Michael Mann and Stefan Rahmstorf claim the Gulf Stream is slowing due to Greenland ice melt, except reality says otherwise

UPDATED – see below

From your “Day after Tomorrow” department (where a slowing Gulf Stream turned NYC into an icebox) comes this claim from the bowels of Mannian Science. Unfortunately, it looks to be of the caliber of Mann’s Hockey Schtick science.
day-after-tomorrow

As WUWT reported on a peer reviewed paper last year, H. Thomas Rossby says: URI oceanographer refutes claims that climate change is slowing pace of Gulf Stream saying in a paper published in Geophysical Research Letters:

“The ADCP measures currents at very high accuracy, and so through the repeat measurements we take year after year, we have a very powerful tool by which to monitor the strength of the current,” said Rossby. “There are variations of the current over time that are natural — and yes, we need to understand these better — but we find absolutely no evidence that suggests that the Gulf Stream is slowing down.

Of course, Rahmstorf and Mann don’t list Rossby’s study in their references, nor seem to use the “highly accurate” ADCP data. Instead they use a model along with [proxies, reconstructions, and] the highly interpolated GISS data to come to the conclusions they want. So, it isn’t surprising they are chasing phantoms in their study. They claim (in Figure 1 from their paper) that this cold spot south of Greenland is caused by meltwater from Greenland and it is evidence of a slowed circulation:

Mann-Rahmstorf-cold-spot

Linear trends of surface temperature since AD 1901. Based on the temperature data of NASA GISS (ref. 48). a, Global equal area map (Hammer projection) for 1901–2013; white indicates insufficient data. b, Same analysis for the North Atlantic sector for 1901–2000. In addition to the observed temperature trends b also shows the grid points (black circles) of the subpolar-gyre region for which time series are shown in Figs 3 and 5, as well as the model-average 2 °C cooling contour (white) from a climate model intercomparison1 in which the models were subject to a strong AMOC reduction induced by adding a freshwater anomaly to the northern Atlantic. The geographic extent of the model-predicted temperature response to an AMOC reduction coincides well with the region of observed twentieth-century cooling. The models are forced more strongly and cooling extends further west as a result of shutting down Labrador Sea convection, which has only briefly happened in the real world so far. (Note that the second cooling patch in central Africa is in a region of poor data coverage and may be an artefact of data inhomogeneities.)

I find it interesting that they note “…that the second cooling patch in central Africa is in a region of poor data coverage and may be an artefact of data inhomogeneities.” Yet somehow that cooling patch south of Greenland is free of such problems in the same GISS dataset. Go figure.

And then there’s this other problem; Greenland’s ice mass seems to be on the increase so far this year and above the 1990-2011 mean:

Greenland-surface-mass-budgetSource: http://www.dmi.dk/uploads/tx_dmidatastore/webservice/b/m/s/d/e/accumulatedsmb.png

Accessed from http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/

Maybe this is the new Mannian science, wherein global warming causes cooling, and melting causes more ice accumulation. (h/t to Tom McClellan)

Of course, given that Stephan Rahmstorf thinks the “Day After Tomorrow” was just peachy, one wonders if this study isn’t just a embellishment of his movie review:

(Via Wikipedia) However, Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research, expert for thermohaline ocean circulation and its effects on climate, was impressed how the script writer Jeffrey Nachmanoff was well informed about the science and politics of global climate change after the talk with him at the preview of the film in Berlin. He stated: “Clearly this is a disaster movie and not a scientific documentary, the film makers have taken a lot of artistic license. But the film presents an opportunity to explain that some of the basic background is right: humans are indeed increasingly changing the climate and this is quite a dangerous experiment, including some risk of abrupt and unforeseen changes. After all – our knowledge of the climate system is still rather limited, and we will probably see some surprises as our experiment with the atmosphere unfolds. Luckily it is extremely unlikely that we will see major ocean circulation changes in the next couple of decades (I’d be just as surprised as Jack Hall if they did occur); at least most scientists think this will only become a more serious risk towards the end of the century. And the consequences would certainly not be as dramatic as the ‘super-storm’ depicted in the movie. Nevertheless, a major change in ocean circulation is a risk with serious and partly unpredictable consequences, which we should avoid. And even without events like ocean circulation changes, climate change is serious enough to demand decisive action. I think it would be a mistake and not do the film justice if scientists simply dismiss it as nonsense. For what it is, a blockbuster movie that has to earn back 120 M$ production cost, it is probably as good as you can get. For this type of movie for a very broad audience it is actually quite subversive and manages to slip in many thought-provoking things. I’m sure people will not confuse the film with reality, they are not stupid – they will know it is a work of fiction. But I hope that it will stir their interest for the subject, and that they might take more notice when real climate change and climate policy will be discussed in future.” Source: http://www.pik-potsdam.de/~stefan/tdat_review.html

But…

In 2008, Yahoo! Movies listed The Day After Tomorrow as one of Top 10 Scientifically Inaccurate Movies. The film was criticized for depicting several different meteorological phenomena occurring over the course of hours, instead of the possible time frame of several decades or centuries.

UPDATE: I’ve added figures 5 and 6 from the Mann and Rahmstorf paper below.

Mann-Rahmstorf-temp-proxies-fig5

Figure 5. A compilation of different indicators for Atlantic ocean circulation. The blue curve shows our temperature-based AMOC index also shown in b. The dark red curve shows the same index based on NASA GISS temperature data48 (scale on left). The green curve with uncertainty range shows coral proxy data25 (scale on right). The data are decadally smoothed. Orange dots show the analyses of data from hydrographic sections across the Atlantic at 25° N, where a 1 K change in the AMOC index corresponds to a 2.3 Sv change in AMOC transport, as in based on the model simulation. Other estimates from oceanographic data similarly suggest relatively strong AMOC in the 1950s and 1960s, weak AMOC in the 1970s and 1980s and stronger again in the 1990s (refs 41, 51).

Mann-Rahmstorf-accumulation-discharge-fig6

Figure 6 Mass balance terms of the Greenland Ice Sheet. Data from Box and Colgan33. Cumulative anomaly relative to the mean over 1840–1900, a pre-industrial period during which the Greenland Ice Sheet was approximately in balance.

When actual Gulf Stream measurement data (the ADCP data cited by Rossby 2014) is available, why would Mann and Rahmstorf use proxies? And why try to say that temperature is the indicator, when you have actual speed data? The obtuseness boggles the mind.

Further, note Figure 6, they claim that discharge exceeds gain, which looks like Mann’s proverbial “hockey stick” and this is based on Box and Colgan (2010) data, which is their citation #33. They claim data all the way back to 1850, which is quite some feat since as far as I know, no actual whole Greenland ice data was measured until the International Geophysical year of 1958, such as:

Bauer, A., Baussart, M., Carbonnell, M., Kasser, P., Perroud, P. and Renaud, A. 1968. Missions aériennes de reconnaissance au Groenland 1957-1958. Observations aériennes et terrestres, exploitation des photographies aeriennes, determination des vitesses des glaciers vělant dans Disko Bugt et Umanak Fjord. Meddelser om Grønland 173(3), 116 pp.

And further, previous papers from Jason Box only start with data at 1958:

Rignot, E., J.E. Box, E. Burgess, and E. Hanna (2008), Mass balance of the
Greenland ice sheet from 1958 to 2007, Geophys. Res. Lett.,35,L20502, doi:10.1029/2008GL035417

It turns out Box and Colgan (2010) is a reconstruction, not actual measurement data.

However, even more puzzling, when you look at the Box and Colgan (2010) Figure 5 from their paper (free PDF here) the mass balance loss and accumulation shows no such “hockey stick” shape.

Box-Colgan-2010-Figure5One wonders if Mann didn’t apply his “special Mannomatic math“, as he did to his “hockey stick” to the Box and Colgan (2010) reconstructed data to get the large divergence between accumulation and loss we see in Mann and Rahmstorf’s Figure 6.

More importantly though, the Box and Colgan (2010) data isn’t actual measurement data, it is a reconstruction based on some data, and some guesses:

According to our reconstruction, TMB has been positive for 39% of the 1840–2010 period (see mass balance surplus areas in Fig. 5). The positive decade-scale mass balance phases correspond with periods of low melting and runoff. For example, from 1970 to 1985 a positive mass balance phase corresponds to a period of enhanced sulfate cooling (Wild et al. 2009) pronounced along west Greenland (Rozanov et al. 2002; Box et al. 2009). Mass budget surpluses can also be produced by high accumulation years, even occasionally despite relatively high runoff (e.g., 1996).
The reconstructed TMB values are compared 1) with those from the surface mass balance in Part II minus the Rignot et al. (2008, 2011)LM for 20 samples spanning 1958–2009 and 2) with the independent GRACE data spanning 2003–10 after Wahr et al. (2006) (Fig. 6). We find RMS errors of 31Gtyr for dataset 1 and 69Gtyr in comparison with dataset 2 (Table 1).

So, clearly, there’s no actual data prior to 1958. The Mann and Rahmstorf paper misleads the reader by not making this clear.

Duke University physicist Robert G. Brown, in comments noted:

Seriously — they found “good evidence” that such a slowing is occurring, only the actual evidence, consisting of the measured speed of the Gulf Stream itself, shows no such thing?

The cognitive dissonance involved is stupifying.

Indeed. Mann and Rahmstorf eschew reality for models and reconstruction. They live in an incestuous climate world of their own making.

Here’s the press release:


Atlantic Ocean overturning found to slow down already today

Potsdam Institute for Climate Impact Research (PIK)

The gradual but accelerating melting of the Greenland ice-sheet, caused by man-made global warming, is a possible major contributor to the slowdown. Further weakening could impact marine ecosystems and sea level as well as weather systems in the US and Europe.

“It is conspicuous that one specific area in the North Atlantic has been cooling in the past hundred years while the rest of the world heats up,” says Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research, lead author of the study to be published in Nature Climate Change. Previous research had already indicated that a slowdown of the so-called Atlantic meridional overturning circulation might be to blame for this. “Now we have detected strong evidence that the global conveyor has indeed been weakening in the past hundred years, particularly since 1970,” says Rahmstorf.

Because long-term direct ocean current measurements are lacking, the scientists mainly used sea-surface and atmospheric temperature data to derive information about the ocean currents, exploiting the fact that ocean currents are the leading cause of temperature variations in the subpolar north Atlantic. From so-called proxy data – gathered from ice-cores, tree-rings, coral, and ocean and lake sediments – temperatures can be reconstructed for more than a millennium back in time. The recent changes found by the team are unprecedented since the year 900 AD, strongly suggesting they are caused by man-made global warming.

“The melting Greenland ice sheet is likely disturbing the circulation”

The Atlantic overturning is driven by differences in the density of the ocean water. From the south, the warm and hence lighter water flows northwards, where the cold and thus heavier water sinks to deeper ocean layers and flows southwards. “Now freshwater coming off the melting Greenland ice sheet is likely disturbing the circulation,” says Jason Box of the Geological Survey of Denmark and Greenland. The freshwater is diluting the ocean water. Less saline water is less dense and has therefore less tendency to sink into the deep. “So the human-caused mass loss of the Greenland ice sheet appears to be slowing down the Atlantic overturning – and this effect might increase if temperatures are allowed to rise further,” explains Box.

The observed cooling in the North Atlantic, just south of Greenland, is stronger than what most computer simulations of the climate have predicted so far. “Common climate models are underestimating the change we’re facing, either because the Atlantic overturning is too stable in the models or because they don’t properly account for Greenland ice sheet melt, or both,” says Michael Mann of Pennsylvania State University in the US. “That is another example where observations suggest that climate model predictions are in some respects still overly conservative when it comes to the pace at which certain aspects of climate change are proceeding.”

No new ice-age – but major negative effects are possible

The cooling above the Northern Atlantic would only slightly reduce the continued warming of the continents. The scientists certainly do not expect a new ice age, thus the imagery of the ten-year-old Hollywood blockbuster ‘The Day After Tomorrow’ is far from reality. However, it is well established that a large, even gradual change in Atlantic ocean circulation could have major negative effects.

“If the slowdown of the Atlantic overturning continues, the impacts might be substantial,” says Rahmstorf. “Disturbing the circulation will likely have a negative effect on the ocean ecosystem, and thereby fisheries and the associated livelihoods of many people in coastal areas. A slowdown also adds to the regional sea-level rise affecting cities like New York and Boston. Finally, temperature changes in that region can also influence weather systems on both sides of the Atlantic, in North America as well as Europe.”

If the circulation weakens too much it can even break down completely – the Atlantic overturning has for long been considered a possible tipping element in the Earth System. This would mean a relatively rapid and hard-to-reverse change. The latest report by the Intergovernmental Panel on Climate Change (IPCC) estimates there to be an up to one-in-ten chance that this could happen as early as within this century. However, expert surveys indicate that many researchers assess the risk to be higher. The study now published by the international team of researchers around Rahmstorf provides information on which to base a new and better risk assessment.

###

Article: Rahmstorf, S., Box, J., Feulner, G., Mann, M., Robinson, A., Rutherford, S., Schaffernicht, E. (2015): Evidence for an exceptional 20th-Century slowdown in Atlantic Ocean overturning. Nature Climate Change (online) [DOI:10.1038/nclimate2554]

Weblink to the article: http://dx.doi.org/10.1038/nclimate2554

Abstract

Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change. Maps of temperature trends over the twentieth century show a conspicuous region of cooling in the northern Atlantic. Here we present multiple lines of evidence suggesting that this cooling may be due to a reduction in the AMOC over the twentieth century and particularly after 1970. Since 1990 the AMOC seems to have partly recovered. This time evolution is consistently suggested by an AMOC index based on sea surface temperatures, by the hemispheric temperature difference, by coral-based proxies and by oceanic measurements. We discuss a possible contribution of the melting of the Greenland Ice Sheet to the slowdown. Using a multi-proxy temperature reconstruction for the AMOC index suggests that the AMOC weakness after 1975 is an unprecedented event in the past millennium (p > 0.99). Further melting of Greenland in the coming decades could contribute to further weakening of the AMOC.

Further information:

NASA animation “The Great Ocean Conveyor Belt” (downloadable video that shows the current system that now is found to slow down in the North Atlantic):

Weblink to a study on possible impacts of a shutdown of the thermohaline circulation: http://link.springer.com/article/10.1007%2Fs10584-009-9561-y

Weblink to the expert assessment of an AMOC tipping: http://www.pnas.org/content/early/2009/03/13/0809117106.abstract

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

305 thoughts on “Michael Mann and Stefan Rahmstorf claim the Gulf Stream is slowing due to Greenland ice melt, except reality says otherwise

  1. Nonsense. This is exactly what Bill Gray said would happen almost 40 years ago. The AMO as measured by Klotzbach and Gray is already negative. The water off Africa and the Main Development regions has cooled dramatically the past few years as we are in the end game of the Altantics warm cycle. This idea borders on delusional, an attempt to self verify the idea that co2 is actually influencing the oceans, laughable since the heat capacity of the oceans is 1000x air, and co2 is only .04% of the air.

    You are dealing with people that dont look at anything that can challenge them and have the same approach as spoiled children on a playground who insist on having their way.

    • During the early 70s we were in the midst of the ice age scare and the earth was definitely not warming
      and the gulf stream begain to slow down. That is too funny, they have obviously lost the plot.

      • I don’t think they care about the plot. They got what they wanted, a pro-AGW headline. Now their minion can go forth and proclaim the record cold and snow seen by Boston and NY were caused by AGW, and their political agenda moves forward.

    • I made this comment to this post http://junkscience.com/2015/03/22/celebrity-science-scientific-integrity-a-note-from-mel/ over at JunkScience.
      It seems to apply.

      Gunga Din | March 22, 2015 at 2:40 pm | Reply

      Will Rogers once said, “Everybody’s ignorant…only on different subjects.”
      Someone else once said, “It’s what you learn after you think you [know it all] it all that matters.”
      Humility, to recognize that one doesn’t know everything there is to know about anything (and that what they do know might be wrong) is a noble virtue.
      Too many celebrity scientist lack that. To give a hint that they might not know everything about their field is, to them, a sign of weakness rather than a sign of honesty. That can carry over to their opinions regarding things outside their field.
      Look at Michael Mann. He’s rejected any criticism by statisticians or other experts in their fields because, well, he just knows he’s right.

    • “Hey Joe, where you goin’ with that pun in your hand”. There a Jimmy Hendrix moment.

      Anyhow now I’m no scientist but the great AGW excuse for the record (since 78) Antarctic sea ice has been this thing about the freshwater land ice melting rapidly and cause a higher freezing point of the surrounding oceans thus more ice. I note that the article says as it tries to tell us that the gulf stream is being effected is.

      “like runoff from the ice caps in Greenland, which are now melting faster than anyone expected.”.

      So if fresh water run off from the “unprecedented” land ice sheets in Antarctica is causing record sea ice levels in the southern ocean then why are we not seeing the same affect around the coast of Greenland as Rahmstorf and co tell us that melting in the same disastrous way as Antarctica yet no sea ice positive anomalies here.

      There AGW loons really want their cake and to heat it

    • Why is it that, when a graph, or a map with coloured iso-whatevers, is – possibly, perhaps – intended to misdirect, so seeming to expound, whilst actually make obscure – the colours are run together so that deciphering it is j o l l y hard work.

      And yet – if it is intended to bring a clear picture to the reader’s attention, the scale, the colours, the background, everything – are as clear and transparent as the purest, freshest mountain air.

      And, yeah, in case Mr Moderator is wondering, I do – so very, VERY much, – believe in coincidences.
      [Yeah, right. /Sarc]

      Auto – with rose coloured glasses a distant memory.

  2. The North Atlantic must have really cooled down when the Vikigs settled Greenlland and when the island was much warmer than it is now. Imagine all the fresh water and icebergs that were flowing off Greenland back then. The Gulf Stream must have slowed to a crawl.

    • Since the MSM is apparently so enamored with the “science” coming out of CAGW computer models, maybe we skeptics should clobber together our own computer models, showing how easy it is to fiddle with equations and boundary conditions to get whatever is desired.

  3. imho, Mark Steyn must be wrong about Michael Mann.
    Mikie must be a gotdang freakin genius.
    Who else knew you could measure the Gulf Stream with tree rings?
    I wonder which tree he used this time?

  4. Earths rotation and wind drives the surface currents. An Icon of the alarmists has shot this nonsense down but sadly i cannot remember the link. If the posited theory was correct we would have no need to dam rivers, just run a saltwater hose into them.

    • The global warming/climate change alarmists seem to be using a tactic I saw in a high school debating contest coaching session.
      “Speak very quickly, bring up as many points as possible. That way, your opponents will not have enough time to make their own case and counter all of your arguments in the time allotted.”
      It seems we are being subjected to a tsunami of global warming/climate change drivel.

  5. I actually went and looked at the paper by Rossby, and there’s an important disconnect: the area od supposed slowdown (and hence cooldown) in Rahmstorf and Mann’s figure does not overlap with the transect along which Rossby meaured the current (between Bermuda and New Jersey). Hence, without saying Rahmstorf and Mann are wrong or right, their conclusion is not incompatible with Rossby’s paper.

  6. You, know, its never going to end. Its like the Knight guarding the bridge in Monty Python. No matter how much you chop it up, he is still going to think he wins. Except at least he had the courage to fight in public. None of these people dare take on anyone that can easily counter their arguments. I am amazed because its like they dont even look at the counters to their ideas, and they are so easy to find. BTW the cold water near Greenland promotes a trough in the means in the winter there, countering the very blocking that leads to the cold winters in Europe. Since this rapid drop in N Atlantic temps ( and now off Africa) we have seen 2 relatively mild Euro winters and the destruction of the Main Development Region burst in tropical cyclones which Gray properly forecasted back in the 70s for the 90s into the 2000’s ending by 2020. The massive NPAC warming, very similar to the late 1950s, has helped the Alaskan ridge for the cold eastern winters but it retards the blocking over Greenland by forcing strong mean trough over Eastern N america, which because of the warmth in the western atlantic, allows storms to bomb out near the east coast and then proceed ne for Greenland. I said countless times to the eastern snow lovers that follow me that once to mid winter on, that warm water off the east coast would be their friend not their foe, as the lament about lack of snow this winter in Mid Jan was constantly being directed at me ( We had a very snowy winter forecasted) Obviously that idea had merit ( nothing is perfect, but I do think we showed before hand). My point is that all this is linked and is well within the natural boundary of nature. It comes down to this. Does anyone seriously believe that the increase over a 100 year period of 1molecule of co2 out of 1,000,000 molecules of air is suddenly overcoming the sun, oceans, stochastic events and the very design of the system? And more to the point. how would the ocean, with 1000x the heat capacity of the air, be pushed around by those minute increases of what is only .04% of the atmosphere. It defies any realistic thought

    • Joe,
      the AGW nonsense does deify realistic thought, but don’t despair, it is going to end. Currently only the truly inane with little left to lose like Mann, Rahmstorf and Tremberth fight on, trying to claim dangerous warming threatens. Many others are pulling back, trying to save their sorry hides by engineering a “warming but less than we thought” soft landing for this inane hoax.

      The good news is that they will not be getting the soft landing they pray for, the soft landing some more foolish sceptics think to offer them. The laws of physics cannot be changed by any amount of propaganda. The big lie may have got halfway around the world before the truth had its boots on, but this is the age of the Internet, and the truth now arrives far more swiftly than before. Today the truth wears steel caps with hobnails. Alinskyites that try to create and maintain a “narrative” get stomped.

      At the very foundation of the “basic physics” of the “settled science” lays a hideous error that can never be hidden. Remember the foundation claims of the church of radiative climastrology? “Surface without atmosphere” at 255K being raised 33K by the addition of a radiative atmosphere? That claim is locked in. It can never be erased. The idiot warmulonians have made their bed and now they have to lay in it. How they got to the hideous mistake of 255K for “surface without atmosphere” is as painfully obvious as it was inane. They treated the surface as a “near blackbody” and entered 240 w/m2 into a standard Stefan-Boltzmann calculation with emissivity and absorptivity set to unity. Bingo, 255K! But that answer is totally and utterly wrong….

      71% of our planets surface is ocean, an extreme SW selective surface. Any engineer versed in solar absorption knows that for liquids that are SW translucent / LWIR opaque, free to convect and intermittently illuminated by solar SW, the Stefan-Boltzmann equation simply cannot work. The very foundation figure for “Surface without atmosphere” average should have been 312K not 255K. Current average? 288K. The net effect of our radiatively cooled atmosphere is therefore surface cooling. The climastrologists and their idiot fellow travellers got it so impossibly wrong it beggars the imagination.

      Climastrologists got the most basic calculation in the “basic physics” of the “settled science” about which “the debate was over” completely wrong*. No amount of propaganda, now amount of modelling, and no amount of fudged surface station data can ever hide the ultimate truth. This is the age of the Internet, the lame scream meeja are no longer the gatekeepers of opinion. The putrescent corpse of this sorry hoax cannot be re-animated, nor can it be hidden. This AGW inanity is not “too big to fail”. Lysenkoism failed even with the protection of the soviet state. In the age of the Internet, there is no hope for Gorebull Warbling or any of the fellow travellers.

      * If a ~60K error this bad in the very foundation of the radiative GHE hypothesis seems too incredible (and to some fearful lukewarmers it does), just remember that trying to use the Stefan-Boltzmann equation to determine average surface temp for the moon resulted in an error of ~90K when compared to Diviner empirical measurements. The problem was that superfine sharp edged, vacuum insulated basalt powder acted as a strange selective surface. Surface properties matter.

      Here’s what the engineers behind the Diviner mission did to check their instruments –

      Here’s what the climastrologists should have done to check their inane claims that the oceans would freeze without DWLWIR –

      – did they do it? No. Did they do even the simplest empirical checks to see if incident LWIR could slow the cooling rate of water free to evaporatively cool? Again No. Now the truth has its boots on they are in for a savage stomping, so too are any fellow travellers who tried to vilify sceptics into silence.

      • “The putrescent corpse of this sorry hoax cannot be re-animated, nor can it be hidden. “

        Nice prose. Frankenstein’s monster did destroy its master in the end, not in the literal sense but reputationally as society rejected the hideously grotesque creation. Victor then pursued his grotesque creation of all places… into the frozen Arctic. Even the way the way the monster was created is analogous to CAGW theory – stolen adultered (putrified flesh in your analogy) parts and secret formulas together with a violent storm and lightning.

        CAGW = Frankenstein’s monster, soon to be totally rejected by society. It creators vainly searching the Arctic cold for answers.

      • Konrad:

        Nice setup!

        Question for you on the picture. You seem to show 50% duty cycling at 1000 W/m2. This implies a time averaged 500 W/m2. Is that correct?

        If it is, then water with LW emissivity of 0.95 with no other losses and no ambient (“back”) radiation would average at about 312K, which I believe you are saying you found.

        But that would be about twice the time-averaged and surface-averaged radiative flux hitting the earth. Have you repeated the experiment with, say, a 25% duty cycle for a time-averaged 250 W/m2?

    • I apologize in advance for this pedantic moment…

      Actually the Black Knight and the Bridgekeeper were two different folks. Thinking about it though, either character works as Mann. Picture Mann as the Bridgekeeper- finally getting tripped up on his own question and tossed into the volcano, heh.

      • I pictured him balancing on one leg, blood spurting from where his other three limbs were, still convinced his victory was forthcoming.

    • Joe Bastardi, Bob Tisdale

      Since this rapid drop in N Atlantic temps ( and now off Africa) we have seen 2 relatively mild Euro winters and the destruction of the Main Development Region burst in tropical cyclones which Gray properly forecasted back in the 70s for the 90s into the 2000’s ending by 2020. The massive NPAC warming, very similar to the late 1950s, has helped the Alaskan ridge for the cold eastern winters but it retards the blocking over Greenland by forcing strong mean trough over Eastern N america, which because of the warmth in the western atlantic, allows storms to bomb out near the east coast and then proceed ne for Greenland.

      There is some circulation up (north) through the Bering Straits from the northwest Pacific through the Arctic Ocean (under the sea ice obviously) then down (south) into the Atlantic. Is part of today’s reduced sea ice off of both sides of the Kamchatka Peninsula (the southern Okhotsk coast and in the northern part of the Bering Sea) due to an influx of the last fall and summer’s “very warm” northwest Pacific bubble up north during Dec-Jan-Feb?

  7. The Gulf Stream is driven by surface winds (and then confined by the continental shelf that is at least 200 metres deep).

    It is driven across the Atlantic from Africa to the Gulf of Mexico by the Trade Winds. It is then runs up to the 200 metre depth continental shelf of North America, is squeezed along Florida into the North Atlantic. The water is constantly flowing in and it has to keep flowing out.

    It then picks up the winds now moving south-west to north-east flowing off of North America and this drives it all the way back across the Atlantic to the north side of Europe.

    The Gulf Stream is always going to flow as long as the Earth is rotating, setting up a certain pattern of winds and confined by continental margins.

    Has the Earth changed its rotation. Did the continents move. Did the winds slow down.

    • The Gulf Stream starts here.

      Then here.

      It is driven by surface winds, not the thermohaline deep ocean circulation system.

      • Very cool. Especially like the mayhem in the last one.

        As Peter Berenyi and others have pointed out have pointed out, the thermal/saline density gradient is waaay too small to actually drive the THC. Wind is a likely candidate again, particularly the Antarctic vortex working as a centrifugal pump.

      • Interesting, and makes sense. The wind does indeed blow the top 5 m of water, and no doubt lower levels follow along.

        And I noted in the NASA simulation that the syncline of the surface waters was driven as much by the ocean floor topography, as the temperature. I mean, if you drive down a cul-de-sac at some speed, where are you going to go when you meet the barriers at the end….?

    • Bill, does the 900 mph rotation of earth at the equator exert a greater force on the air or water?

    • No, its driven by the earths rotation, as is the earths trade winds. the winds augment it. It is only the boundary condition, where it finally loses energy and sinks that fluctuates due to temperature/density variations.

      • Mr. Lensman sir:

        “No, its driven by the earths rotation, as is the earths trade winds. the winds augment it.”.

        With all due respect, I do not believe it is correct to say that the rotation of the earth drives the trade winds or the oceanic circulation gyres.
        My understanding is that the sun provides the energy which begins the motion of the atmosphere.
        Air rising in response to solar heating near the equator causes the motion of the Hadley cells. As the rising air reaches it’s maximum altitude and begins to move poleward, this is where the effect of the Earth’s rotation show up. Ditto for the air which moves in to replace the rising air…the trade winds. Air moving north or south appears, from the vantage point of a surface observer, to move in a curve, in order that angular momentum is conserved.
        Coriolis is only an apparent force, not a source of energy per se. Inertia man, no getting away from it.
        Same goes for water as for wind…if it moves north or south, it is deflected to the right in the NH, and to the left in the SH.

    • WHEN the Gulf Stream slows down, as sometimes during ice age glacials, water near Florida warms up. Were Florida waters warming we would have more hurricanes. The water isn’ t, and we don’t.

      There was an open access paper on this that dissapeared behind a paywall after I linked to it a couple of years ago… well researched paleo weather history of Florida showing counter cylical with N. Europe and Gulf Stream flow changes. The link I have is now dead, though I have a couple of quotes saved in the article I wrote then. Florida winter goes to summer pattern weather as the flow slows, so more thunder storms. (now winters are more dry) Also the pollen shifts as the oak to pine ratio shifts. Slow Gulf Stream lets the shallow Gulf of Mexico accumulate / keep more of the solar heating.

      So until there are more reports of excess winter rain and more hurricanes in Florida, the Gulf Stream is still running as recent norms predict.

      • Found that Florida paper… looks like the guy moved to a new .edu … It was first linked by me in a posting here:
        https://chiefio.wordpress.com/2012/12/15/d-o-ride-my-see-saw-mr-bond/

        but is now found at this link:

        http://www.geology.um.maine.edu/publications/Jacobson%20et%20al.%202012%20Hg%20in%20L.%20Tulane%20ES%26T%2046%20%2011210-11717%5b1%5d.pdf

        There are a couple of nice graphs in it (one shows oaks vs pines and you can see the pines take over as the holocene kicks in, with peaks of pine at the Holocene Optimum, then a drop, and a recent small rise in oaks as we’ve started the cooling of the LIA. He also studies Mercury deposition that has a nice peak at the Holocene Optimum too… It also shows “recent warming” as a hair of a blip on the end of a long cooling past the H.O. peak, and just barely out of the LIA. The paper does worry that the Hg peak might be an error due to something being different in Hg flow then, and it might be… or maybe it was just hotter…

        All in all a little known but interesting confirmation of the LIA and H.O. and that recent “warming” is nearly nothing.

        At any rate, Florida is presently warm, but not exceptionally so, and when the Gulf Stream shuts down or slows a lot, there ought to be heat build up in the Gulf of Mexico and Florida reflected in warmer wetter conditions ( unlike a decade or so back when John’s Lake completely dried up due to low rainfall… indicating it was warmer in Europe then, but colder and dryer in Florida. You remember, when it froze so much the Iguana were falling out of their trees… )

        Watch for such inverse linkages as the Warmers will try to use them “straight” to claim warming is continuing when it really is cooling… Like California drought that happens when the water off shore is colder (as in the ’70s droughts and as in the early near LIA era megadroughts). How they can claim warmer water makes more precipitation as snow but less as rain is an interesting study in bafflegab… just have to ignore the actual water temperatures and the jet stream changes… and reality…

      • Mr. Smith, I think that it is important to point out that there will only be more hurricanes is the conditions of the atmosphere permit them to form and persist.
        They need, in addition to warm water, relatively light winds at different levels of the atmosphere, and sufficient moisture at various levels to allow convection be maintained for long enough to allow a closed circulation to form.
        Wind shear will tear them apart no matter the water temp if upper level winds are strong, and areas of dry air will prevent formation, and/or strengthening, even when other conditions are met.
        I recall well the very day in 2004 when it seemed that someone hit a switch. I think what happened is that upper level winds slackened suddenly, and the impulses which where already there had nothing holding them back. It was quite a thing to be living in South Florida for the rest of that season and all of the next.
        Now, I do not mean to say that you are incorrect to say warmer waters near Florida will lead to more hurricanes, just that this is not the whole story.
        It may be that a cooler world has lighter winds in the upper atmosphere of the tropics, and hence more hurricanes that a warmer world, in which the upper level winds may be stronger in response to the increase in available energy.

  8. “Now freshwater coming off the melting Greenland ice sheet is likely disturbing the circulation,” says Jason Box of the Geological Survey of Denmark and Greenland. The freshwater is diluting the ocean water.

    The freshwater is diluting the ocean water?

    How much freshwater as rainwater dilutes the ocean water on a daily, monthly, or yearly basis?

    This crew sounds like Bill Nye The Science Guy on Larry King with Richard Lindzen eight years ago:

    At 00:45 seconds, Nye cites An Inconvenient Truth as stating that when the ice caps melt and that freshwater flows into the sea, it upsets the thermohaline ocean circulation, and the “oceans get bigger,” because “when it gets warmer, warm things expand.”

    Richard Lindzen at 1:34 minutes says, “Nye was talking about perhaps freshwater shutting down the Gulf Stream, but that isn’t what physical oceanographers think . . . the Gulf Stream is mostly driven by wind. To shut it down you’d have to stop the rotation of the earth or shut off the wind.”

  9. Greenland’s ice mass seems to be on the increase so far this year and above the 1990-2011 mean.

    Well, doesn’t that prove that Greenland really is surrounded by unusually cold water?

    It’s obviously a sign of a positive feedback.

  10. First rule of climate ‘science’ when reality and the models differ its reality which is in error , so they are merely working to the rules and at the simply awful ‘standards ‘ not just acceptable but honoured within climate ‘science’ The fact its first class cra* is merely a side issue.

  11. So if the gulf stream is not slowing, where does the warm flow go during a slow AMOC event?
    It accumulates in the north Atlantic and spills into the Arctic instead of overturning.

    Low AMOC events tightly correlate with negative NAO episodes, e.g. early summer 2007 and mid summer 2012, and cold winter months in 2010 and March 2013:
    http://www.rapid.ac.uk/

    IPCC models predict increasingly positive NAO with increased GHG’s.

    Seas south of Greenland warm up from these negative NAO episodes:
    http://weather.unisys.com/archive/sst/

    Demonstrate a solar forcing of the NAO, and that would tie the whole thing up.

  12. “Read the Paper”? I couldn’t get past the first line of the press release:

    “The gradual but accelerating melting of the Greenland ice-sheet, caused by mann-made global warming”

    Signed killed and delivered, what’s there to read?

    And the song goes: “The arm bone’s connected to the hand bone” and the oceans are connected to everything else.. Ammen!

      • I agree which is probably why you might think about changing your handle to willfulignoranceandIlikeit.

        Also agree with the badge of honor idea, you could make willful ignorance badges and sell them on eBay. A picture with you wearing the badge would sell tons.

        Well, what about that, huh?

      • The premise that the Greenland Ice sheet is decreasing immediately debunks the paper when it claims the opposite (from reality) thus it is very safe to throw the paper in the trash…

      • “Willful ignorance” is the only thing keeping normal people from wasting time learning about stupid things, like crop circles, UFOs, bigfoot, ghosts, or this lightweight paper designed to be more propaganda than science.

      • Shinku. Have a look at GRACE data to see how much ice Greenland is losing.

        Those assumptions from the GRACE satellites are based on assumptions of land rebound approximations under the Greenland and Antarctic ice caps. The land rebound is not measured, and not based on mid-field ice cores, but on assumed ice loss. Thus, because the ice mass is assumed to be reduced, the land is assumed to be rising under the ice, and thus the ice is “measured” being lost. The actual data from GRACE doesn’t actually measure ice loss.

      • (Snip. You have been repeatedly warned about labeling others as “deniers”. Commenting here is a privelege, not a right. Since you have a hard time learning the site Policy, your comments for the 24 hours surrounding this post will be snipped. When you’re out of the doghouse, please keep the site Policy in mind. -mod)

        [Anthony, this is a previously banned sockpuppet. You know who. ~mod]

  13. From the paper:

    The authors declare no competing financial interests.

    Bwahahaha You mean, someone’s going to pay Mann NOT to write this kind of stuff? Then again, interesting use of the word ‘competing’.

    • It says — no financial interests compete with their paper

      No one is paying anyone else to dispute their paper

      It also implies that someone is paying them to write the paper

      They are being paid and there are no competing financial interests paying others.to dispute their paper

      Amusingly it says that skeptics don’t get paid for their work. And truly, no skeptics got paid for ripping this worthless paper apart.

      Mann doesn’t lie all the time. Sometimes he accidentally tells the truth.

      Eugene WR Gallun

      • Eugene WR Gallun
        March 24, 2015 at 7:10 am

        It also implies that someone is paying them to write the paper

        That phrasing also means/only means that the people who paid the authors AGREED (in advance ?) with the purpose and premise and conclusions written into the article; and indicates those people paying for the article apparently agreed with the purpose, premise, and conclusions of the article before the agreement to pay for the article was made, and thus both the conclusion and the agreement were made before the article was written.

      • It bears noting that in discussions such as this one, as well as most others on skeptical websites and blogs, the source and/or fact of a person’s funding is noted, but only in passing, while the science is taken apart piece by piece and in great detail.
        On warmista sites, funding is the beginning and end of the conversation for many commenters. IOW, it is all one needs to do, to point out funding. Same with any number of prior affiliations one might have.
        “Well, the author’s daughter’s teachers nephew once mowed the lawn of a guy who works at The Heartland Institute, so I think that says all we need to know about this paper.”

  14. PS: I note you have to pay to see who the reviewers were. Odds on they are anonymous anyway.

    • Well, it would only be polite.
      They must be rather embarrassed about missing the relevance of the Rossby paper.

      I’m sure Nature will investigate how they found themselves with such unqualified reviewers but there’s no reason to humiliate them, is there?

      Let’s just ask Nature how their investigation is going.

      • M Courtney

        I assume in your statement “Nature will investigate how they found themselves with such unqualified reviewers but there’s no reason to humiliate them, is there?”, the last “them” refers to the poor unqualified reviewers.

        I have no problem with being held accountability (or holding others accountable), but then I’m a retired CFO; auditors, public disclosure and Wall St Journal headlines loomed around every corner. I guess in academe people are too polite to disclose who did the review, or (god forbid!) to publicly comment if a reviewer really screwed the pooch. I won’t waste a whole lot of words on oblivious unqualified professionals who aren’t self aware enough to realize (or care) that they are…wait for it… unqualified.

        The ongoing academic lack of accountability just amazes me.

    • List of probable anonymous reviewers:
      Stefan Rahmstorf, Jason E. Box,Georg Feulner, Michael E. Mann, Alexander Robinson, Scott Rutherford,
      Erik J. Schaffernicht.

  15. The first sentence of the abstract is a gem [my bold]:

    Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change.

    They missed out ‘perhaps, could, maybe’, and the best: ‘you never know’.

    • Harry, what we really have here is Michael Mann running AMOC in the field of science. Again.

      This latest effort by Mann is so risible that I was immediately reminded of that great scene in Annie Proulx ‘The Shipping News’. When the risk of some fluffy white cumulus clouds on the horizon actually being a ‘Deadly Storm’ that ‘Threatens Town’, as speculated by the local newspaper publisher, is suggested as being ridiculous it is laughed off as being immaterial because then the prospective headline is ‘Town Saved From Deadly Storm’.

      Mann, the IPCC and all the cloud of CAGW insects will celebrate how they saved the Earth from CAGW when it is finally accepted that the science shows it was all a farrago of nonsense.

      I once read that society is actually defined by its outliers, its miscreants and deviants. It is how we know that we are doing the right thing. Michael Mann is one of those sad little lost souls that let the rest of us know we are not off our heads.

      He is Smeagol/Gollum to our Bilbo. Pity him.

      Such is life.

  16. When is Penn State University going to disown this unscientific propagandist? Or are they going to change their charter from an institution of higher learning to an institution of shoddy work and unsupported assertions?

    Where is the internal peer review on the quality of his work and accuracy of his conclusions? Very sad.

    • FTOP

      Excellent point. This peer review stuff might have worked in the middle ages when just a few guys in town could actually read tour stuff.

      Now days the academic community has out grown this gentle “self management” approach, because, among other things (according to climate gate email), reviewers first allegiance is to “the team”, not the science.

  17. From the above post I found the following quote from Stefan Rahmstorf discussing the movie, “The Hooey After Tomorrow” (oops, I meant day after tomorrow), really rather interesting.

    ‘For this type of movie for a very broad audience it is actually quite subversive and manages to slip in many thought-provoking things.’

    It’s funny how people give themselves away, most of the time without even knowing it. Notice the use of the word ‘subversive.’ To insure I understood the meaning of the word I looked it up using our ever trusty Wikipedia. The definition is copied below:

    ‘Subversion refers to an attempt to transform the established social order… Subversion (Latin subvertere: overthrow) refers to a process by which the values and principles of a system in place, are contradicted or reversed. More specifically, subversion can be described as an attack on the public morale… Subversion is used as a tool to achieve political goals because it generally carries less risk, cost, and difficulty as opposed to open belligerency. Furthermore, it is a relatively cheap form of warfare that does not require large amounts of training. A subversive is something or someone carrying the potential for some degree of subversion.’

    Yep, I’d say Rahmstorf has just given the whole CAGW game away with just one word.

  18. Gulf stream “slowing” would result in a quick cool-down of NW Europe & increased sea-ice. When that happens, wake us up. Just more fear-mongering.

    • If the Gulf Stream was slower, would it not linger in the tropics longer, and thus be hotter as it moved northward and, being hotter and moving slower, would this not allow more time and greater thermal gradient to transfer this heat to the overlying air, and thus be a net wash?

  19. Dr. Mann’s contribution to the paper seems to have been his proxy data and related statistical manipulations.

    To validate the proxy reconstructions of temperature we use standard techniques developed during the past two decades in the paleoclimate community.

    As usual, the accuracy of statistical techniques is presumed to increase the accuracy of his proxy analysis.

    The probability to get a value as low as the observed 1975‐1995 mean just by chance is thus the joint probability over the data uncertainty and the Monte Carlo distribution, i.e. the product of the two distributions shown, integrated over all temperature anomalies (i.e. the x‐axis). For the data shown this number is 0.45%, which implies a 99.55% significance of the 1975‐1995 AMOC reduction.

    The mind boggles.

    • Opluso: I get the feeling that a certain Canadian statistician is going to have field day on this. I do hope so.

  20. How does one scare the public without technically committing fraud?
    Weasel words, that’s how.
    “could impact marine ecosystems”
    “could have major negative effects”
    “could happen as early as within this century”
    “could contribute to further weakening ”
    “If the circulation weakens”
    “If the slowdown of the Atlantic overturning continues”
    “if temperatures are allowed to rise ”
    “overturning circulation might be to blame”
    “this effect might increase”
    “impacts might be substantial”
    “possible contribution of the melting”
    “Possible changes in Atlantic meridional overturning circulation (AMOC)”
    “possible tipping element in the Earth System”
    “global warming, is a possible major contributor”

      • Stop it Dan, my head is starting to hurt.
        BUT one thing’s for sure, this AGW now “Climate Change” topic is going to be a huge factor in the coming elections both here in the USA, Canada (Nov. ’15), Brittain etc. The schreeching from the left is going to be louder than ever seeing that more and more people are seeing through it and it is also far down on the list of worries but the problem is that it makes for great Video on TV in Political ads and TV ( Storms , big waves , torn houses, breaking trees etc) compared to people dying from shit,y healthcare or the lack of jobs, falling down bridges and breaking up of road decks etc
        Sadly we will see this type of hype increase everywhere and the attacks on viable candidates increase day by day!.

  21. When Climate Liars can’t think up new sciency-sounding nonsense, they dig up old, long-debunked nonsense, shiny it up, put lipstick on it, and hope it will fly. Or at least crawl.

    • Actually they hope the media will have a field day, promoting it for a week, while ignoring the critics, and then their propaganda will be considered successful, and they will get more funding. (sadly it appears to work)

  22. So if the Gulf stream is slowing down shouldn’t we be seeing more sea ice in the Barents Sea, not less?

  23. From the abstract:

    Using a multi-proxy temperature reconstruction for the AMOC index suggests that the AMOC weakness after 1975 is an unprecedented event in the past millennium

    Raises the question, what proxies? (I’m not paying to find out), and, how is that the ‘AMOC weakness after 1975’ has only just reared its head? If it’s so ‘unprecedented…in the past millennium’?

  24. Analyzing climate model data is right up there now with reading tea leaves.

    Actually I’ve heard, anecdotal of course, that reading tea leaves produces far more reliable results.

  25. From the Abstract:
    “Using a multi-proxy temperature reconstruction for the AMOC index suggests that the AMOC weakness after 1975 is an unprecedented event in the past millennium”

    Given that low AMOC events are inextricably linked to negative North Atlantic Oscillation episodes, and that increased GHG’s should increase positive NAO, they have shot themselves in the foot.

  26. Looking at the Gulf Stream where is shoots through between Florida and Cuba, sediment studies have shown that the Gulf Stream speeds up with warming and slows down with cooling, based on water viscosity. The assumption that melt water from Greenland would stop the flow begs the question of where the freshwater goes. It would follow the typical clockwise flow and head toward Europe and then south. As this state would be with warming, the northward Gulf Stream waters would be evaporating and becoming denser faster and likely need to sink long before it runs into the fresh water melt.

  27. I just sailed across the Gulf Stream twice. It was such a tremendous push I was shocked.
    According to the data I saw, it was actually stronger than it normally is in February when I crossed between the north side of Cuba and Mexico. Literally, boat stopping strong!

  28. I rarely comment in any article where either of these two jokers is mentioned because they are to Climate Alarmist Pseudocience what the Sky Dragon Slayers are to Climate Skeptic Pseudoscience. Indeed, I would pay good money to put Mann, Rahmstorf, Joe Olson, and maybe John O’Sullivan into an arena wearing lucha libre stretchy pants and broadcast the result on TV. Fully body slams, spinning kicks, neck-locks. Bill Nye can be the referee.

    Seriously — they found “good evidence” that such a slowing is occurring, only the actual evidence, consisting of the measured speed of the Gulf Stream itself, shows no such thing?

    The cognitive dissonance involved is stupifying. That’s why I rarely comment — it leaves me speechless (no easy task) and disgusted (pretty easy these days:-). And yes, Day After Tomorrow was easily one of the dumbest movies from a scientific point of view that I’ve ever watched a few minutes of before concluding that the plot, the science, the acting, the storyline, the writing, the premise, and the thrilling conclusion were not, actually, worth diverting my questing intelligence from the worthy activity of watching the grass grow or contemplating the pattern of veins and floaters visible when I close my eyes.

    The sad thing is that the hypothesis is a reasonable one, and has been around for a long time. It is one of the mechanisms proposed to explain the Younger Dryas — the breaking of an ice dam and draining of Lake Aggasiz:

    http://en.wikipedia.org/wiki/Lake_Agassiz

    interrupted thermohaline circulation and raised the sea level by 1 to 3 meters (yes, meters) suddenly, caused a true global cooling event in years circa 8200 BCE (and possibly in a distinct event the Younger Dryas circa 13,000 BCE) and may have been the origin of the flood myth, as a three meter rise in ocean level over decades may have been what flooded the Black Sea through the Bosperus (although the evidence for this is very mixed — the Black Sea was itself a huge freshwater glacial melt lake at around that time with comparatively rapidly varying level anyway).

    It is also “undeniably” true that in a chaotic climate, even small changes that have nothing to do with “global warming” can easily cause large natural shifts in things like the self-organization of circulation patterns and “rapidly” shift the climate.

    This makes any and all claims non-falsifiable. Hell, it’s worse than that! They might even be true! Chaos theory contains the moral equivalent of the homeopathic hypothesis or “smart water” — small fluctuations are amplified into — anything you want to claim! Hey, it is all possible! No limits! I sneeze, and in ten years the ice age cometh…

    rgb

    • Am I the only person who has NOT watched “The Day After Tomorrow” ? I regarded it’s viewing as a form of self abuse. Was I wrong? I feel the same whenever I read Mann’s writings… when and where it oozes out of its carbuncle here. GK

      • Don’t feel too self abused. Movie had stupid science but great special effects; enjoy those and forget the rest.

      • BFL
        March 24, 2015 at 9:21 am

        Don’t feel too self abused. Movie had stupid science but great special effects; enjoy those and forget the rest.

        Yes, the special effects were good enough to use a shot of styrofoam breaking appart CGI’ed into a glacier calving in his “An Incontinent Ruse” (where the BS never stops) but was “stupid science”. Not quite science fiction. More like fantasy.

      • My wife managed to enjoy it as a story, despite my constantly shouting “Are you kidding me??!!” at the TV throughout.

    • Yes, and that is precisely why chaos theory is a waste of time. Time? Now we’re getting somewhere. One rail of science since Pythagoras is that truth is universal, necessary, certain and timeless. Time does not exist. A more recent rail: Geological change, evolution (on many levels), and probability. On this rail truth is specific, relative, conditional, and time is of the essence.

      We zap between these rails seeking certain and timeless probability in the perhaps vain hope that time can somehow be cancelled in the equation.

    • Chaos theory contains the moral equivalent of the homeopathic hypothesis or “smart water” — small fluctuations are amplified into — anything you want to claim!

      Good Lord, I live in the Land of Homeopathy and All That Is Imbecilic. There are times when I feel like there is no escape. From Qigong, to essential oils, to herbs that can do more things than CO2, to accupuncture, to sound therapy, to karma cleansing, to chakras alignment, to naturopathy, to TCM, to wholistic everything, to aroma therapy, … that’s all there is. That’s all people talk about. That and showing Instagram photos of what they ate last.

    • As often here, people “refute” without looking at the time scales. Rahmstorf’s paper says (abstract):
      “Here we present multiple lines of evidence suggesting that this cooling may be due to a reduction in the AMOC over the twentieth century and particularly after 1970. Since 1990 the AMOC seems to have partly recovered.”

      So the “refutation” has Rossby saying:
      ” two decades of directly measured velocity across the current show no evidence of a decrease”

      And we are shown the last few years of Greenland ice melt.

      There is no dissonance – and no refutation.

  29. Two things:

    1) The pause has been eating away at the psychological health of the diehard core (various reports of climate blues). They’re now worried about cooling and this is their crippled way to get ahead of the cooling curve. You get it! If things continue to cool, then Mike and Stephan have some skin in the game. More to come, and the pied piper effect will be infecting the rest of them. Watch for NCAR, NOAA, Potsdam, Max Planck Inst., Wegener Inst., UEA, and the next IPCC report. I’m 95% certain of this. Anthony, open a department for rationalization of the cooling and tick them off as they come. This is number 1.

    2) The seriousness of this straw clutch insurance is that M has thrown the handle of his hockey stick under the bus (Steyn take note). He says this hasn’t happened since 900AD … wait for it… the last time Greenland was melting was during the Medieval Warming period!!! This is an Inuit hockey stick with a blade on both ends. Hey and guess what happened when the MWP ended.

    • As I said yesterday about Jerry Moonbeam Brown: The new hot-buttons of Climate Change will be “extreme cold”, because of the much bigger cold dollar damages to the economy that can be claimed from heavy snows and ice (e.g., in the North East US this winter).

    • That is catastrophic anthropogenic global yo yo. (When it is cooling it is CA, when it is warming it is CA,

  30. Okay, this seals the deal that Mann is a serial science fraud with model malpractice as the main tool.

  31. Anomalous snowfall in the Atlantic around Greenland has introduced more cold water into the ocean than any amount of melting can contribute.

  32. “Possible / could / may be due to / evidence suggesting / seems to / suggests that /could contribute / uncertainty / might be substantial / could have / observations suggest / is likely / might be to blame/ possible major contributor / this effect might / in some respects …”

    Anyhow, apart from that, the science is settled (in some likely, possible respects).

    • These are words and phrases used in the hypothesis stage. I hope for their own sake that they are not peddling this as settled science. DR;TL

  33. They don’t use satellite data because it has been found to show lower temperatures. They say it on their site.
    +++++++
    wow. they actually admit that the reason not to use satellites is because they show lower temps??? if so that is one of the most unscientific statements ever made. normally if different sources show different results, you want to incorporate this into your error and uncertainty calculations, not simply ignore one source in favor of the other. WOW!!

    • Particularly so since Greenland, with a km or so of ice on top of a km or so high plateau, experiences the directly and precisely measured (by satellite) mid-troposphere temperatures, not the corrupt land surface temperatures generated by NASA GISS or Hadley. They had a cow three years ago when Greenland actually experienced day or two where temperatures on the plateau went up TO freezing, which is indeed a rarity because it is damn cold up there.

      What I had not realized is until seeing the data above is that Greenland has apparently increased is low-water mark icepack by 250 Gt in only three or four years, if the graph is to be believed. Arctic sea ice doesn’t affect SLR, but icepack accrual on top of an icebound plateau that never gets above freezing is a rather big deal! That almost perfectly balances the assertions of land ice loss in Antarctica, to within maybe 10 Gt/year. Antarctica’s “warming trend” of 0.05C/decade (which is “significant” according to the wikipedia article on this subject) is supposedly responsible for the ice loss there, even though most of the ice loss comes from a single peninsula and there is a strong possibility that the heat source responsible is geothermal and coming up under the ice, not down from above it, as (sorry) surface temperatures have basically not varied in most of the continent and remain colder than a digger of local water service access points derriere, more than cold enough that the only substantial loss mechanism is direct sublimation as it basically never melts at the surface and is very, very, very cold at the surface almost all of the year. As in Minnesota is downright balmy compared to Antarctica on its mile+ high interior plateau with its enormously thick layer of ice.

      I sometimes think that people have completely forgotten how to do back of the envelope estimations, but if land ice is diminishing — and I mean the “if” as nobody ever shows error bars in climate science, they just make statements about numbers as if they are true and perfectly known and there is no question at all about the statistics or methodology used to get them — at only 10 Gt/year, it is going to take a long, long time for any significant SLR to occur due to land ice melt. The Arctic could become “ice free” and not affect SLR at all, but as long as the Greenland ice pack increases at 60+ or so Gt/year, we could even see SLR stabilize or drop for the first time in the observational record, although on longer timescales the ocean’s level fluctuates substantially from completely natural causes that are not anthropogenic CO_2.

      rgb

      • I sometimes think that people have completely forgotten how to do back of the envelope estimations

        Now you need a computer and software, never question the output and assume that the answer is 96.999999% correct.

      • “I sometimes think that people have completely forgotten how to do back of the envelope estimations,…”

        And I think you will often be correct, rgb. The MSM is usually incapable of performing a smell-test, but we should still expect better from others who anoint themselves with the title of climate-“scientist”.

      • rbg re ice sheets and SLR:
        Some rough data. The thickest part of the Greenland sheet is 3km, and the mean altitude is ~2km. Much of rock below the ice is near or at sea level. For Antarctica, similar mean altitude, thickest ice ~4.5km. Land of West Antarctica below the ice is as much as 2500m below sea-level. So for all the fuss, particularly concerning West Antarctica, a fair proportion of the ice is already displaced in terms of SLR. A second aspect is when you push a continent down into the mantle, the land bulges up around the periphery, already displacing a fair amount of the ice (ice SG ~1, sea crustal rocks ~3). Here is a cross section across Antarctica that illustrates this geometry.

        There is considerable volcanic activity below the ice of W. Antarctica and offshore and even to the north and north east of East Antarctica where much there is little known. I suspect the volcanics are enhanced and induced by the pressure created by mass of Antarctic ice and similarly in the case of Greenland where there has also been detected hot spots under the ice and sea floor volcanoes in a train southerly from Svalbard that, were apparently recently discovered. This and the volcanics on Iceland are probablay also enhanced by the pressure of on the mantle below Greenland. The volcanics are therefore, in part, likely some of the displacement of the ice mass. If the ice loss is going to be a slow affair taking thousands of years, isostatic rebound will reduce ~1/3 of the SLR.

    • UAH lower troposphere does not diverge from SST’s. The recent faster warming rates of continental interiors is due to precipitation changes due to the warm AMO mode.

  34. They don’t use satellite data
    ==============
    that is like using a single tree ring series as a proxy for the entire world because it just happens to match thermometer data some of the time, while ignoring all other tree ring series. just because something happens to match doesn’t mean it does so because it is accurate. a stopped clock gets the right time twice a day, while a running clock is rarely if ever exactly right.

    • Yeah, that one is one that bothers me enormously as well. Especially when I strongly suspect that they don’t even keep all of the tree ring data that matches the supposedly accurate (but really not) thermometric record. I mean thermometric “anomaly” record. Actually, I have no idea what I mean. Nobody does. The other great swindle in all of this is the illusion that given j = 1,2 readings from 100 thermometers at two different times the change in the average temperature at the two times:

      = \sum_i T_{ij}/100
      \Delta T =  -

      is less accurate than the average change in the temperature “anomaly” at the two times:

      = (T_{i1} + T_{i2})/2
      = \sum_i (T_{i2} - )/100 - \sum_i (T_{i2} - )/100,

      In particular that either one of the deltas is more accurate than either $latex $ itself. I keep going over this argument and I just don’t get it. You’re a stats guy, right? Is there something I missed learning in statistics that suggests that these two statements aren’t pure algebraic rearrangements of each other? The second average just cancels out one of the two terms and recovers the first form, does it not? Maybe I need to sit down with paper because I’m missing something.

      rgb

      • Presumably you meant “Σ ᵢ (T ᵢ₁ -)” for the 2nd term there, rgb. I agree that the two forms are equivalent, but perhaps the latter is a generalized one which is more easily applied to heterogeneous data, e.g., if each thermometer covers different surface areas in the two epochs.

  35. but we find absolutely no evidence that suggests that the Gulf Stream is slowing down
    It doesn’t matter whether the gulf stream is slowing these guys still get paid. The US government will pay for anything that supports their alarmist view, whether is true not doesn’t matter. I’m hoping a new administration will stop paying for this say anything propaganda machine.

  36. If this is a robust slowing signal (and with over-parameterized shaken and stirred data I doubt it), two things need to happen. 1) The study needs to be replicated to determine if the results are valid. 2) The signal needs to be demonstrated by other measures thus determining its reliability. However, since being granted global warming research money depends on producing results that adhere to the storyline, I doubt this study will ever be properly scrutinized.

    In addition, if the use of over-parameterized data in this study makes you throw up a little in your mouth, don’t then eat it for dessert when similar tactics are used to confirm some opposing pet theory about warming and cooling.

    • Here is the noise-to-signal of your dreams, Pamela. No over-parameterization here!

      (One year of college and he would have “Mr. Confidence Interval” tattooed all over himself.)

    • Pamela Gray,

      If this is a robust slowing signal (and with over-parameterized shaken and stirred data I doubt it), two things need to happen. 1) The study needs to be replicated to determine if the results are valid. 2) The signal needs to be demonstrated by other measures thus determining its reliability.

      Academic.

      However, since being granted global warming research money depends on producing results that adhere to the storyline, I doubt this study will ever be properly scrutinized.

      Speculation and well-poisoning. Supposed to be a no-no in these parts.

      In addition, if the use of over-parameterized data in this study makes you throw up a little in your mouth, don’t then eat it for dessert when similar tactics are used to confirm some opposing pet theory about warming and cooling.

      Slippery slope to just cause corruption, also supposed to be a no-no in these parts. I see a nice lecture about how to do good science in your comments, not much evidence of ability to walk the talk.

      • Brandon where are the error bars? If you want to legitimize Mann, help him produce error bars, and the rationale behind them. Real scientists either do this, or are soon caught out. “Climate Scientists,” not so much…

      • O’ contraire, I have walked the talk. I’ve been in the Ivory Tower. Not for long, but long enough. My published study was replicated. In fact I hoped it would be so made sure it could be. It was determined to be valid and reliable. I also know how grants are advertised. Many, if not most, grants are specific to a cause. The most money is still in the “Show connections to global warming” pile. Anybody can look that information up. The money available for research on global warning connections to human activity is much greater than the money available for natural weather pattern variation.

        So my next move is, show me yours. If you have not been through the rigor of published research, you are just a teetering toddler in this game.

      • Pamela Gray,

        The money available for research on global warning connections to human activity is much greater than the money available for natural weather pattern variation.

        Trenberth did suggest changing the null hypothesis. Did you agree with him?

        If you have not been through the rigor of published research, you are just a teetering toddler in this game.

        And you say you left the Ivory Tower. Let me put it to you this way; credentials do not impress me in and of themselves. Quality of arguments do. Trading on thinly evidenced, meager credentials alone … singularly unimpressive.

      • Michael Moon,

        None of those charts were from the referenced paper.

        Take it up with Anthony for the first one: UPDATE: I’ve added figures 5 and 6 from the Mann and Rahmstorf paper below.

        The second one is from Mann, Bradley and Hughes (1998): http://www.meteo.psu.edu/holocene/public_html/shared/articles/mbh98.pdf

        Figure 6b., p. 783 in the journal, p. 5 of the pdf.

        Mann’s wildly creative selective use of proxy “data,” the way he spliced thermometer data onto treemometer data, and invented a new, quite baseless application of Principal Component Analysis, are well-documented. You, sir, have drunk the Kool-Aid, good luck…

        Your original statement was: If you want to legitimize Mann, help him produce error bars, and the rationale behind them.

        I’ve shown you two figures from papers with Mann listed as author with error bars. You, sir, have erred, and no amount of trundling out other oft-regurgitated memes will make it any less obvious. Good luck trying.

    • Michael Moon,

      Brandon where are the error bars?

      Where are your eyes?

      If you want to legitimize Mann …

      If you want to legitimize Soon …

      Yeah. Best you just don’t go there.

      … help him produce error bars …

      No need, they’ve been around since 1998:

      … and the rationale behind them.

      Another swing and a miss. Strike three. Start about here:

      Methods
      Statistics.
      We use as our primary diagnostic of calibration and verification reconstructive skill the conventional ‘resolved variance’ statistic;

      Real scientists either do this, or are soon caught out. “Climate Scientists,” not so much…

      Real skeptics would at least bother to check that the error bars were indeed missing … and one would hope they could think of a more substantive argument to boot. Fake skeptics who only know how to argue, “If Mann’s name is on it, even if he isn’t the lead author, it must be wrong” …. not so much.

      • So zero change fits within your error bars (which are rather lacking in source and methods).

      • None of those charts were from the referenced paper. Mann’s wildly creative selective use of proxy “data,” the way he spliced thermometer data onto treemometer data, and invented a new, quite baseless application of Principal Component Analysis, are well-documented. You, sir, have drunk the Kool-Aid, good luck…

      • Real scientists pay attention to cautions related to spliced temperature reconstructions. The discontinuities are massive. Error bars more than likely underestimate the affect of records available to reconstruct temperatures. They also fail to consider the more highly variable Northern Hemisphere and because they do not consider this, they do not weight it as they should. This 2010 paper reminds us to interpret the hockey stick blade with caution. Funny how Mann banks on it over and over again, yet being slapped silly each and every time.

        From its conclusion:

        “Substantial parts of the Roman Warm Period, from the first to the third centuries, and the Medieval Warm Period, from the ninth to the thirteenth centuries, seem to have equalled [sic] or exceeded the AD 1961–1990 mean temperature level in the extra-tropical Northern Hemisphere. Since AD 1990, though, average temperatures in the extra-tropical Northern Hemisphere exceed those of any other warm decades the last two millennia, even the peak of the Medieval Warm Period, if we look at the instrumental temperature data spliced to the proxy reconstruction. However, this sharp rise in temperature compared to the magnitude of warmth in previous warm periods should be cautiously interpreted since it is not visible in the proxy reconstruction itself.”

        Meaning that when using the proxies that continue to move forward to the current state, the sudden rise in temperature is not visible in proxy reconstructions of current temperature. In other words, when splicing an apple to an orange, you cannot then call the entire thing an orange.

        http://scholar.google.com/scholar_url?url=http%3A%2F%2Fwww.agbjarn.blog.is%2Fusers%2Ffa%2Fagbjarn%2Ffiles%2Fljungquist-temp-reconstruction-2000-years.pdf&hl=en&sa=T&oi=gga&ct=gga&cd=8&ei=m_gRVay8G4G0qQHG34CwBw&scisig=AAGBfm3MFFNPm7HeA3LdV5jdJYMgHL6Yvg&nossl=1&ws=1600×747

      • At last, someone who can help us out with the irksome problem of how to calculate the confidence intervals in MBH98/99! Brandon, what’s the method? How did he do it?

      • Pamela Gray,

        This 2010 paper reminds us to interpret the hockey stick blade with caution.

        From its conclusion:

        “Substantial parts of the Roman Warm Period, from the first to the third centuries, and the Medieval Warm Period, from the ninth to the thirteenth centuries, seem to have equalled [sic] or exceeded the AD 1961–1990 mean temperature level in the extra-tropical Northern Hemisphere. Since AD 1990, though, average temperatures in the extra-tropical Northern Hemisphere exceed those of any other warm decades the last two millennia, even the peak of the Medieval Warm Period, if we look at the instrumental temperature data spliced to the proxy reconstruction. However, this sharp rise in temperature compared to the magnitude of warmth in previous warm periods should be cautiously interpreted since it is not visible in the proxy reconstruction itself.”

        Meaning that when using the proxies that continue to move forward to the current state, the sudden rise in temperature is not visible in proxy reconstructions of current temperature. In other words, when splicing an apple to an orange, you cannot then call the entire thing an orange.

        No, it says what it says, which you more or less faithfully interpreted in your lead comment: This 2010 paper reminds us to interpret the hockey stick blade with caution.

        Keep in mind that no proxy reconstruction would make sense without comparison to modern temperature records.

        Funny how Mann banks on it over and over again, yet being slapped silly each and every time.

        Although partly different data and methods have been used in our reconstruction than in Moberg et al. (2005) and Mann et al. (2008), the result is surprisingly similar. The inclusion of additional records would probably not substantially change the overall picture of the temperature variability. The major uncertainty lies in the magnitude of cooling during the Little Ice Age. It is, for several reasons discussed earlier, quite likely that our reconstruction underestimates the actual cooling.

        Funny how your reading skills are so very creative.

      • Real skeptics would notice that your last graph is conveniently B&W! Better not to let facts get in the way of a good story, no! You don’t want to draw to much attention to the artful splicing of “actual data” with that poxy resurrection (Proxy reconstruction). The whole issue of error becomes problematic when the proxy doesn’t match the record and can’t be spliced to it in any Intellectually honest way!

        But forget the proxy decline and smoothed splice, the pointy bit going vertical is more dramatic and has way less error associated with it. /sarc

        Hit that out of the park, big man!

  37. Thank you Anthony for a reasonable view on this topic. I went over to the Real Climate site to leave a comment and a question about the Mann Rahmstorf study and found out that they gatekeep every comment like vigilant gestapo commanders. I guess I’m not surprised. It will probably be buried in the Real Climate “Vault of Denier Thought.”

    • Ghandi,

      I went over to the Real Climate site to leave a comment and a question about the Mann Rahmstorf study and found out that they gatekeep every comment like vigilant gestapo commanders.

      I didn’t know the Gestapo blogged. I don’t know that all comments from every poster go to moderation by default, but I do know that all two of mine did.

      I guess I’m not surprised. It will probably be buried in the Real Climate “Vault of Denier Thought.”

      Don’t count your chickens. #16 here got through:

      Thomas O’Reilly says:
      23 Mar 2015 at 10:00 PM

      “Our recent study (Rahmstorf et al. 2015) attributes this to a weakening of the Gulf Stream System, which is apparently unique in the last thousand years.”

      “this indicates that climate models UNDERESTIMATE the weakening of the Atlantic circulation in response to global warming”

      “That this might happen as a result of global warming is discussed in the scientific community since the 1980s”

      It is 2015 now – 35 years later.

      What are you and the rest of the Climate Science community going to do about it now Stefan?

      More “research”? More “reanalysis”? Another “Paper”? Another “article” for Real Climate? An “AR6 IPPC Report” in a few years time?

      “Insanity: doing the same thing over and over again and expecting different results.” – Albert Einstein

      [Response: What is your suggestion what we should do as scientists, other than study the system to our best ability and communicate what we find? -stefan]

      Apparently, RC doesn’t have a vault for the banal and inane. Depending on what you wrote, the chances of your comment posting could be better than you think.

  38. ‘Thermohaline’ circulation notwithstanding, there is a MAJOR driver for oceanic currents that is independent of temperature ‘trends’ or atmospheric composition.
    Tides.
    They are driven by the orbital mechanics of the Earth-moon-sun system, and result in net clockwise circulation in the northern hemisphere and net anti-clockwise circulation in the southern hemisphere. The main source of the energy is the orbital energy of the moon around the earth. As the moon pulls the oceans around, stirring them, the moon itself is losing energy, which expands its orbit – about 3.8 cm/year.
    Temperature gradients and salinity gradients will not be able to stop this circulation of ocean currents.

  39. I really love the ‘burn, baby burn’ graphics. Even a scrambled egg yellow just won’t do. No, the most ominous and unattractive shade of superheated glowing cast iron orange is deemed necessary to represent the whole planet with the obligatory danger red shadings to indicate the spreading doom. And then, to provide a wink of contrast, a footnote to the supposed mythological scientific integrity of this birdcage liner paper and its conclusions we’re provided with a splash of anomalous blue below Greenland. Perhaps Rahmstorf and Mann need to have a conference call with John Holdren because where are the additional anomalous blues for the Polar Vortex’s that have been vomited into our ears?

    In the end I think the major question here is; ‘how will this affect John Kerry’s Eastern Seaboard yacht?’

    • really love the ‘burn, baby burn’ graphics. Even a scrambled egg yellow just won’t do. No, the most ominous and unattractive shade of superheated glowing cast iron orange is deemed necessary to represent the whole planet with the obligatory danger red shadings to indicate the spreading doom.

      Just like Satan’s city of Dis with its glowing, red-hot iron walls.

  40. 2 Geographers + 1 crappy model (excel) + 1 facked dataset (GISS) = “We have hit a critical de-salinization point.”

    IPCC notices central Africa “anomaly” and jumps up shouting, “There IT IS THERE IT IS, Africa is sinking, the world will implode because of Global Human Warming!”

    Ha ha

  41. The funny thing is that the mechanism they are describing is what they would usually call a “negative feedback” to warming that would act to reduce the magnitude of the warming.

    Now, it is possible in theory for a huge negative feedback to overshoot the mark, but when it is very difficult to determine whether the effect is there at all, we are very, very far from that point.

    I say this as someone who has made his living in feedback control systems for 30 years now.

  42. I took some time on a facebook discussion page describing to Box how it requires negative North Atlantic Oscillation conditions to increase warming of the AMO and Arctic, and how increased forcing of the climate increases positive NAO. Evidently facts get in the way when ones only motive is to scare everyone including his 3 year old daughter with yarns that we are responsible, and how “eventually the dragon becomes pissed off enough to trash the place.”

    http://motherboard.vice.com/read/if-we-release-a-small-fraction-of-arctic-carbon-were-fucked-climatologist?

    • Seeing the extremes of rabid alarmism that Box exhibits, I highly suspected that he would be into astronomy, like Hansen, deGrasse Tyson, John Cook, and even Brain May. I do have a Jungian type theory for this association, those familiar with my take on climate change would see the funny side of it, however tragic it is.

  43. When I consider how hard the climate of doom hypesters work the phrase, “lying liars and the lies the [liars] tell” comes to mind for some reason.

    • Toss in a liebaby here and there, just for emphasis: “Lying liebaby liars…yadda yadda yadda.)

  44. Anthony,

    As WUWT reported on a peer reviewed paper last year, H. Thomas Rossby says: URI oceanographer refutes claims that climate change is slowing pace of Gulf Stream saying in a paper published in Geophysical Research Letters: “The ADCP measures currents at very high accuracy, and so through the repeat measurements we take year after year, we have a very powerful tool by which to monitor the strength of the current,” said Rossby. “There are variations of the current over time that are natural — and yes, we need to understand these better — but we find absolutely no evidence that suggests that the Gulf Stream is slowing down.”

    Check.

    Weblink to the article: http://dx.doi.org/10.1038/nclimate2554

    Abstract

    Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change. Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change.

    Gulf Stream != AMOC. Learn how to read.

    • “Gulf Stream != AMOC. Learn how to read.”

      So we have “absolutely no evidence that suggests that the Gulf Stream is slowing down”, but we have changes in the AMOC. For all you know the gulf stream may speed up during low AMOC events.
      Leaving aside “possible” changes in the AMOC and examining the real changes, they are linked to negative NAO episodes:
      http://www.rapid.ac.uk/

      • Ulric Lyons,

        So we have “absolutely no evidence that suggests that the Gulf Stream is slowing down”, but we have changes in the AMOC.

        I don’t see an inherent conflict. The GS is a surface-driven phenomenon, the AMOC is a thermohaline circulation. That they share some common geography suggests a linkage between the two — and literature has done so [1] — but doesn’t necessarily demand that they march in lockstep over all frames of reference. I think it takes more than two papers to figure this out, and certainly a paper on one shouldn’t be expected to falisify the other. They could BOTH be completely wrong, after all.

        For all you know the gulf stream may speed up during low AMOC events.

        Correct, not least because I wouldn’t claim to know very much about either phenomenon.

        Leaving aside “possible” changes in the AMOC and examining the real changes, they are linked to negative NAO episodes:
        http://www.rapid.ac.uk/

        That splash page does not specifically mention NAO. Not that it matters much; NAO is a pressure differential index so until you explain what drives NAO you’ve only created another chicken-egg problem.

        ——————

        [1] See:

        Joyce and Zhang (2010), On the Path of the Gulf Stream and the Atlantic Meridional Overturning Circulation: http://journals.ametsoc.org/doi/full/10.1175/2010JCLI3310.1

        Ezer (2015), Detecting changes in the transport of the Gulf Stream and the Atlantic overturning circulation from coastal sea level data: The extreme decline in 2009–2010 and estimated variations for 1935–2012: http://www.ccpo.odu.edu/~tezer/PAPERS/2015_GPC_AMOC_SL.pdf

      • David A: That would explain it.

        Ulric Lyons: I posted a substantive reply to you which went to moderation and has now evaporated. I suspect WordPress issues.

    • Brandon said:
      “That splash page does not specifically mention NAO. Not that it matters much; NAO is a pressure differential index so until you explain what drives NAO you’ve only created another chicken-egg problem.”

      True, it does not mention the NAO, it should have done really as the correlation is so strong at the noise level. Revealing the correlation does not rely upon an explanation of the cause of NAO variability in any way, and patently, negative NAO is not increased by an increase in forcing of the climate. So it’s the wrong sign to be associated with AGW.
      In fact the RAPID article baits the chicken-egg problem by suggesting a link between low AMOC events and cold winters, while failing to mention the tight negative NAO correlation. While from my own experience of producing long range solar based forecasts for NAO/AO variability at finer than weekly resolution since 2008, the attribution is crystal clear.

      • Ulric Lyons,

        True, it does not mention the NAO, it should have done really as the correlation is so strong at the noise level.

        Um. You wrote: Leaving aside “possible” changes in the AMOC and examining the real changes, they are linked to negative NAO episodes:
        http://www.rapid.ac.uk/

        ???

        Revealing the correlation does not rely upon an explanation of the cause of NAO variability in any way, and patently, negative NAO is not increased by an increase in forcing of the climate.

        This entire discussion is concerned with causality. Explanations are required. I’d settle for some citations.

        In fact the RAPID article baits the chicken-egg problem by suggesting a link between low AMOC events and cold winters, while failing to mention the tight negative NAO correlation.

        NAO is an atmospheric surface pressure index. AMOC is a subsurface thermohaline-driven ocean current. Which is the more likely to influence the other?

        While from my own experience of producing long range solar based forecasts for NAO/AO variability at finer than weekly resolution since 2008, the attribution is crystal clear.

        Weekly? I’m talking about climate, you’re talking about weather. Solar fluctuation:

        CO2 fluctuation:

        Bit of a difference in the short vs. long term fluctuations. Even if we zoom out a bit:

        Or maybe ESPECIALLY when we zoom out a bit:

      • D.S said:
        “NAO is an atmospheric surface pressure index. AMOC is a subsurface thermohaline-driven ocean current. Which is the more likely to influence the other?”

        Atmospheric circulation variability drives all the oceanic modes, typically through Ekman transport and drifting rates.

      • D.S. said:
        “Weekly? I’m talking about climate, you’re talking about weather.”

        There would be no trend without variations in the the noise. Scrutinise the AMOC data, it all happens at the scale of weather. That adds up to climate over time. Note what the sign of correlation is at the noise level, so as not to to get your whole theory the complete reverse of reality.

  45. The data showing they have no clue what they are talking about.

    It supports a solar/ AMOC correlation. They have no data to show it is related to AGW theory. This is similar to their nonsense that Low Arctic Sea Ice values equates to a more meridional jet stream pattern.

    They are full of it.

    • Salvatore Del Prete,

      The data showing they have no clue what they are talking about. It supports a solar/ AMOC correlation.

      From 1025-1275, 10BE makes a big bowl. The blue subpolar gyre minus NH anomaly doesn’t budge. From 1900-present, the blue curve falls off the cliff and …

      Look Ma! No Sun!

      … the 10BE curve disappears.

      They have no data to show it is related to AGW theory.

      You have no data showing it is related to the solar constant since:

      1) The correlation is curiously AWOL for 250 years early in the record and which you’ve not explained.
      2) The proxy reconstruction for solar constant you shows STOPS 100 years before the end of the plot.

      Try your hand with this one:

      Data for that one and others here: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/climate_forcing/solar_variability/

      They are full of it.

      Irony. Well, since you’re a fan of correlations:

      I typically find that late Holocene reconstructions don’t make sense unless I also include Milankovitch orbital forcing. Berger (1978) is a big help: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/climate_forcing/orbital_variations/berger_insolation/

      Temps lag orbital forcing significantly on geologic timescales, but for this exercise there isn’t much need to account for that.

      • Brandon, Steinhilber’s data does not correlate all that well to the record of historical Grand Minima of solar activity. It shows decreases in some cases but they do not look like Grand Minima events.

        A list of historical Grand minima of solar activity[27] includes also Grand minima ca. 690 AD, 360 BC, 770 BC, 1390 BC, 2860 BC, 3340 BC, 3500 BC, 3630 BC, 3940 BC, 4230 BC, 4330 BC, 5260 BC, 5460 BC, 5620 BC, 5710 BC, 5990 BC, 6220 BC, 6400 BC, 7040 BC, 7310 BC, 7520 BC, 8220 BC, 9170 BC.

      • Salvatore Del Prete,

        Brandon, Steinhilber’s data does not correlate all that well to the record of historical Grand Minima of solar activity.

        All that tells me is that one proxy reconstruction doesn’t always agree with all others. Which is business as usual, and to be expected since this stuff isn’t easy. Que all the usual cationary tales about basing conclusions on the results of a single study. When studying a complex system using sparse and uncertain data, convergence of multiple lines of evidence is required for making reasonable conclusions.

        You’ve avoided answering what happens to TSI after 1900 to present, and completely ducked the CO2 activity during that interval, which is the MOST RELEVANT part of this discussion. Why.

      • Brandon after 1900 TSI increased in response to strong solar activity(the modern maximum) and the N. Atlantic Gyre was more intense due to strong solar activity meaning if taken out of the mix N.H. temperatures would have shown a warm anomaly which is consistent with a +ao/+nao atmospheric circulation at times of high solar activity which equates to a cold Arctic ,warm Lower Latitude regime set up, along with a more intense N. Atlantic Gyre. Cold air being locked into high latitudes when a +AO/+NOA set up is in play.

        CO2 has no correlation to sea surface temperatures or the NAO/AO.

        It is the visible light from the sun and long wave UV light, that impact ocean temperatures since they penetrate the ocean to great depths in contrast to IR radiation which maybe penetrates the ocean surface to the tune of 1mm.

  46. Climate science urban legends are perpetuated by disingenuous scientists (who hide and/or suppress observational evidence and analysis that does not support CAGW) and by the fact that climate scientists do not understand (urban legends fill the theoretical void) what causes (there is unknown massive forcing function that causes abrupt climate change, there is no amplification mechanism that magically appears when there is abrupt climate change and then hides when there is not) the massive abrupt climate changes that cyclically initiate and terminate interglacial periods (for example the Younger Dryas abrupt cooling event or the 8200 BP cooling event.)

    Realclimate blog contributors Michael Mann and Stefan Rahmstorf are disingenuously implying that a complete stoppage of the North Atlantic drift current would have a great impact on European winters by not explicitly stating the following fact which is known to all people who are knowledgeable about this issue.

    It is the earth-climate equivalent of an urban legend that Europe’s mild winters are due to the North Atlantic Drift current which is referred by some incorrectly as the Gulf stream. The reason why European winters are 10 to 15 degrees Celsius warmer is primarily due to the fact that the prevailing winds are from the west. Each summer the North Atlantic ocean warms due to the increase insolation in the summer, as compared to the winter. The heat energy from summer warming is released in the winter and as the prevailing winds are from the west that released heat warms Europe rather than the east coast of North America. Basic model analysis (done in the 1980 and then repeated in 2002) indicates the release of the heat from the summer heating of the North Atlantic ocean is a factor of two more than the heat released by the North Atlantic drift current, therefore a complete stoppage of the North Atlantic drift current would only result in winter cooling of Europe of only a few degrees Celsius.

    The same phenomena where the ocean warms one side of a continent as the prevailing winds are from the west occurs in North America. The average January temperature of Seattle 47 Degrees North is (6C) as compared to the average January temperature of Boston 42 Degrees North or (-1.5C).

    http://www.americanscientist.org/issues/id.999,y.0,no.,content.true,page.1,css.print/issue.aspx

    The Source of Europe’s Mild Climate
    The notion that the Gulf Stream is responsible for keeping Europe anomalously warm turns out to be a myth.

    If you grow up in England, as I did, a few items of unquestioned wisdom are passed down to you from the preceding generation. Along with stories of a plucky island race with a glorious past and the benefits of drinking unbelievable quantities of milky tea, you will be told that England is blessed with its pleasant climate courtesy of the Gulf Stream, that huge current of warm water that flows northeast across the Atlantic from its source in the Gulf of Mexico. That the Gulf Stream is responsible for Europe’s mild winters is widely known and accepted, but, as I will show, it is nothing more than the earth-science equivalent of an urban legend.

    The Longevity of a Legend
    When Battisti and I had finished our study of the influence of the Gulf Stream, we were left with a certain sense of deflation: Pretty much everything we had found could have been concluded on the basis of results that were already available. Ngar-Cheung Lau of the National Atmospheric and Oceanic Administration’s Geophysical Fluid Dynamics Laboratory (GFDL) and Princeton University had published in 1979 an observational study in which he quantitatively demonstrated the warming and cooling effects that large-scale waves in the atmosphere had in Europe and eastern North America, respectively. In the 1980s, atmosphere modelers such as Brian J. Hoskins and Paul J. Valdes at the University of Reading in England and Isaac M. Held and Sumant Nigam at GFDL had shown how such stationary waves, including those forced by mountains, warm western Europe. In the late 1980s, two other GFDL researchers, Syukuro Manabe and Ronald J. Stouffer, had used a coupled ocean-atmosphere climate model to determine the climate impacts of an imposed shutdown of the North Atlantic thermohaline circulation. Their modeled climate cooled by a few degrees on both sides of the Atlantic and left the much larger difference in temperature across the ocean unchanged. Other published model experiments went on to show the same thing. Further, the distinction between maritime and continental climates had been a standard of climatology for decades, even centuries. What is more, by the late 1990s satellite data, and analyses of numerical models into which those data had been assimilated as part of the weather-forecasting process, had shown that in mid-latitudes the poleward transport of heat by the atmosphere exceeds that by the ocean several-fold.

    http://www.atmos.washington.edu/~david/Gulf.pdf

    Is the Gulf Stream responsible for Europe’s mild winters?
    By R. SEAGER, D. S. BATTISTI, J. YIN, N. GORDON, N. NAIK, A. C. CLEMENT and M. A. CANE (OCTOBER 2002)

    It is widely believed by scientists and lay people alike that the transport of warm water north in the Gulf Stream and North Atlantic Drift, and its release to the atmosphere, is a major reason why western Europe’s winters are so much milder (as much as 15–20 degC) than those of eastern North America (Fig. 1). The idea appears to have been popularized by M. F. Maury in his book The physical geography of the sea and its meteorology (1855) which went through many printings in the United States and the British Isles and was translated into three languages.

    In summary, the east–west asymmetry of winter climates on the seaboards of the North Atlantic is created by north-westerly advection over eastern North America and by zonal advection into Europe. The Pacific Ocean has an analogous arrangement with meridional advection being an especially strong cooling over Asia. Since western Europe is indeed warmed by westerly advection off the Atlantic, we next assess how the surface fluxes over the Atlantic are maintained.

    In conclusion, while OHT warms winters on both sides of the North Atlantic Ocean by a few deg Celsius (William: Basic simulation indicates a complete stoppage of the North Atlantic drift current would result in cooling of only a few degrees Celsius not 15 to 20 degree Celsius), the much larger temperature difference across the ocean, and that between the maritime areas of north-western Europe and western North America, are explained by the interaction between the atmospheric circulation and seasonal storage and release of heat by the ocean. Stationary waves greatly strengthen the temperature contrast across the North Atlantic and are themselves heavily influenced by the net effect of orography. In contrast, transport of heat by the ocean has a minor influence on the wintertime zonal asymmetries of temperature. Even in the zonal mean, OHT has a small effect compared to those of seasonal heat storage and release by the ocean and atmospheric heat transport. In retrospect these conclusions may seem obvious, but we are unaware of any published explanation of why winters in western Europe are mild that does not invoke poleward heat transport by the ocean as an important influence that augments its maritime climate.

    Comment: I have made the same comment as the above, multiple times at Realclimate. I provided the same peer reviewed paper link to a paper published in 2002 which are supported by a paper that was published in 1980s (i.e. The assertion that the a complete stoppage of the North Atlantic drift current would not have result in European winters being as cold as the winters on the east coast of the US is not controversial and should be understood by any competent physical scientist.) at the blog Realclimate in response to incorrect statements by Mann, Rahmstorf, and Schmidt in connection to the cause of Younger Dryas abrupt cooling event. The cause of the Younger Dryas abrupt cooling or the 8200 BP abrupt cooling could not be the stoppage of the North Atlantic drift current (see below for the reason why) and it is a fact that ‘stoppage’/slow down of the North Atlantic drift current occurred 1000 years before the Younger Dryas.

    • @ William Astley, Thank you when I went to school (and a very strict one at that) in the 60’s our teachers in geography., history and physics (those were still taught in those days at that level) all had a very simple explanation, I do not know if it still stands, They called a “Sea climate” and a “Land climate” a little simple these days perhaps but to us as 12-13 year olds it made sense then as as it does now.

      • BTW those three guys including our German language and art teachers made the classroom come alive. I remember every single one of them vividly. It is a sad thing to see our education system give everyone a “medal” these days!

  47. It seems that the most accurate part of the article is the disclaimer:

    “AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.”

  48. Ha Ha ha HaaaaaaaaH!
    For Mann he is a Moron, la, la, la, lah! etc. etc.

    That’s how much I care about Mann’s latest BS.

  49. They claim (in Figure 1 from their paper) that this cold spot south of Greenland is caused by meltwater from Greenland…

    They claimed Greenland was melting all those years it was a warm spot too…..

  50. My question to them based on if what they say below is correct, and their theory of high latitude cooling as a result is correct due to a slow down in the AMOC, is why then is the AMO in a warm phase if the AMOC is slowing down? According to your theory you suggest a cooling of the high latitudes should result due to a slow down of the AMOC, if so how does the AMO not only attain a warm phase and stay in that warm phase as the AMOC slows down , promoting high latitude warmth, when a slow down of the AMOC according to what you suggest should promote the opposite ?

    The melting Greenland ice sheet is likely disturbing the circulation”

    The Atlantic overturning is driven by differences in the density of the ocean water. From the south, the warm and hence lighter water flows northwards, where the cold and thus heavier water sinks to deeper ocean layers and flows southwards. “Now freshwater coming off the melting Greenland ice sheet is likely disturbing the circulation,” says Jason Box of the Geological Survey of Denmark and Greenland. The freshwater is diluting the ocean water. Less saline water is less dense and has therefore less tendency to sink into the deep. “So the human-caused mass loss of the Greenland ice sheet appears to be slowing down the Atlantic overturning – and this effect might increase if temperatures are allowed to rise further,” explains Box.

    The observed cooling in the North Atlantic, just south of Greenland.

    From Ulric

    From the Abstract:
    “Using a multi-proxy temperature reconstruction for the AMOC index suggests that the AMOC weakness after 1975 is an unprecedented event in the past millennium”

    Given that low AMOC events are inextricably linked to negative North Atlantic Oscillation episodes, and that increased GHG’s should increase positive NAO, they have shot themselves in the foot.

  51. Steady rise in accumulation based on Box and Colgan. Thankfully, for now, there has been a corresponding rise in run off and calving at the margins. For now …. :0

  52. From Ulric, which I think gives an explanation to my question. Ulric, any commentary to add would be appreciated.

    So if the gulf stream is not slowing, where does the warm flow go during a slow AMOC event?
    It accumulates in the north Atlantic and spills into the Arctic instead of overturning.

    Low AMOC events tightly correlate with negative NAO episodes, e.g. early summer 2007 and mid summer 2012, and cold winter months in 2010 and March 2013:
    http://www.rapid.ac.uk/

    IPCC models predict increasingly positive NAO with increased GHG’s.

    Seas south of Greenland warm up from these negative NAO episodes:
    http://weather.unisys.com/archive/sst/

    Demonstrate a solar forcing of the NAO, and that would tie the whole thing up.

    • Yes, the IPCC models are correct in saying that increased GHG forcing will increase positive NAO, but then one has to account for why the NAO has been shifting negative since 1995.

      Positive NAO in the last couple of years follows the pattern of AMO cooling at sunspot maxima when the AMO is in its warm mode. Hence the recent changes in sea ice and Greenland. This will be followed by a strong renewed warming of the AMO, moving out of phase with solar cycles, as it does in its warm mode, and the associated loss of sea ice and warming in Greenland.
      http://www.woodfortrees.org/plot/esrl-amo/from:1880/mean:13/plot/sidc-ssn/from:1880/normalise

    • ULRIC how about this sequence- Maximum Solar Activity -amo cooling,+nao/+ao, +amoc, Europe warm, Arctic cold, general N.H. sea surface temperature as Paul indicates warm.

      versus

      Minimum Solar Activity -amo warming,-nao/-ao, -amoc ,Europe cold, Arctic warm, general N.H. sea surface temperature as Paul indicates cool.

      Hold on – are we saying that the AMO drives the sun?
      Or are we saying that every cyclical phenomenon on earth is driven by a corresponding cycle somewhere in the sun?
      As below, so above?

      • Yes, the strong solar wind in the 1970’s driving it colder, and the decline since the mid 1990’s causing the AMO and Arctic to warm up. This negative feedback has raised the global average sea surface temperature, and raised average land temperatures even faster because of warm AMO driven reductions in regional continental precipitation.

    • But you can’t expect people like mr mann to admit that we’re entering a LIA, and accept that it’s due to solar activity. They have to wriggle out of it, do they not? I saw this one coming yonks ago, no surprises here.

      • Problem with Mr Mann isn’t that he has a hard time accepting reality. Problem for Mr Mann is that he show he lack not only credibility that comes by using Theories of Science. He also lack all needed skills a real “leader” has to have. Such as listning, reflecting but above all the skill to lift people up not critizes those who don’t agree with him….

        I myself saw this coming in 2008. Klimatfrågan….. och över alltihopa lyser Moder sol, Norah4you 2008/07/25 unfortunatly not translated from Swedish to English …..

  53. Oh No!! more mann made gorebull warming……..”it is way worse than we thought….. quick everyone stop breathing!!! Oh wait give over your wallets and valuables first!” Gadzooks it is models models models treated like empirical evidence. what a bunch of “maroons” to quote Bugs.

    Cheers!

    Joe

  54. Low AMOC events tightly correlate with negative NAO episodes, e.g. early summer 2007 and mid summer 2012, and cold winter months in 2010 and March 2013:
    http://www.rapid.ac.uk/

    Ulric says above. I might add a -AO is also present with a -NAO which equates to a warm Arctic, while the lower latitudes experience a cold winter.

    While all this is going on the AMO is in it’s warm phase while solar activity is on the decline.

      • Not with Arctic sea ice, the range between maximum and minimum extent has reduced considerably in the last few years. Got any good examples of what has become ” more highly variable” in very recent years then?

  55. So. I have some basic questions. Yes, the North Atlantic sea is less salty than other locations of the Atlantic because of fresh water dilution from melting ice. However, sea ice comes from the sea and then returns to the sea, meaning that is a closed loop with likely decadal variations due to waxing and waning of sea ice cover. To be sure, the entire water cycle is a closed cycle but lets look at less than millennial scales. The only addition for this trend of fresh water dilution must come from an increasing source of melt water from land ice or increasing river discharge. For the sake of argument, lets say that both are happening and the sea surface salinity in the NA region is getting diluted.

    Places along the Gulf Stream have varying amounts of evaporation and less than/more than salinity because of precipitation and evaporation. Fresh water evaporates faster than salty water, plus it sits on top of the salty water, even though temps may be the same, salt water being heavier than fresh water. So the question is, is the North Atlantic undergoing evaporation? And is that evaporation faster due to the proposed Greenland land ice sourced freshwater sitting on top? Given this mind experiment, I am thinking that there is not enough change outside the normal range of the North Atlantic salinity to slow down a MASSIVE ocean current nor its final destination and action at the overturning location near/in the North Atlantic Arctic.

    http://www.srh.noaa.gov/jetstream/ocean/seawater.htm

    • The North Atlantic also has the mighty St. Lawrence and the mighty Rhine pouring into it. Especially the former is still draining off the water from the Great Melt.

  56. Isn’t the slowing down of the Gulf stream practically a joke among oceanographers? I remember listening to a conference panel (over the internet, I don’t attend climate conferences) where the panelists almost felt somewhat ashamed that this subject ever got so much traction in the media and concluded (to kill the subject) that what would be required to make it stop was that the “wind stops blowing and the earth stops rotating”.
    Also, wouldn’t a slowdown of the GS imply a cooling of the north pole, which would probable act as a significant negative feedback? Isn’t the Younger Dryas and example of this?

  57. Work from Paul Vaughn. Can you reconcile what you have said with this? I say perhaps because the AMO is but a part of the N.H sea surface temperature picture, and it would be superimposed upon the back ground of the general sea surface temperatures. I think you had agreed over time ocean heat content would be lost if prolonged solar minimum conditions existed and I think this is how Paul’s research and your research can be reconciled?

    I would be interested in your commentary on Paul’s research and if it ties into yours.

    • “Can you reconcile what you have said with this?”

      Not in the slightest, as he is trying to wiggle match forcings directly to sea surface temperatures, The 1970’s cooling was oceanic negative feedbacks to stronger solar wind states, not fewer sunspots.

    • I guess if Lief says it’s not the Sun, then it can’t be the Sun. Pam’s guru hath spoken……

      • All solar triggers so far discussed on this blog requires the use of an amplifier, much like CO2 warming is connected to a water vapor amplifier. Which is better at promoting their pet amplifier? Now that is a true neck and neck race because neither do a good job. However, though I do not agree with human influenced warming, the CO2 camp does have a slight lead by saying that the oceans are warming thus should be evaporating water into the air. At least the physics is there. Too bad for the warmists camp’s bottom line that observations don’t confirm it.

      • I agree with Pamela here. The solar enthusiasts make the same mistake as the CO2 worshipers. That is, to regard the climate atmosphere-ocean system as passive. To one group, every tiniest wiggle up or down can only be CO2. To the other, it can only be the sun. This is a huge mistake. The system is complex with chaotic-nonlinear dynamics. It is full of internal cycles.

        Do we really believe that if the sun’s tiny oscillations suddenly stopped, and if the tiny fraction of CO2 in the atmosphere stopped increasing or decreasing, that climate would immediately become static?

        This is all chaos-denial.

  58. ULRIC how about this sequence- Maximum Solar Activity -amo cooling,+nao/+ao, +amoc, Europe warm, Arctic cold, general N.H. sea surface temperature as Paul indicates warm.

    versus

    Minimum Solar Activity -amo warming,-nao/-ao, -amoc ,Europe cold, Arctic warm, general N.H. sea surface temperature as Paul indicates cool.

  59. When is Penn State going to fire Mann?? Mann is making Penn State look even more foolish than the Joe Paterno scandal !!!

  60. http://hockeyschtick.blogspot.com/2010/01/climate-modeling-ocean-oscillations.html

    Ulric , so what you are saying is that you think this study I am sending (above)and the research I just sent that Paul has done showing a strong correlation between sea surface temperatures and sunspot Integral/Deceleration you can not reconcile against your conclusions.

    I think you are both correct and my reasoning is the phase of the AMO does not have to necessarily translate into correlating with the entire N.H. sea surface temperature anomaly, which includes an area in Paul’s research extending from 9N-90N Latitude.

    Look at the post Mar.24 at 11:07am.

    That data you conclude is wrong? As well as the study I sent with this post? Correct? Thanks.

  61. Just noticed your reply Ulric.

    My thought which you do not agree with is I think both of you can be partially correct.

    “Can you reconcile what you have said with this?”

    Not in the slightest, as he is trying to wiggle match forcings directly to sea surface temperatures, The 1970’s cooling was oceanic negative feedbacks to stronger solar wind states, not fewer sunspots

  62. I find it interesting that they note “…that the second cooling patch in central Africa is in a region of poor data coverage and may be an artefact of data inhomogeneities.” Yet somehow that cooling patch south of Greenland is free of such problems in the same GISS dataset. Go figure.

    8-)
    In other words, “We haven’t adjusted the central Africa data to fit the AGW meme (yet) but we can make the Greenland data fit.”

  63. Lots of apples and pears here

    However, even more puzzling, when you look at the Box and Colgan (2010) Figure 5 from their paper (free PDF here) the mass balance loss and accumulation shows no such “hockey stick” shape.

    This is because one is cumulative and the other is not.

    Also in the Rossby article it is clearly stated that their measurements are not measurements of the (A)MOC.

    Lastly, we should note that it is not sufficient to consider layer transport near the surface as a proxy for the MOC.

    They also acknowledge a discrepancy between their measurements and sea level measurements and that measurements of a decrease in MOC are consistend with sea level measurements.

    Using the AVISO altimetric data set, Ezer et al. [2013] find that sea level difference across the Gulf Stream is decreasing at an accelerated rate since 2004. Inspection of their Figure 5 (panel of remaining trend) yields >0.1 m over the 1993–2011 interval, a factor 3 greater than our direct estimate. While we cannot determine the specific reasons for this discrepancy (e.g., exact location and analysis methods) [Ezer et al., 2013], we show here the difficulty in estimating Gulf Stream transport change from local altimetric analysis due to the continual shifting of the narrow swift Gulf Stream over a continuum of spatial and temporal scales.

    For example, McCarthy et al. [2012] note a 30% reduction in the MOC from early 2009 to mid-2010, a very large signal that does not appear in the Oleander surface transport. On the other hand, it does show up in sea level difference between Bermuda and the U. S. East Coast [Ezer, 2013]. Profiling currents to and across the main thermocline would enable us to distinguish between surface and internal modes of variability and study their characteristics more effectively than we can today.

    So yes, there is definitely a lot of guesstimating in the Rahmstorf/Mann article, and this has to be made very clear. However, as far as I can tell there is no clear contradiction with the works of Rossby or Box and Colgan.

  64. I was reading where the turnover cycle is 1500 years. Now can anyone explain how they know it’s slowing in the space of 30 years?

    • 4TimesAYear:

      Note in the comment just above yours:

      Also in the Rossby article it is clearly stated that their measurements are not measurements of the (A)MOC.

      Lastly, we should note that it is not sufficient to consider layer transport near the surface as a proxy for the MOC.

      They are not actually measuring the AMOC. Looks like they stick a float in the surface and call it good enough… so measuring a surface layer velocity and attempting to use that to indicate and volume at depth… Uh, right….

  65. Maybe off topic a bit.
    But even though this post doesn’t display quite right and the “make a comment section” doesn’t display, it is worth a read. (I particularly like Hansen’s quote put on the charts)

  66. There’s real combat…and there are video games. There’s real ocean circulation…and there are computer models.

  67. The consensus view from IPCC AR5, WG1, Chapter 3

    In summary, measurements of the AMOC and of circulation elements contributing to it, at various latitudes and covering different time periods, agree that the range of inter-annual variability is 5 Sv (Figure 3.11b). These estimates do not have trends, in either the subtropical or the subpolar gyre. However, the observational record of AMOC variability is short, and there is insufficient evidence to support a finding of change in the transport of the AMOC.

  68. There is evidence that before an ice age or mini, there is a warmer climate. (An interglacial)
    It is thought that sea ice and land ice did melt and the fresh water drives the salt water deeper and could divert the Gulf Stream. But – its got nothing to do with CO2 levels. There is evidence ash from volcanoes is still embedded in glaciers from thousands of years ago.
    But the real culprit is our sun, maybe someone could plot our future orbit to warn us of an impending cold period. Or measure the amount of cosmic rays hitting our atmosphere that help create clouds. Sun spots divert those sub atomic particles from melding with water vapor molecules. Oh, and predict huge asteroid impacts and mega volcanic eruptions. Get your crystal balls out Mr Mann.

  69. Please all of you, I ask simple question, can all of you start your comment with …. @ so and so. the reply thingy does not work for me. It is a simple thing to do and add a time reference as well it really helps us.

    [???? Put the person to whom you are replying at the start of your comment, add (in blockquotes) what phrase you wish to append or comment on, then get on with your comment. .mod]

    • @ the mod,[???? Put the person to whom you are replying at the start of your comment, add (in blockquotes) what phrase you wish to append or comment on, then get on with your comment. .mod]
      I try, I wish all did that’s what I meant..

  70. But when the media reports on scientific studies ,suddenly the fudge words disappear.
    Then its reported as conclusive gospel,no “ifs” “coulds” or “possibles”.

    “rh
    March 24, 2015 at 5:41 am

    How does one scare the public without technically committing fraud?
    Weasel words, that’s how.
    “could impact marine ecosystems”
    “could have major negative effects”
    “could happen as early as within this century”
    “could contribute to further weakening ”
    “If the circulation weakens”
    “If the slowdown of the Atlantic overturning continues”
    “if temperatures are allowed to rise ”
    “overturning circulation might be to blame”
    “this effect might increase”
    “impacts might be substantial”
    “possible contribution of the melting”
    “Possible changes in Atlantic meridional overturning circulation (AMOC)”
    “possible tipping element in the Earth System”
    “global warming, is a possible major contributor””

    • MojoMojo

      These findings should be submitted to the JCSM – Journal of Catastrophe in the Subjunctive Mood
      (if, maybe, I wish, could, possibly, may, projected etc…)

  71. “…Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research, expert for thermohaline ocean circulation and its effects on climate…”

    Do tell…

    There sure is a lot of grandeur exaggeration amongst the CAGW devotees. Must do wonders for the egos of their employees…

  72. As Joe Bastardi points out,
    this slowing of the gulf stream is completely normal and expected
    as the AMO starts its downturn.
    This will lead to continued Arctic sea ice recovery.

  73. ‘”Now freshwater coming off the melting Greenland ice sheet is likely disturbing the circulation,” says Jason Box of the Geological Survey of Denmark and Greenland.’

    I’m sure glad it never rains over the ocean.

  74. Why does “Icouldnthelpit” keep posting (snip)?

    [he’s been told that his posts are on hold for 24 hours, because he violated site policy yesterday by labeled people here as “deniers”. He keeps posting anyway -mod]

  75. Says Mann: “Common climate models are underestimating the change we’re facing, ”

    Or, in other more familiar words, “It’s even worse than we thought”.

    One hardly knows whether to yawn, or point and laugh.

  76. Okay, my math isn’t so good, but …. what does this mean?

    In the past 110 years (of the article) 13,000km3 of ADDITIONAL fresh water have been added to the NAtlantic. If melting only occurs during 180 days per year, that is 0.66km3 of MORE fresh water per day. If this water spreads out over only 500km by 500km, that means 2.6mm/day more fresh water. And the oceanic spread is more than 500km X 500 km …

    Does this seem like enough to do anything?

    It is not the cumulative that does anything, it is the daily input of (negative) energy that does something, as each day the Gulf Stream is regenerated from the energy input from Africa and the tropical Atlantic.

  77. But, but, but — a slowing of the Gulf Stream and regional cooling because of increased Greenland meltwater would be negative feedback!

  78. Dear Anthony
    Next to the fact that cumulative data tend to show “hockey-stick” like shape I see another flaw in your posting.
    You state “And then there’s this other problem; Greenland’s ice mass seems to be on the increase so far this year and above the 1990-2011 mean”.

    You try to prove this with two graphs from the DMI Website. Nice try; but since you have been on the website from DMI why did you not see their statement (on the same page) on the annual ice loss of Greenland of 200Gt annually over the last decade? SMB is not the total Ice mass balance.
    So the other problem is not the ice mass increase but the elective reading on your side.

  79. Rather than a shut down of the gulf stream, I believe that it is changes in the gulf stream that might account for two remarkably warming phases in the region – from 1910 to 1940 and from 1976 to 2006. When I looked at Reykjavik and two locations on Svarlbard (Svarlbard Airport and the earlier Isfjord Radio), I noted that from trough to peak in the raw data was similar. On Svarlbard if anything the warming was more rapid and of greater magnitude than the more recent warming.

    The adjusted data pretty much smothers the early twentieth century warming period. Mann and Ramsdorf have used homogenized data that appears to have a bias towards Mann-made global warming. This is not a deliberate attempt to deceive, but – like with the MWP – any data that indicates large natural temperature fluctuations must be distorted, so is largely eliminated. Eminent climate scientists have knowledge derived from climate models that is prior to real world data.
    The full account is at http://manicbeancounter.com/2015/03/03/realclimates-mis-directions-on-arctic-temperatures/

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