire without a catostrophic fire. basically, you needed to take hits to the fuel tanks and survive
say 95% of the time.
How do you test that?
Simple: you run a model.
================================================
Yes
But if a global warming scientist were running this model,. they would add hits on the f-18 by photon torpedoes and phaser fire.
That’s about the same fantasy that current global warming models being run with “An Increase in C02 will destroy the planet.”
Yes, many models work well
Global warming ones don’t
I wonder why Mosher did not use climate models as his examples?
Is it right that governments formulate policy on the back of models that have a poor track record (ask the IPCC).
What do you think of these models Mosher?
As fuel tanks and pilots have been vulnerable since the first air combat in 1914 (1917 for some) there is 100 years of real unadjusted data on building combat aircraft. It does mean you get a decent model, combined with the fear of a huge damages and no more lucrative contracts for screwing up then one imagines the models would be pretty good. I bet a couple of fuel tanks were built and shot at. Could test fuel tank busting bullets and fire extinguishers at the same time.
Mosher
In the examples you note the variables and their interactions are fairly well known. In climate ( or the “AMOC system”), not so much.
Then call them what they are then – simulations.
The use of the word experiment is Press Release spin to add credibility to a typically speculative piece of climate ‘science’. The writers know very well what the normal understanding of this word is.
If you want to know if astronauts can survive an explosion, yes you model, but you don’t put humans in the capsule until you build a couple of them and blow them up. With sensors inside to measure the intensity of the forces.
If you want to know what happens to an airplanes fuel tank when it is hit by anti-aircraft fire, you build one and then you explode an anti-aircraft shell nearby and measure the results.
Your ideas regarding how models are used in the real world are quaint to say the least.
The French refer to experiments (old French) as experiences. Both from the Latin ‘experimentum’ for trial. If models are used to see what will happen IF something changes, then you can refer to them as experiments but I think that it is still misleading because it is like changing a variable in a simple function. You wouldn’t refer to that as an experiment. Is a plot of a sin function an experiment?
When they are used in place of chicken entrails it is wrong to refer to them as experiments as they have not been tested by comparison with the real world.
I’ll use an example from my own field where I tried to understand a complex chemical process using the knowledge derived from models and backed up by experiment.
I found that if you purified the starting material more thoroughly that you got completely different results than what was predicted by the models developed over decades. I got called a fraud for my troubles. The models are still state of the art.
What you describe, Mosh, is not “dickering” with models. It’s dicking with models. And it’s not an experiment, even if the model is perfect, which no climate model has ever been. Calling it an experiment is just another dangerous way for climate scientists to fool themselves.
Oh yes they do.
But some people wilfully use the term to deceive those (possibly a majority of the population) who are not aware of the distinction.
Mosh is right!
But then again only if the model you are working with actually works before you start playing
Before you can use model to perform simulation (not experiment) that you can trust you have to validate it. Unvalidated models are garbage, no matter what.
Only climate scientists use term “experiment” to describe model runs. Everywhere else we call it simulations.
I don’t know how F/A-18 was designed, but I can’t believe that it was “tested” using models with predictive capabilities of current climate models. Somehow I suspect that it was really shot at by real bullets on scale models and on real things, in the air and on the ground, during many different design phases.
If an engineer ran 50 model test runs, and they all performed poorly, say they dramatically overestimated the altitude a plane could fly, and then the engineer recommended that said plane could fly over any mountain at the model mean of his 50 model run, he career would be short lived, to say the least.
I affect this is exactly what the IPCC does.
Actually, Mr Mosher, we took F/A-18 fuselages out into the desert and fired lots of rounds into them. It’s called live-fire testing and is required for new DoD aircraft (although the requirement is often waived). COVART is good, but life-fire testing proves the design objectively. (The engineers involved in ballistic survivability reported to me.)
Models are good, GIGO is bad. Some models are better than others and unfortunately climate models don’t fall into the good category. We’ve had decades to see how the climate models have performed and it isn’t pretty.
When and if a good climate model is constructed, it will be decades before the results can be confirmed with observations. Until that time arrives all climate models will be looked at with disdain and rightfully so.
If they had built a proper model or readily admitted otherwise when it became apparent they were failing, I don’t believe they would in the same position today. Sometimes it seems CAGW alarmist live in Sim City.
“Example: In building the F/A-18 there was a requirement that the plane be able to survive hits from
Air to Air gunfire without a catostrophic fire. basically, you needed to take hits to the fuel tanks and survive
say 95% of the time.
How do you test that?
Simple: you run a model”
###
Wrong. You fire A to A artillery at it. That’s what Test Engineering is all about. Only a leftist idiot would trust a model for this. You ought to do a bit of research before spouting off and making a fool of yourself.
Mosher is the perfect example of why English majors should not be discussing computer science topics,
Space Shuttle Challenger Accident:
http://history.msfc.nasa.gov/book/chptnine.pdf
Boeing 787 Dreamliner Wing Failures:
http://www.designnews.com/document.asp?doc_id=228554
More bullshit from Mosher. Looks like this was live fire tested,
http://www.airspacemag.com/military-aviation/shoot-em-up-35669028/?all&no-ist
Maybe next time you should do some research before posting more bullshit.
Mosher, most of what you say makes sense, but it is still NOT an experiment. It is a simulation. Simulation is NOT an experiment. It doesn’t mean it is useless. It is useful in many cases when experimentation would be extremely costly and the simulator has already proven many times that it closely simulates reality, and therefore experimentation is considered unnecesary. Now tell me who and when testeed the simulator that has been used in this piece of science, I mean, crap.
None of the people that run simulated bullet impacts on F-18 fuel tanks dared to say that they had verified the resistance experimentally. No. Wrong. Simulation does NOT constitute experimentation, Doing simulation instead of experimentation does not allow you to call the simulation an “experimentation”. Curiosity’s landing on Mars was simulated hundreths of times before it actually went to Mars and landed. None of those simulations constitued experimentation, The only experimentation was the actual landing on Mars.
Steven – that’s a calculation, not an experiment.
“Sure it does.”
No it doesn’t.
Stop making stuff up.
If you don’t do a real experiment, do what Einstein did, call it a “Thought experiment”. Running a computer simulation is the same as a theory. It is the embodiment of a theory, put together through the algorithm it runs.
After you have developed your theory, run your simulation, etc, you still need to know if it is real, or just castles in the air. You need to make a prediction and run an experiment (a real experiment) to verify the theory predicted the experimental result. And when the experimental result is different from the theory (model), you don’t blame the experiment, you acknowledge that the theory was wrong and go back to the drawing board. Yes you guys at the University of East Anglia, I am looking at you.
We’ve heard this nonsense before. They do like to recycle their nonsense, so I guess that’s “green” of them.
Could… could… if… would… could… could… Now give those of us who have reached the status of elite complete control of energy so we can protect our families and you can twist in the hot (or cold) wind of climate change.
By all means, we want to avoid this:
Not to worry, paleoclimatologist Dennis Quaid will save as many as he can.
I think his brother Randy Quaid would make a far better climate “scientist.”
I suppose the fresh water pulse would come from where??
Greenland’s ice sheet continuously drains to the sea as it slowly melts into the north Atlantic. Even if it accelerates it’s melting in coming centuries, the fresh water is not pooling in a Lake Agassiz-meltwater lake where it can release as one big freshwater pulse.
From their Results:
From their Discussion:
Consider those two statements. 1 Sverdrup is approx equal to all the annual current annual global freshwater input into the world’s ocean. To get AMOC collapse, they had to steadily increase freshwater input between 20N- 50N at 0.05 Sv/century. Then at the 8 century point, at an additional 0.4 Sverdrup input/century to this part of the N.Atlantic, AMOC collapsed.
Where does this steadily increasing amount of fresh water come from? Not from North America or Europe or Siberia. In early Holocene, the St Lawrence Seaway and the Mississippi River supplied much of the fresh water pulse to the North Atlantic from the melted Laurentian Ice Shield of the LGM. Greenland is north of the 50N point. The dynamics of a southern Greenland ice sheet melt would be completely different, probably taking many thousands of years even in a warming planet to get to those Sv input levels. In short it would not be anything like these modeled inputs or system responses.
This analysis from U Exeter is a fantastical-unrealistic modeling of an input to an AMOC-like system that does not currently exist on 21st Century Planet Earth nor will it again until another Ice Age termination.
Reading their results, they could only get AMOC collapse when they used steadily increasing Sv inputs to keep driving the system away from equilibrium. When they used constant (not increasing) Sv inputs, they could not get AMOC collapse below 0.25 Sv at any time span. Constant Sv inputs above 0.25 Sv/century did lead to collapse, but they didn’t get their cherished “early warning signals.”
Quoting them,
A Joel, it’s inevitable. Here is a thought experiment for you. In two years, President Obama will be back in Chicago. He’ll be walking along the edge of Lake Michigan one day in downtown Chicago, when a gasoline powered car backfires sending a plume of Global Warming into the air, the President is startled and falls into Lake Michigan along with his huge ego. This sends a huge tidal wave north into lake Superior and Huron, setting up a harmonic wave that empties the whole of the Great Lakes into the St. Lawrence River and on out into the Atlantic Ocean, halting the Atlantic Conveyor and initiating a new Ice Age. The crazy squirrel finds all kinds of acorns embedded in the ice, pulls one out and the whole Atlantic drains into the Pacific creating snowball earth.
There, see what models can do. We just demonstrated that Global Warming caused Ice Ages and Snowball Earth. Now we just have to wait two years to verify the model. 😉
(cleaning up the beer from my monitor.) Thanks Wayne for that mental image.
I just hope that tidal wave will wash back over Chicago and then thru Springfield, so that the good people of Illinois could clean out the rats.
Obviously important.
Needs more funds.
Fling funds, no accounting of their use needed.
games engineers understand models (and how to force simulation of wanted behaviors) much better than these idiots!
Are these climate “modellers” really unemployed Games Engineers.
Not only pretend Nobel Laureates, incompetent scientists but also failed Games Engineers – such is climate “science”.
Computer model experiments!
So now it’s gone from “we only have a few years left to act” to “early warning signals are present up to 250 years before it collapses”? So when absolutely nothing happens (like for maybe 18 years or so) they are trying to tell us to give them another 250 years to carry on with the same old fear mongering?
The title of the paper is amusing.
And here is their next grant application right in the abstract itself.
So they try to alarm. Then they demand more money based on the alarm. This whole exercise is complete and utter bollocks.
‘Early warning signals of Atlantic Meridional Overturning Circulation collapse in a fully coupled climate model’ by Chris Boulton, Lesley Allison and Timothy Lenton is published today in the journal Nature Communications.
OK. They found something in the model.
1. Just how good is this model?
b) How many years of observations will it take to verify that what they found in the model actually occurs?
3. If we had the early warning, is there anything that could be done to prevent the collapse of the circulation?
iv) Will Boulten, Allison, and Lenton be retired before we know the answers to questions 1-3?
“How good is this model”?
Guess we won’t know for 250 years.
Now THAT is what I call a very long trough indeed…oink, oink oink.
If they got this idea from the Younger Dryas they are on shakey ground. That period preceded a postglacial warmup with, I believe, a false low temperature signal from O18 depleted meltwater. Lots of meltwater means high inland temperatures, not low.
That is back to the New Ice Age propaganda of the 70th. Does it mean, Club of Rome and Global 2000 were eventually right, after all?
OK, this has happened before. Why the panic?
Wake me up when the early warning alarm bells go off, and then I can go back to sleep for another 250 years.
More natural variation wrongly interpreted as “signs of impending doom”.
Why don’t they just read the signs from entrails like the soothsayers of old. It would have as much credibility, it would cost a lot less and at least there’d be a lamb supper afterwards.
…ya know… I had a leak in my roof this past monsoon season… it worried me, because another rain storm could have made it much worse. The insurance claims adjuster came by last month and asssured me that the rainy season was over, but it would be a good idea to get the roof repaired during this upcoming “dry period” in Vegas.
So, for the past weeks, I have been watching the NOAA weather, the local broadcasters, and the weather- underground for upcoming weather. …Biting my nails, hoping for no new rain to further damage my roof and ceiling. NONE of the forecasters agreed on showers that were coming here (or not) from the storms that hit California last week.
Well, the NOAA, and its super computers got the forecast WRONG (again and again) all week, last week. Every single daily forecast was wrong regarding temperature and rain. A 20% chance of rain turned out to be a 100% chance according to the local forecaster. The weather underground folks were not correct either.
So how the H#LL can some MODEL figure out stuff decades from now? … if the super computers can’t even be as good as the local forecasters looking out the window?
I am an engineer. I have worked with many so-called “model” scientists. The bottom line is that thousands of variables fed into the model, in the wrong way, or with the wrong coefficients (weighting), and other factors can change everything about the model output. In college, I had a hard time solving equations with 2 or three unknown variables…I can’t imagine how to handle thousands.
The summary of super computers and models: Garbage In = Garbage out.
By the way… my roof leaked again…because I believed the NOAA.
I’d go with the Farmer’s Almanac first.
OK here is the full paper. Governments must act now based on the following.
Thank you Jimbo for providing us with a link to the full paper. Very interesting , with many enticing references but densely argued and I suspect that even the acknowledged experts on this site will need some time to assess its relevance. Unfortunately whilst readers elsewhere may examine and digest this over a course of weeks whilst working on comments or collaboration , on a blog site like this the topic will have effectively passed away within a week.
Incidentally , if anyone else is wondering what exactly we should be monitoring , it is the Sverdrup (Sv), a measure of ocean current flow equal to 10^6 m^3/sec (acknowledgements to Wiki).
“Experiments suggest”????? Since when is modelling, experiments?
“The study is the most realistic simulation of the climate system in which this type of early warning signal has been tested.” So they’d like us all to believe!
And it’s probably true, but only because they are comparing it with even greater pieces of shit!
“We found that natural fluctuations in the circulation were getting longer-lived as the collapse was approached, a phenomenon known as critical slowing down,” said lead author Chris Boulton.”
Perhaps they would be better to study a phenomenon known as critical thinking. http://www.early-warning-signals.org/theory/why-should-we-expect-early-warning/
Did anyone let these grubers know that arctic ice is at or near the 30 year mean?
Modeling modeled models once again …….
Well doesn’t this and some other authors predict that global warming will cool Arctic and bring cold winters to e.g. the Great Britain? So more sea ice proves CAGW. And less sea ice does that as well.
Hot is cold and cold is hot. More is less and less is more and if anything happens, it can be blamed on Co2. Now if the dog craps on the neighbors yard, that can be blamed on CACA.
Capital G, as in “Grubers”.
As in the “grubers” continue their lies.
When scientists say that “experiments suggest,” we normally assume that means observations on carefully controlled phenomena in the real world. Obviously that is hard to do with planetary-scale ocean currents. So these ‘climate scientists’ play with computer models instead. But to imply that they are conducting actual experiments in the natural, not virtual, world is seriously misleading, if not actually fraudulent.
/Mr Lynn
Please no, not the AMOC collapse, please anything but that. There is slight hope, maybe Bruce Willis can nuke the AMOC like he did the meteor in the movie Armageddon (1998).
On a serious note, modern Homo Sapiens have been dealing with any and all climates for at least 100,00 years and surprisingly for some they did it without an iPhone. Many modern races do well in the ice and others seem to get by in the tropics. We can survive weather. Why this constant fear mongering about climate, why this little faith in the human race to deal with weather. Why this bizarre need to have to change the weather.
We are now going to control how ocean currents work and evolve? Really?
Is it really just the fear of change? Yes the climate will change, no amount of caterwauling is gonna stop the climate from changing. So get your boots on and deal with it when it comes, not cry about some unpredictable event that may or may not happen centuries from now.
“[…] modern Homo Sapiens have been dealing with any and all climates for at least 100,00 years and surprisingly for some they did it without an iPhone. […]”
Nooooo!!! Say it ain’t so, Alx!
I’m counting on humanity to tweet its way out of the next glaciation while they follow their iPhone GPS to safety. (If only Moses had an iPhone…)
>>“We don’t know how close we are to a collapse of the circulation, but a real world early warning could help us prevent it, or at least prepare for the consequences” adds co-author Professor Tim Lenton.<<
Prepare why and for what, if it is unsure that/if something is going to happen?
It needs no academic background to see that mankind has always adapted to the environment: Human beings everywhere: from Siberia's -50° C or more(well, more is less in this case) or to the Sahara's +50C. Don't worry, mankind will exist when the IPCC and the public fund addicts have become reminders of ghastly times long gone by…
And in very much associated news…
https://uk.news.yahoo.com/growing-antarctic-ice-sheets-may-sparked-ice-age-133750917.html
“They looked at a different part of the world than is traditionally looked at for the onset of cooling,”
Because you don’t normally look for cooling anywhere near the place with all the ice? (I think the good Doctors comment was truncated.)
This is an interesting article looking at the glaciation at the start of the Pleistocene glacial epoch. They found that it coincided with warming of deep Pacific water (yes – warming not cooling). This is because warmer Atlantic water that normally would go south and melt Antarctic ice, instead was diverted into the deep Pacific. This allowed Antarctic ice to grow, and this was the fore-runner to global glaciation.
Note that there is an element of “zero sum game” to this. For glaciation to begin it is not necessary for there to be any change to the global heat budget. Just some deep ocean rearrangement of heat is all that is needed.
What might make this nice piece of palaeo-oceanography quite relevant to the current interglacial are the following two recent observed trends:
1. Antarctic sea ice is growing
2. Deep ocean OHC is apparently growing fastest in the southern ocean.
Even if we enter truly a new ice age, with 500 meters of glacial material burying Al Gore’s house, there will be scientists and models demonstrating it is a derivative of global warming. There is no winning this one .
Of course if the AMOC is switched off in the absence of “extra fresh water”………
The solution to the problem is to de-fund their work.
Chris Boulton, Lesley Allison and Timothy Lenton Some new names to keep an eye out for in the CAGWosphere
Keywords:- simulation, model, may, up to, suggesting, scientists
“complex model to analyse the Atlantic Meridional Overturning Circulation”
Because they can’t use the ACTUAL AMOC to analyse the AMOC???
A little off topic but I have just finished watching the movie Judgment at Nuremberg. I have seen it a few times before. I highly recommend that everyone interested in global warming watch it. It covers the reasons why men ( judges of high standing in Germany in the mid thirties to the mid forties) became accomplices in the crimes against humanity.
Here is a youtube link to a six min segment. http://youtu.be/N3BwK51YFgQ
I’m not clear on the meaning of the phrase ‘fully coupled climate model’.
Does this mean that the model has a good sex life?
Global warming causes catastrophic cooling.
Notice that this is NOT a negative feedback mechanism. There is no minor cooling that stops the other cooling that if left unattended would be a global heatwave. This is one disaster sparing us from the opposite disaster.
The assumption here is that the Earth’s climate is always on a critical tipping point. The physics is delicately balanced and works as a series of interconnected on-off switches. There is no natural balancing going on.
The principle of Gaia is that the world operates in a way to minimize major disruptions to the habitability of the planet. The referenced work is based on a refutation of this principle: the world has a series of switches, at present fortuitously set to provide a positive environment for living organisms, but which are systemically capable of flipping into a life-endangering way. This goes counter to the history of our planet, ice-ages not withstanding (as there was no great extinction during the ice-ages, large mammals excluding AT THE END OF THE LAST ONE).
Hollywood is writing the IPCC script. There is no profit in life-as-usual. A virus contained in a village is no good, it has to threaten the existence of mankind to get to the big screen.
Wake me up when their prediction comes to pass. Excuse me; that’s projection.
Modelling of ocean circulation is more successful than of the atmosphere. The latter is mostly defeated by chaos. But ocean currents while still influenced by nonlinear dynamics are slower and more constrained. Phenomena such as the bipolar seesaw and the Younger Dryas and run up to the Holocene inception.
Like all human activity modelling fails when it becomes arrogant and over ambitious. Take the current topic for instance – the AMOC. At the heart of the AMOC is a positive feedback linked to salinity which gives the AMOC a fundamental instability. Basically, the gulf stream carries Carribean warm water with elevated salinity across the Atlantic northwards. Once near the Arctic this highly saline water cools to become super-dense, so much so that it sinks all the way to the ocean floor and flows south, forming the North Atlantic bottom water. This cold downwelling further drives the gulf stream via the AMOC.
This positive feedback has an important implication for the AMOC – it becomes an “excitable medium” in chaos terms. This means it is subject to suddenly switching on and off. Discussions of the AMOC such ad the one above that look for a discreet cause of each switching on or off – such as a salinity pulse – miss the point that the system is subject to such switching due to nonlinear instability.
Now a sensible goal of modelling here would be to simulate the AMOC instability that is well known, being the cause for instance of the Younger Dryas. And to tie such modelling as close as possible to palaeo data.
But to go further than this to attempt an all-singing all-dancing simulation of the whole system – that is too inductive and much less safe.
But if it can get a decadal long grant for an AMOC monitoring system from a naive grant-funding committee (or not so naive if they are CAGW believers of catastrophe alarmisms and part of the fraud) … So at this point…what difference does reality make? We are talking about a tenured career’s worth of gub-ment funding for a university!!!
Early warning signal, reminds me of the story of the ‘Channel Trumpet Blower’. Seems the English were worried about an invasion from the short Frenchman Napoleon. Set up an early warning, with some watching the English Channel who would blow a horn when he saw Napoleon’s troops crossing the water there. They then forgot the mission & position and kept it up until the start of WW I. (for those historically challenged – Napoleon died in 1821 and WW I started 1914) Talk about paying for useless warning is nothing new.
Saw paragraph 2 “… used a simulation from a highly complex model…” and stopped reading.
GIGO
More models of doom.
Another good example of:
Special
Climate
High
Intensity
Terrorism
Better know as SCHIT.
It’s worse than we thought, and you’d better send lots of money so we can save you.
Stop paying these idiots!
They used a highly complex computer model. Translation: They put seagull entrails in a blender, poured them on to a hockey stick and a drunk U.N. bureaucrat read it and sounded the alarm.
Borrowed this link from another thread. I repeat: “One takes a look at the vortex’s and flows and one just has to realize that if there is ANYONE who believes they can model and predict based on the number of variables present is this amazing world of ours is either an idiot, has an ego that will not quit or really needs the money and is willing to sell their soul to sell ice to Eskimos.”
http://earth.nullschool.net/
‘The study is the most realistic simulation of the climate system in which this type of early warning signal has been tested.’
But is still like expecting that given enough time 100 monkeys can write Hamlet
models all the way from those with much to lose and nothing to gain should ‘the cause ‘ fall
“We don’t know how close we are to a collapse of the circulation, but a real world early warning could help us prevent it, or at least prepare for the consequences” adds co-author Professor Tim Lenton.
So, how exactly are they going to prevent it?
Draining the oceans maybe? Or damming the rivers? How about stopping the rain?
No, the best bet would be turning off the sun. That should work a treat. Let’s do that.
Our taxes are paying for these idiots?
The study is the most realistic simulation of the climate system in which this type of early warning signal has been tested.
Uh-huh. And that’s supposed to be validation? How many instances of the AMOC switching off did they use to train their models? Aren’t they simply saying they got the models to match the pattern used to train the models. Hardly realistic. Just as unrealistic as expecting all other factors to remain the same over 250 years.
The Youger Dryas is an example of the AMOC switching off and on. It has been modeled reasonably successfully.
Is the “pauze” part of a “critical slowing down”?
“Mosher”, in Esperanto, means ‘move on to the next posting’.
This is just the plot from “The Day After Tomorrow” (2004) isn’t it?
By Jove! A massive negative feedback! So if Greenland ever started to melt it would flip a switch in the ocean current system and freeze itself up again. No need to worry about Greenland melting then. It is a self-limiting process.
They were rabbiting on about this a long time ago, does it really take 5 years to design a computer program to manipulate the data to demonstrate some ratbag theory?
That would be five years of funding and therefore jobs , so what do you think?
“The study is the most realistic simulation of the climate system in which this type of early warning signal has been tested.”
Sorry. How the **** do they know that?
Models are useful as long as they are kept in their place. They are attempts to represent reality. They are not a substitute for reality. Climate science has given itself permission to make expensive public policy (expensive in terms of both personal liberty and money) based on models irrespective of how well the models can survive back testing. We know from the Climategate email trove that both the models and the data was manipulated to conform to ideological expectations. That is just plain corruption of truth. Climate science is clearly a modern form of Gaia worship and collectivism.
Now, the religion of CAGW is complete. The early warning signs of the end times have been revealed to us. We shall see the cooling from our warming and know it was our sins of emission that brought this apocalypse upon the world from Gaia.
Luckily as of 2010:
”NASA measurements of the Atlantic Meridional Overturning Circulation, part of the global ocean conveyor belt that helps regulate climate around the North Atlantic, show no significant slowing over the past 15 years. The data suggest the circulation may have even sped up slightly in the recent past.”
http://www.jpl.nasa.gov/news/news.php?feature=2534
Does a circulation speed up indicate Gaia is pleased with us? Shall we sacrifice more food to biofuels?
Now, this study actually makes some sense. Their model indicates that collapse of the AMOC is signaled by certain changes. This is a testable hypothesis. Go out and start gathering data – do some science. Let us know what happens. There should be more of this sort of thing.
“Experiments suggest that if the AMOC is ‘switched off’ by extra freshwater entering the North Atlantic, surface air temperature in the North Atlantic region would cool by around 1-3°C, with enhanced cooling of up to 8°C in the worst affected regions.”
The tangles that folk get into by neglecting solar variability in their models is pure tragicomedy. With reduced solar forcing, lower land temperatures will appear at the same time as the North Atlantic warms due to increased poleward ocean transport. That’s what happened since 1995 with the AMO.