Whats up with the Atlantic?

by Judith Curry

The Washington Post has this dramatic headline:  Global warming is now slowing down the circulation of the ocean with potentially dire consequences.

A new paper has been published that has the media talking about The Day After Tomorrow [link].  What is this new paper?

Exceptional twentieth-century slowdown in Atlantic Ocean overturning circulation

Stefan Rahmstorf, Jason E. Box, Georg Feulner, Michael E. Mann, Alexander Robinson, Scott Rutherford & Erik J. Schaffernicht

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.

Published in Nature Climate Change [link]; full manuscript available [here].

Stefan Rahmstorf has a post at RealClimate Whats going on in the North Atlantic?  Excerpt:

The North Atlantic between Newfoundland and Ireland is practically the only region of the world that has defied global warming and even cooled. Last winter there even was the coldest on record – while globally it was the hottest on record. 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.

Climate models have long predicted such a slowdown – both the current 5th and the previous 4th IPCC report call a slowdown in this century “very likely”, which means at least 90% probability. When emissions continue unabated (RCP8.5 scenario), the IPCC expects 12% to 54% decline by 2100. But the actual past evolution of the flow is difficult to reconstruct owing to the scarcity of direct measurements.

What is new is that we have used proxy reconstructions of large-scale surface temperature (Mann et al, 2009) previously published by one of us  that extend back to 900 AD to estimate the circulation (AMOC) intensity over the entire last 1100 years. This shows that despite the substantial uncertainties in the proxy reconstruction, the weakness of the flow after 1975 is unique in more than a thousand years, with at least 99 per cent probability. This strongly suggests that the weak overturning is not due to natural variability but rather a result of global warming.

Observations

Well, if there is anything I distrust more than climate model simulations of decadal to millennial scale ocean circulations and internal variability, it is Mannian proxy analysis of same.  It seems like strip bark bristlecones and Tiljander sediments can tell us about Gulf Stream flow rates, as well as global temperatures. Remarkable.

So what do the actual ocean observations have to say?  Anthony Watts has an extensive critique of the paper, pointing to a 2014 paper by oceanographer Thomas Rossby: On the long-term stability of Gulf Stream transport based on 20 years of direct measurements.   The title pretty much speaks for itself, but Rossby had this to say in an interview:

“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.”

In 2010, NASA issued a press release NASA Study Finds Atlantic Conveyor Belt Not Slowing, citing a paper published by Josh Willis of JPL using measurements from ocean-observing satellites and profiling floats.  Punchline:

For now, however, there are no signs of a slowdown in the circulation. “The changes we’re seeing in overturning strength are probably part of a natural cycle,” said Willis. “The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling.”

Pierre Gosselin cites additional critiques from German scientists.   Notably:

Climate scientist Martin Visbeck of the GEOMAR Helmholtz Centre for Ocean Research in Kiel sees Rahmstorf’s assertion of the results critically: ‘The study’s focus on the sub-polar part of the Atlantic and the spectral analysis are interesting,’ he says. But there are other AMOC assessments that point to a completely other development. The paper does not offer any strong indication of the development of the AMOC during the past fifty years.”

So, who you gonna believe?  Climate models and Mannian proxies, or direct and satellite observations of ocean circulation?

Atlantic Multidecadal Oscillation

What is going on the high latitudes of the North Atlantic can’t be understood without the context of the Atlantic Multidecadal Oscillation. If you are unfamiliar with the Atlantic Multidecadal Oscillation (AMO), see this summary.  For reference, the AMO figures prominently in the stadium wave.  While the method to define the AMO is still debated, here I show the canonical analyses from NOAA.

The monthly values of the AMO are shown below.

Slide1

A blow up of the more recent data (through Dec 2014) is shown below:

Slide2

While the AMO index shows substantial variability, there are multi-decadal periods when the index is predominantly positive (warm) and negative (cool).  To the extend that past behavior is any guide to the future, the current warm phase is expected to transition to the cool phase sometime in the 2020’s.  While the the 1995 transition was sharp, the transition to the next cool phase might be sharp, or it might ‘flicker’ for a few years or even a decade.  We’ll have to see how this plays out.

There is some evidence evidence that the warm phase of the AMO has peaked circa 2007, see the upper ocean heat content data shown below.

Slide3

JC summary

What we are seeing in the high latitudes of the North Atlantic is natural variability, predominantly associated with the Atlantic Multidecadal Oscillation.  Based open observational analyses, there is no sign of a slowdown in the Gulf Stream or the Atlantic Meridional Overturning Circulation.

Now, I am very interested in the AMO, since it strongly influences Atlantic hurricanes, Arctic sea ice, and Greenland climate.  We are already seeing a recovery of the Atlantic sector of the Arctic sea ice, and some hints of cooling in Greenland.

With regards to Atlantic hurricanes, Bill Gray and Phil Klotzbach are looking a new definition of the AMO that they feel relates better to Atlantic hurricane activity [link], and they are seeing a transition to negative values.

And finally, the AMO does not act in isolation (e.g. the stadium wave); there are very interesting things going on in the Pacific also – perhaps a topic for a future post.

 

267 responses to “Whats up with the Atlantic?

  1. Every climate alarm between now and Paris is a lie

    • From Wuwt yesterday…

      “Pierre Gosselin over at “No Tricks Zone” is reporting that within a day of its publication, the paper from the German Potsdam Institute for Climate Impact Research has now been debunked and denounced by German climate scholars, some of whom side with the warmer view of climate. He writes:”

      http://wattsupwiththat.com/2015/03/24/mann-on-the-run-latest-paper-dead-at-birth-rejected-by-german-warmist-scientists-deletes-inconvenient-facebook-challenge/

      • It would be very convenient if this mob of doubters would use the opportunity to heave the hockey stick under the bus. It’s the only way to get traction for forward progress, and the opportunity is unprecedented.
        =========================

      • Mann has put up an easily debunked conjecture all while pointing at the ‘hockey stick’ data to justify his conclusion. What we may be seeing is Mr. Mann putting his thumb in the eye of everyone who participated in the charade by putting their reputations behind supporting his work all of these years. Perhaps this is his way of coming clean –e.g., owning-up to the fraud, admitting global warming is nothing but a hoax and a scare tactic and apologizing for the hoodwink, diminishing the credibility of science and wasting the country’s scarce resources.

      • David Springer

        Arctic sea ice melts from both above and below. The accelerated melt rate in the past two decades speaks to an acceleration in AMOC not a deceleration. Plus even if 1000 year uniqueness claim is accurate that’s an eyeblink in climate history and less than 10% time window of even the Holocene interglacial which itself is a mere snippet of recent climate history.

        This paper appears to be yet another publication from the usual suspects in the cult-like science of global warming alarmism.

        http://www.impawards.com/2004/posters/day_after_tomorrow_ver4.jpg

    • “As long as people will accept cr@p, it will be financially profitable to dispense it.”
      — Dick Cavett

    • Quote of the day, Steve Mc at ClimateAudit:

      Only one thing can be surmised from Rahmstorf and Mann’s claim that the Mann et al 2008-9 network can be used to reconstruct not just NH temperature, but also SH temperatures and now Atlantic Meridional Overturning Circulation: using Mannian RegEM with the Mann et al 2008-9 network of 1209 “proxies”, one can probably “reconstruct” almost anything. Are you interested in “reconstructing” the medieval Dow Jones Index? Or medieval NFL attendance?

      Reduction ad mannium.

  2. eh? the amo is positive and is responsible of the cooling over a small north atlantic area?

  3. Judith

    ==> “It seems like strip bark bristlecones and Tiljander sediments can tell us about Gulf Stream flow rates, as well as global temperatures. Remarkable.”

    Are those the proxies they used in this research?

    • LUZR

    • The paper uses Mann et al 2008 with all available proxies for its land-and-ocean reconstruction, so yes, Tiljander and Bristlecones do make an appearance.

    • Would you believe her if she told you, joshie? Why don’t you read the freaking paper. Beg Judith to put you back in moderation, for you own good.

    • don’t miss this, it’s worse than we thought:

      http://climateaudit.org/2015/03/25/reductio-ad-mannium/

      • from the link to climate audit

        “Rahmstorf and Mann’s results are not based on proxies for Atlantic current velocity, but on a network consisting of contaminated Tiljander sediments (upside-down or not), Graybill’s stripbark bristlecone chronologies, Briffa MXD series truncated to hide-the-decline and hundreds of nondescript tree ring series statistically indistinguishable from white noise. In other words, they used the same much-criticized proxy network as Mann et al 2008-9. It’s hard to understand why anyone would seriously believe (let alone publish in peer reviewed literature) that Atlantic ocean currents could be reconstructed by such dreck, but Rahmstorf et al 2015 stands as evidence to the contrary.”

        Ok, how did the authors manage to get from tree rings and sediments to whatever it was they thought they were proving?

        tonyb

  4. This paper took only 1 day to get beat up, and WaPo did not get the message, rather relying on the Potsdam PR. It is significant that in Germany both FAZ (think New York Times) and Der Spiegel (think Time magazine) carried negative reviews with dismissive comments from other German oceanographers and climatologists. That is something of a change in momentum from the past, when Potsdam PR would just be parroted (home of Schnellenhuber, Ramstorf, and the like).
    And in true Mannian fashion, when one of the UK’s RAPID team (buoys across the Atlantic from Florida to Portugal at 26N (to study both both the warm flow north and the cold underlying flow south) asked Mann on Facebook why they had not considered RAPIDs observational AMOC data, or last years RAPID paper on natural variability in the AMOC, Mann dismissed the paper as not relevant and then disappeared the entire comment thread. Gosslin and Watts both reproduced the incident from a screen capture made by the somewhat nonplussed RAPID researcher.

  5. Danny Thomas

    What? From the 3/23 W.P. article: “That may sound surprising, but here’s how it works. We’re starting out from a situation in which sea level is “anomalously low” off the U.S. east coast due to the motion of the Gulf Stream.”
    But from 2/25 W.P. article: http://www.washingtonpost.com/news/morning-mix/wp/2015/02/25/mysterious-east-coast-flooding-caused-by-unprecented-surge-in-sea-level/

    Does the Washington Post read the Washington Post?

    • Nice catch. Now we know their memory capacity is less than one month.

      • Danny Thomas

        Rud,
        I was beginning to think that that which is considered a “climatic time scale” had shortened just a bit. I emailed the author of this article the one from 2/25 for his interest along with the Nasa piece. Will let ya know if he responds.

    • Curious George

      Danny, congratulations. A great catch. Another attempt to redefine things – the Gulf Stream, in this case. Nothing is immune to Progress!

      • Danny Thomas

        Curious,
        Thanks. Find the same on the west coast: http://www.usatoday.com/story/weather/2015/03/02/california-drought-climate-change-global-warming/24262559/
        vs.
        http://www.nbcnews.com/science/environment/global-warming-isnt-causing-california-drought-report-triggers-storm-n263941
        Good news for me is I’ve stopped feeling like I’m missing something in trying to get a handle on this whole global warming (or is it climate change) thingy.

      • Danny, your discoveries are worthy of a guest post here. Welcome to the crowd! I do hope my most recent book may have helped a bit with your enlightenment. Lead on.

      • Danny Thomas

        Rud,
        Not even close but thanks for quite kind words. I’ve come here due to discomfort with seeing and hearing differently than some seem to and due to the lack of understanding so much have to assume that the issue lies with me. So many on both sides have shared so much allowing me to know to look a bit more deeply and as a result I find I’m still seeing and hearing differently than some (there’s circular logic, eh?). At this point, it’s damnedifIknow. Progress has gone from firmly in the middle to, well, firmly in the middle.

      • Danny

        It’s catastrophic climate change, not just run of the mill climate change. It must be true as I heard the phrase on the BBC less than an hour ago.

        It will get steadily worse in the run up to Paris. By then it will be unbelievably awful climate change.

        Tonyb

        Tonyb

      • Danny Thomas

        TonyB,
        “it must be true as I heard the phrase on the BBC less than an hour ago.”
        Try changing the channel (not the big English one as who knows where that would lead) and I’d guess you’d find a differing report.

  6. JC summary:
    …….
    Now, I am very interested in the AMO, since it strongly influences Atlantic hurricanes, Arctic sea ice, and Greenland climate.
    …….

    That is indeed worthy cause; on the other hand my interest is far less altruistic. I am very interested in the AMO, since it is only reasonably well documented ocean area where the natural climate variability can be associated with combination of the past solar activity and the geo-dynamics.

    • Every time geomagnetic storm (visually manifested as an aurora) hits the polar areas magnetic needle swings left to right or vice versa, temporarily slightly changing declination angle; the changes are measured by magnetometers at dozens of geomagnetic monitoring stations located around the globe. From these measurements a global greed map of annual changes in the s.c. ‘east geomagnetic component’ is consternated. The far North Atlantic area around 60 degrees north shows a unique response as illustrated here:
      http://www.vukcevic.talktalk.net/AMO-0.gif
      It is obvious that the AMO may not be a direct response to the solar impact, but summarily dismissing existence of an indirect link may not be advisable.

  7. There is this paper. it says:
    It is slowing, but it is natural
    http://eprints.soton.ac.uk/356498/1/2014_os_smeed_etal_Observed_decline_of_the_AMOC.pdf

    • > There is this paper. it says: It is slowing, but it is natural

      The word “natural” does not seem to occur in the text.

      • Danny Thomas

        Willard,

        Kinda does:”Our observations indicate that the actual
        change over the last decade is much greater. The magnitude
        of the observed changes suggests that they are a part of
        a cyclical change rather than being directly linked to the projected
        anthropogenic AMOC decrease.” (Pg 34 of paper, section 4.1)

      • P36; ‘suggesting that this decrease represents decadal
        variability in the AMOC system.’
        P38 Reference, Knight JR: ‘ A signature of the persistent
        natural themocline circulation cycles in an observed climate.’

      • Edit, ‘thermohaline.’

      • Thank you Danny. Here’s the full paragraph:

        Excluding the anomalous year of 2009, the mean AMOC for the second half of the 26◦ N measurements (2008–2012) is about 1.6 Sv (90 % c.i. 0.2 to 3.0 Sv) lower than the first four years. Including 2009 increases the reduction to 2.7 Sv (90 % c.i. 0.3 to 5.1 Sv). Model simulations predict a decrease of the AMOC in the 21st century in response to increasing greenhouse gases of the order of one half a Sverdrup per decade (IPCC, 2007). Our observations indicate that the actual change over the last decade is much greater. The magnitude of the observed changes suggests that they are a part of a cyclical change rather than being directly linked to the projected anthropogenic AMOC decrease. A much longer time series would be needed to identify a trend of the magnitude associated with greenhouse warming in model simulations. Thomas et al. (2012) looked at how the components of the AMOC changed during a warming scenario in a model simulation and found that the reduction of the AMOC was primarily a reduction in southward flow of deep water balanced by a reduced Gulf Stream with little change in the strength of the gyre circulation, which appeared to be determined by Sverdrup balance. This contrasts with our observations that show no significant change in the Gulf Stream transport over the 2004–2012 period when the AMOC is decreasing.

        http://eprints.soton.ac.uk/356498/1/2014_os_smeed_etal_Observed_decline_of_the_AMOC.pdf

        They repeat about the same thing in their conclusions.

      • Danny Thomas

        Willard,

        You are correct. They were more specific in the conclusion:” This trend
        is an order of magnitude larger than that predicted by climate
        models associated with global climate change scenarios, suggesting
        that this decrease represents decadal variability in the
        AMOC system rather than a response to climate change.”

        So, please, I thank you. (I could not quite tell if the thanks was missing a sarc tag so will ask, did you read it differently as sometimes I miss subtlties?) (In other words, did I score a point this time?) :—)

      • I think the authors are saying that their observations contrast with the expected results, Danny. They have not found any trace of antropogenic decrease, and suspect they might need more data. Which is unsurprising, considering that climate scientists lobbying, if I may borrow TonyB’s conception of lobbying.

        This does not mean that their observations showed that the slowing was natural. Absence of evidence is not evidence of absence and all that jazz.

        Mr. T.’s a mean cookie.

      • Danny Thomas

        Willard,

        No argument with observation being different than models projections, but this:”this decrease represents decadal variability in the
        AMOC system rather than a response to climate change” seems pretty clearly a statement of the natural portion having been parsed out to me. Trying to insure that’s not some sort of bias on my part, do you really not see that?
        So, it’s slowing and does so “naturally” normally (that cyclical nature thingy) and because the results of observations don’t match the models the conclusion is not presumed natural as that can’t be specifically proven even after they state the “decrease represents decadal variability in the
        AMOC system rather than a response to climate change”?
        Wow Willard! What play number is that in the climateball handbook?

        The sun exists, but since the sun can’t be proven to have not been made by man as the models showed, it cannot be presumed to be nature? Did I reframe that accurately?

      • Danny Thomas,

        Ever read Alice’s Adventures in Wonderland? Willard studied logic under the Queen of Hearts.

        “Decarbonization first – science afterwards!”

      • Danny Thomas

        GaryM,
        Quite obviously I’m misreading that somehow. If you can explain it to me I’ll wait while enjoying these mushrooms and …………what was I saying?

      • > but this:”this decrease represents decadal variability in the
        AMOC system rather than a response to climate change” seems pretty clearly a statement of the natural portion having been parsed out to me.

        Not sure what you mean there, Danny. Are there tags missing?

        I think “this decrease” refers to “the magnitude of the observed changes.” Since the variability is quite greater than what the models assumed, they’d need more data, more models, or a bit of both. This is not inconsistent with TonyB’s conception of lobbying for more data or more expensive models.

      • Danny Thomas

        Willard,

        Maybe if I changed it to: decadal variability represents decadal variability in the AMOC system rather than a response to climate change. I wasn’t a language major so maybe that’s the reason for my obvious lack of understanding of that sentence.
        w/r/t:”Since the variability is quite greater than what the models assumed………….” then maybe it’s just a “pause” in the observations and the models are really just fine after all. Could be that I suppose.

      • > maybe it’s just a “pause” in the observations and the models are really just fine after all.

        I doubt it, Danny. The authors do say that Thomas et al’s prediction contrasts with their observations. They also say that the change over the last decade is so great that they can’t validate IPCC’s prediction, since the signal, if any, is drowned into decadal variability.

        The authors’ conclusions seem to indict both the models and the data. In other words, the authors seem to lobby (H/T TonyB) both more data and better models.

        At least that’s what I read from the paragraph.

        Hope this helps,

        W

        PS: I acknowledge the many interesting questions in your previous post, and will return to them another time, perhaps not when you’ll expect it.

  8. But the real value of this paper was the headline. Always, but always, the headline. Just like an error in reporting of any sort. No one bothers to go to the bottom of page 17 to read the retraction. Even if this paper gets demolished by other scientists with valid criticism. The public will never know that part of the tale. They will only remember the headline.

    Worthy of Madison Avenue.

    • Maybe someone’s trying to sneak up on Obama like they did letting Hillary think her server was secure.
      ===================

    • “headlines”

      Exactly right. It’s a cynical game they play, but it’s effective. For just one example, Cook’s cooked up consensus paper. It’s manifest crap, and likely most of them know it, but it doesn’t matter. They all seize on it, and treat it as fact. I’m 64 years old, and find myself amazed at how naive I was just a few years ago. I never would have believed this stuff…

  9. That may not sound like much, but the paper suggests a weakening this strong has not happened at any time since the year 900. Moreover, this is already more weakening than scientifically expected — and could be the beginning of a further slowdown that could have great consequences.

    Of course it is different from what they expected. They don’t understand what happened before. They have turned the real data into hockey sticks.

    Roman Warm Period, Medieval Warm Period, Modern Warm Period.
    What has happened in these natural cycles in the past does happen again.

    The cycles do repeat, again and again. The only thing that is different this time is that we have the ability take better data and we have the ability to watch. These past cycles are not in climate models, but these past cycles are in ice core data and in the history books.

  10. It’s difficult to comment on this without sounding like a paranoid conspiracy theorist, but wottheheck.

    Since around November 2014 a massive propaganda push seems to be happening with alarmist papers appearing regularly every week.

    Yes, alarmist papers appear all the time (publish or be damned) but lately they are being promoted with far more vigor.

    The members of the (non-existent except in my dreams) cabal have agreed to dig through their various reject bins and trot out anything alarmist, no matter how poorly-founded, because the publicity machine will get mileage out of them nonetheless.

    The fact that the Dying Gulf Stream hypothesis has been thoroughly falsified is not to be allowed to stand in their way.

    We are witnessing possibly the most powerful propaganda machine of all time in operation. Regrettably it is likely to enjoy considerable success.

  11. Bernd Palmer

    So we have a case where 97% of the climate scientists agree (a conspiracy-free consensus) that the Atlantic meridional overturning circulation is NOT slowing down. And now Mann is sitting on the wrong side of the fence …

  12. “This strongly suggests that the weak overturning is not due to natural variability but rather a result of global warming.”

    Not possible it terms of forced warming. Increased forcing of the climate increases positive NAO/AO, while the low AMOC events recorded by RAPID-AMOC are all during negative NAO/AO periods.
    The most telling low AMOC events are in the summers of 2007 and 2012 when Arctic sea ice extent was at record lows. Plainly, negative NAO/AO periods cause low AMOC events, and is the direct means for warming surges of the AMO and Arctic Ocean.

    I have looked a couple of times through SST’s south of Greenland during negative NAO periods, and all I am seeing is warming there, the regional SST cooling occurs during positive NAO/AO periods. So maybe they are referring to cooling there in the last couple of years as the NAO/AO has been more positive.
    http://weather.unisys.com/archive/sst/

    J.C.:
    “There is some evidence evidence that the warm phase of the AMO has peaked circa 2007, see the upper ocean heat content data shown below.”

    Given a repeat of a ~69yr envelope, the AMO should begin its cold mode from the mid 2030’s, and reach its coldest in the mid 2040’s. Typically in its cold mode, the AMO moves in phase with solar cycles, and in its warm mode, out of phase with solar cycles. That pattern should produce a temporary cooling if the AMO and Arctic around this sunspot maximum, and warm especially strongly through the next decade, as it will be the weakest part of this solar (grand) minimum:
    http://www.woodfortrees.org/plot/esrl-amo/from:1880/mean:13/plot/sidc-ssn/from:1880/normalise
    With UK temperatures on completely the phase and moving with the solar cycle and cooling:
    http://snag.gy/MTnui.jpg

    J.C.
    “And finally, the AMO does not act in isolation..”

    Yes it appears to be a global signal, and if you compare SST’s from each hemisphere, the periods of divergence may well relate directly to AMO warming episodes.

  13. These BS horror story papers along with the obligatory mainstream media hype are appearing daily. They are trying to scare the public ahead of the next big climate confab. It’s not going to work for them. They been crying wolf for way too long. And the pause is killing the cause.

  14. stevenreincarnated

    Perhaps I missed it, but I didn’t see where Lund et al 2006 was referenced. That certainly would have been relevant. I’m suspicious the cold spot might just be fresh water run off from Greenland since it seems pH is also lowering very fast in the same general area.

  15. “To the extend . . .” should read “To the extent . . .”.

  16. Pingback: Georgia Tech Climatologist Curry: “No Sign Of Slowdown” In AMOC…Sees Atlantic “Arctic Sea Ice Recovery”, Hints Of Greenland Cooling

  17. I did this quite a while ago regarding the flipping of the other osculation, the PDO

    http://oi59.tinypic.com/9tiw4w.jpg

    I am not one of the chosen climatologists who is able to speak on such things (according to the CAGW crowd) or anything, of course, but from my personal perspective it seems as though the PDO is largely responsible for the planets temperature trends while the AMO decides which of the poles will be holding heat at that time

    For an example of what I mean, compare

    https://curryja.files.wordpress.com/2015/03/slide13.png?w=500&h=375

    with

    http://www.climate4you.com/images/NuukGreenlandAirTempSince1866.gif

    http://www.sott.net/image/image/s5/113438/full/NorthernHemisphereSeaIceAnomal.png

    and

    http://upload.wikimedia.org/wikipedia/commons/8/8d/Southern_Hemisphere_Sea_Ice_Extent_Anomalies-Mar.png

    I, of course, could be completely wrong on that – but overall Temperature trends are definitely following the PDO, while regional warming periods and Ice Extents seem to be following the AMO fairly well.

    Meanwhile, the two separate 20-year warming periods seen since better records have been kept (roughly 1920-1940 & 1980-2000) directly correspond to large spikes in the AMO cycle, a positive PMO and solar activity increases all taking place at the same time.

    If we were ever able to document the AMOs 1,000 year history like we have for the PDO, it would be interesting to line it up with known solar activity and the below known history of the PDO to see if we can get a proper temperature for the entire time period as well as better understand the regional trends of that era

    http://upload.wikimedia.org/wikipedia/commons/thumb/1/11/PDO1000yr.svg/800px-PDO1000yr.svg.png

  18. Wait, RealClimates authors are using the Mann 2008 proxy set (which was also used in Mann 2009) in a new paper? Without noting their hockey-stick shape depends entirely upon uncalibratable, double-counted, upside down proxies and bristlecone tree ring data? Or acknowledging over a hundred proxies used in the Mann 2008 data set use instrumental data? As in, the proxies were truncated to remove data then had instrumental data spliced in instead?

    They are! They actually have the audacity to say:

    To obtain a long-term reconstruction of the AMOC index requires long-term reconstructions of both the Northern Hemisphere mean temperature and SST of the subpolar gyre. For the Northern Hemisphere mean, Mann et al.12 produced reconstructions using two different methods, composite-plus-scale (CPS) and errors in variables (EIV). Here we use the land-and-ocean reconstruction with the EIV method using all the available proxies, which is the reconstruction for which the best validation results were achieved (see Supplementary Methods of Mann et al.12).

    Meaning they’re not even pretending to address the fact they used uncalibratable data with the opposite orientation designated by the authors! How is this science? Or honest?

    Heck, I don’t use the word lightly, but how is that not fraud?

    • Wait’ll Steve gets out of British Columbia and notices this.
      ===============

    • richardswarthout

      Brandon

      +1. There are a group of climate people (almost said scientists) that are doubling down on discredited proxy reconstructions. By doing so this group have crossed the line; the first hockey stick could have fallen under the “mistake” category. It is now obvious that they are purposely misleading, and the media will get it; fool me once….

      Richard

      • The subterfuge has been clear for six or seven years since Mann carefully did not do a no-Tiljander, no-splitbark bristlecone temperature reconstruction. Will the MSM snap to it this time? Maybe after the Snow Ball in Paris.

        Not likely before.
        ============

    • Well if you were a detective wouldn’t you call that Mann’s MO?

    • Hey Brandon, since you are clamoring to be the next Tim Ball-Mark Steyn, I suggest you include the statute number of the “fraud” offense that you are alleging. That should get Mann and his pals riled up real good. I just hope they don’t go after Judith for letting you use her place to holler. You should trademark “Save Brandon”. You’ll need to sell a lot of coffee mugs and t-shirts.

      • Don, got Brandon’s back a bit on this. One reason why I have been posting so proliferously on this awful paper on multiple blogs. Almost better than a subpoena’d deposition. (Did my last one of those just three months ago.) Indelible. And notice the non ‘facts’ crafted in always.
        Now, never used the word fraud. Have used, and will repeat, probable academic misconduct in this paper, in multiple ways. In their world, worse. And have posted irrefutable evidence as to why that assertion must be true. misrepresentarion of F 6. Failure to cite other recent papers. Failure to cite critiques of their prior work relied upon…

      • I don’t doubt that the paper is a stinker, Rud. But am not expecting that those monkeys are going to suffer any consequences for it. Brandon has all but flatly stated that he is trying to provoke a suit from Mikey to make a name for himself in the climate debate. He should confine his provocations to his own blog. At the least, he has left Judith open to charges that she condones pipsqeaks making fraud accusations against her fellow scientists.

  19. Judith Curry.

    You may wish to find another summary of AMO. The one provided reads:

    “During warm phases of the AMO, the numbers of tropical storms that mature into severe hurricanes is much greater than during cool phases, at least twice as many. Since the AMO switched to its warm phase around 1995, severe hurricanes have become much more frequent and this has led to a crisis in the insurance industry.”

    Didn’t we just see that the number of Atlantic hurricanes making land fall and the severity of hurricanes for the last number of years has been low in regards of severe hurricanes and zero in terms of those making landfall?

    • But do they answer when you do call them?
      ==============

      • Kim

        NOAA/NASA certainly answers when called, its just what do you do with the information they provide? All I can figure is that they are authoritatively wrong. Given that this is a Governmental outfit, I guess I can live with that.

    • I read the provided link to Grey’s newest hurricane discussion. It is a bit more complicated. The issue is not less hurricanes. The issue is no US landfalling hurricanes since the horrific 2004-2005 seasons. Grey identifies three factors. First, the storms are forming earlier (nearer Africa). That means their ‘natural’ turn north then northeast is happening out in the ocean. Second, there is a ‘bermuda/azores’ high since 2008 associated with the Atlantic gyre (AMOC leakage, if you will) that is helping push this turn earlier. Third, he says we have just been very lucky and should not expect that luck to hold.

  20. The data seems to support what Ulric ,has said in his post at 2:54 pm.

    Strong Solar Maximum Activity equates to a +NAO,+AMOC, AMO Cooling Europe Warm, Arctic Cold.

    Weak Solar Maximum Activity equates to a -NAO,-AMOC,AMO Warming, Europe Cold, Arctic Warm.

    Where I part is although the AMO may be in anti phase with solar activity , I think sea surface temperatures as a whole on a global basis are in phase with solar activity.

    Data supporting this I will send on my next post.

    In addition I think some of what governs the AMOC is internally generated by terrestrial changes here on the earth.

    I also believe a stronger AMOC will promote overall warming for the N.H. if it should occur while a weaker AMOC will promote overall cooling for the N.H., but not to the tune of 100% (maybe 75%)where some areas in the N.H. will have a temperature response in anti-phase to the AMOC ‘S strength.

    • SDP:
      “Where I part is although the AMO may be in anti phase with solar activity , I think sea surface temperatures as a whole on a global basis are in phase with solar activity.”

      Global SST+AMO:
      http://www.woodfortrees.org/plot/esrl-amo/from:1880/mean:13/detrend:-0.6/offset:-0.4/plot/hadsst3gl/from:1880/mean:13

      “I also believe a stronger AMOC will promote overall warming for the N.H”

      It would give the potential for more surface warming, but not until a weaker signal causes El Nino and AMO warming to express what had been gained during colder AMO & ENSO modes.

      • “I also believe a stronger AMOC will promote overall warming for the N.H. if it should occur while a weaker AMOC will promote overall cooling for the N.H., but not to the tune of 100% (maybe 75%)where some areas in the N.H. will have a temperature response in anti-phase to the AMOC‘S strength.”

        I have a post awaiting moderation that basically says the same thing, ironically, pointing out AMO might dictate where heat is accumulating while…

        “I think sea surface temperatures as a whole on a global basis are in phase with solar activity. “

        To which I say it is Solar Activity combining with flips in the PDO driving global temps; (using this old sarcastic graph I made because don’t feel like making another) like such:

        http://oi59.tinypic.com/9tiw4w.jpg

        So to quickly summarize my thought process; Solar largely dictates SST, PDO dictates if said SST is to be released into the air or absorbed by the sea, AMO dictates intensity and location of release if it is to be released.

      • And if you read the paper, they claim that the AMOC weakened from about 1975, which is probably later in 1976 going by the solar wind data. Strong AMOC during the coldest AMO years with multi-year La Nina episodes.

      • “they claim that the AMOC weakened from about 1975, which is probably later in 1976 going by the solar wind data. Strong AMOC during the coldest AMO years with multi-year La Nina episodes.”

        Interesting date too, as the AMO started its climb and the PDO flipped to Positive in 1967/1977

        Re the article
        “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.”

        Let’s take a look at what Greenland looked like in the late 1970s and see how that lines up

        http://www.climate4you.com/images/NuukGreenlandAirTempSince1866.gif

        Humm… so Greenland was experiencing a lot of Ice Melt during its coldest period since the Little Ice Age, were they?

        This paper also begs to differ

        http://api.onlinelibrary.wiley.com/asset/v1/doi/10.1029%2F2010JD014918/asset/image_n%2Fjgrd16813-fig-0002.png?l=Cgg2pVVsCMz6GyJFD9PqfXFeTnOhBCc2XKEdrHvs2QBTaaQd%2FMzdOkHlDU5VFoInL%2FYocYEVfuIZQWFv%2BWa%2FEg%3D%3D&s=%22545176d034334becb4096ea1f718c1c4%22&a=wol

        http://onlinelibrary.wiley.com/doi/10.1029/2010JD014918/full

      • Unfortunate some images don’t embed.

        http://www.worldclimatereport.com/wp-images/Greenland_JGR_fig3.JPG

        That is the second image if one wants to see it without leaving the page

      • D.S.
        The Nuuk series is coastal, and the trends are generally the inverse of the solar trends, with strong warming from the mid 1990’s with the AMO, but inter-annual variability also appears to be effected directly by warmer N.H. summers.
        The other chart shows the melt index *negative* in the 1970’s.

      • Correct. And as I stated in the previous post, that leads to this problem

        “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.”

        Current positive melting index is contributing to weakening of the AMOC, while the negative melting index of the 1970s supposedly created AMOC weakness. That the AMOC has been recently increasing (they personally dismiss it as being too short a period of time to take seriously) as the melt index is positive indicates they seem to have their entire theory completely backwards.

        As a side note, this evening WUWT provided a 2010 NASA report stating the following
        “Willis found evidence that the circulation had sped up about 20 percent from 1993 to 2009. This is the longest direct record of variability in the Atlantic overturning to date and the only one at high latitudes.”

        Again, opposite

      • “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”

        It’s a shame that a slow AMOC is the wrong sign to be associated with increased forcing of the climate then after all that handiwork.

        “Current positive melting index is contributing to weakening of the AMOC,”

        More like negative NAO is responsible for both.

        “while the negative melting index of the 1970s supposedly created AMOC weakness.”

        It wasn’t negative in the 1970’s it was strong then. It *weakened* from *later* in the 1970’s.

      • Sorry I should have wrote that the AMOC *was not weak in the 1970’s*.

  21. http://s23.postimg.org/691bp3lln/Sun_SST_AMOC.png

    Research of Paul Vaughn ,which shows data showing a strong correlation of solar activity to sea surface temperatures for the globe overall.

    • I’ve long thought Paul Vaughn was on to something, but I could never figure out just quite what. This is helpful.
      ====================

    • Sunspot integral?

      Let me guess. Sunspots don’t correlate with global temperature so they needed adjusting. But of course it’s fine because there’s absolutely no justification for using the integral other than to get a fit

      I note the record hot year of 2014 is absent on the graph too.

  22. Pingback: Reductio ad mannium « Climate Audit

  23. When a paper such as this is published, the granting agency should have to be repaid.

  24. https://wattsupwiththat.files.wordpress.com/2015/03/greenland-surface-mass-budget.png

    Greenland Ice Cap Data. If it were to decline that would be the only thing AGW theory could cling to , but the problem is it is not melting. See the data..

  25. Not so sure about who but pretty sure about what I’m gonna believe: that Climate models and Mannian proxies will support just about any notion a card-carrying member the Earth-on-Fire-Red-Brigade wants them to, irrespective of satellite observations, or common sense, or anything Uncle Commie wearing a sweater by the fireside dreams up for us to believe next.

  26. The worst part of this is not that this was very poor paper , given the authors this would after all expected, but that once again ‘peer review’ totally failed to find out how poor it was and instead another hand waving , or should that be back starching , exercise was seen.
    Perhaps it really is ‘settled science’ after all , if you play the three wise monkeys and see no error , hear no error and certainly don’t speak about any error .

  27. One of the most impressive talks I ever saw at the CCSM conferences was some dudes from Los Alamos. They solved some variant of an ocean model for a steady state AMOC and then did a bifuraction analysis.
    Found it. NOt sure how meaningful without the accompanying talk, but:
    http://www.cesm.ucar.edu/events/CCSMAnnualWorkshop2007/PresentationsPDF/weijer_slides3.pdf

  28. http://stateoftheocean.osmc.noaa.gov/atm/amo.php

    AMO is neutral now. It is going to be interesting to watch.

  29. Over at No Tricks Zone Rahmstorf, Mann et al paper
    under fire.Interessant that Mann responds to a critique
    by Jaime Jessop and later deletes their interchange.
    Can’t have felt too confident that his response could
    stand up to public scrutiny. Sort of an old trick, yer
    might say.

    http://notrickszone.com/2015/03/24/dead-at-birth-german-warmist-scientists-slap-down-rahmstorfmann-amoc-paper-offers-no-strong-indication/#sthash.T06Ou56u.dpbs

    • Mann realized Jaime wasn’t acting in good faith and so deleted him.

      • Is there no disgrace by the CLImate Establishment that you will not slavishly defend? You have no idea whether she was not acting in good faith — her comments certainly look serious and well formulated. Mann’s idea of “not in good faith” is anything that might challenge or embarrass him.

      • Any excuse to hide a critique will do the trick.
        Say lets not bend over backwards, Feynman style,
        to critically examine flaws in our work, (Yamal
        sampling ) or statistical method, ( temperature
        splicing) Good faith yer say?

      • The fact he took a screenshot demonstrates what he was up to. Mann sniffed him out. Clever man.

      • Sometimes when dealing with tricky man it’s best ter
        document, like in transactions, signatures on the dotted
        line. Speaking of signatures, I hear the CO2 fingerprint
        fer man made warming is missing in the troposphere
        and CO 2 is free ter go.

      • Her.

      • The fact that she took a screen shot says nothing about bad faith on her part (what a silly idea, taking a screen shot means you are engaging in bad faith, ha ha)… only the bad faith on Mann’s part. It indicates an awareness of Mann’s chronic bad faith and an awareness that Mann deletes anything that could challenge or embarrass him in his narrative. He is a disgrace, as is anyone who defends his behavior.

      • Wait. I understand the problem here, I’ve seen it before at Bishop Hill with ATTP. It’s a simple misunderstanding. By ‘good faith’, lolwot means ‘gullible fool’. Mann realized Jamie wasn’t acting like a gullible fool and so deleted him.
        It’s an easy mistake to make. g.f., good faith, gullible fool; they’re practically similar looking if you squint.

      • I get it now, simply define “bad faith” as anyone not subservient to Mann, and it all falls into place easily….. “good faith” is keeping the faith, upholding the CAGW religion, and “bad faith” is any kind of failure to worship at the shadow of Mann.

  30. Steve McIntyre has given this nonsense a stiff uppercut as well. Seems the Mann so loves his upside down proxies and hopelessly wrong bristle cone proxies etc too much to abandon them. What a hoot.

    http://climateaudit.org/2015/03/25/reductio-ad-mannium/#comments

  31. “Anthony Watts has an extensive critique of the paper, pointing to a 2014 paper by oceanographer Thomas Rossby: On the long-term stability of Gulf Stream transport based on 20 years of direct measurements.”

    And yet

    “The Rossby paper is not that relevant to our paper because it deals with much shorter time scales (20 years of data, while we use decadally smoothed data over 1100 years) and with the Gulf Stream rather than the AMOC. Actually for those 20 years analysed by Rossby our index shows an increase in the AMOC – but that is so small that it would be within the uncertainties of Rossby’s calculated trend in the Gulf Stream. So no inconsistency there.” – Stefan Rahmstorf

    OH DEAR has Dr Curry just been caught jumping to a conclusion based on the TITLE of a paper? and citing Anthony Watts as a source of all things?

    “The title pretty much speaks for itself,”

    Wow what careful scientist Dr Curry is. The title speaks for itself indeed!

    • richardswarthout

      Lolwot

      You are to be admired. Mann et al are on the Green Mile, yet you stand by them.

      Richard

    • Lolwat, Echoing TonyB, boy, have you warmunists got this one wrong. Big time. Just trace the published papers as written and accepted. And now indelible. amoc is not just a southern Greenland phenomenon, as was expalained in his paper, which part he now attempts to disclaim.
      First rule of Army holes. if in one and want out, STOP DIGGING.

    • Music has just never been the same since the ’70s

      • Its been all downhill.

      • It’s not all bad.
        I think it’s a matter of brain development, and for many (ymmv), for some reason, peoples taste in music “freezes” in their late teens, and that corresponds to the neural networks that decomposes sound in your brain, and when you hear a different tempo of music, until you’ve built your own network for that type of music, it sounds like noise. Which is why everyone’s parents disliked their children’s music, calling it noise. But you can build the networks, maybe you’ll never like it, but it will be less noisy.

      • I agree micro. There’s a lot of stuff today I like.
        Being a musician tho, I miss the era of the bands!

      • Andrew Russell

        As Kevin Klein’s character says in The Big Chill: “There’s been no decent music since 1969” :-)

      • I wish I could hear Janis Joplin live……and Maria Radnor.
        ========================

      • Ah, Maria Radner. Wasn’t familiar enough with her to have the spelling correct, as if that were what mattered about her.
        ================

      • Jan Stunnenberg

        @Kim
        Þnx for pointing me to Maria Radner.
        She was on the 4U9525 (Airbus320) flight that crashed this week.
        I didn’t knew that although I live in Germany.
        The Heavenly Choir has a new Angel to join.

        To this discussion I’d like to add my opinion:
        They are looking for a new narrative to get over the coming cold after the ‘Pause / Hiatus’. They know that it will get colder because of the 60y cycle.
        However their job is not finished jet, so they are preparing us for the cold.
        As in the 70ths of the previous century, the coming cold of the 30ths of this century needs to be explained by anthropogenic stuff.
        Remember: ‘Global Warming’ changed in ‘Climate Change’ etcetera.
        Further I’ve noticed the by and large absence of trolling in this thread.

      • Yes, Jan, the autopilot on the narrative has been set to a crash course. Passengers are banging on the door.
        ================

      • Jan Stunnenberg

        Well put!
        There is a saying here: “Dein Wort in Gottes Ohr!”, meaning
        something like: “From your lips to God’s ears.” or
        “Let’s hope so, by goodness!”

      • Gaia hears the poor passajieros.
        ================

      • As soon as I get to Hades I shall request a Zep concert. See how that goes.

  32. Repeated as posted in wrong thread.

    Here is the 1930 us weather review about the gulf stream warming at the time

    http://docs.lib.noaa.gov/rescue/mwr/058/mwr-058-03-0103.pdf

    On Page 106 item VI it is mentioned that a report is to be compiled giving gulf stream temperatures back to the earliest times. it warms and cools.

    Anyone ever come across this document as this would illustrate whether today is out of the ordinary.

    Maury also compiled useful information on the gulf stream as did the Challenger expedition over 120 years ago.

    It is not necessary to use mannian proxies . Reconstructions back 1100 Years.. Hmmm. Surely not even Jimd would attempt to defend that nonsense.would you Jim?
    tonyb

    • > Surely not even Jimd would attempt to defend that nonsense.would you Jim?

      Another glimpse beyond the candid façade.

      Compare and contrast with Sir’s own candid invitation:

      STOP DIGGING.

      http://judithcurry.com/2015/03/25/whats-up-with-the-atlantic/#comment-687035

    • As I mentioned below, that region of the central North Atlantic has cooled over the century as the rest of the world warmed. The cooling seems to have become noticeable since the 1970’s which is just as the recent global warming phase became obvious. It is a sharp divergence in temperatures on a century scale that may even be related to global warming. Whether it is a slowing down of currents or some freshwater effect, I don’t know, but they are right to point out the divergence of this region that got sharper in 2014. Skeptical comments have so far not talked about the same area, missing the point completely. As I showed below, these trends can be seen with GISTEMP analyses.

  33. Global SST+AMO:
    http://www.woodfortrees.org/plot/esrl-amo/from:1880/mean:13/detrend:-0.6/offset:-0.4/plot/hadsst3gl/from:1880/mean:13

    Ulric , your data is convincing but there is one unknown and that is during most of the time period your data covers the sun has been in an active to very active regular rhythmic cyclic mode of activity. Only since post 2005 has the sun entered a deep phase of inactivity and this was still punctuated by a recent solar maximum period of activity. What happens during a protracted solar minimum period of activity with very little rhythmic cyclic activity?
    I am confident that if sunspot numbers fall below the value of 40 on a regular basis that sea surface temperatures for the globe are going to decrease due to the fact Visible Light/Long Wave UV light will be on the decrease which penetrate the ocean surface to great depths.This despite the phase of the AMO which is all relative to what the average sea surface temperatures for the globe are in the first place.

    Where we differ Ulric, is I maintain the ultimate determination of global sea surface temperatures is solar activity ,not the AMO. The AMO is superimposed upon what ever that average global sea surface temperature happens to be as determined by long term solar activity. The AMO then making the sea surface temperature deviate from that average but not controlling the ultimate average global sea surface temperature.

    I still agree with you ,other then I think what you say is superimposed upon the determination of what the global average sea surface temperatures are in response to long term solar activity when in a very active or very inactive phase.

    I hope I have expressed this well.

    • “The AMO then making the sea surface temperature deviate from that average but not controlling the ultimate average global sea surface temperature.”

      I cannot argue with that, and in fact I never have.

      What were the AMO and SST’s doing in the deeper parts of the Gleissberg Minimum, 1879-1881 and 1885-1895?
      http://climexp.knmi.nl/data/tcet.dat

  34. I’m sure the climate and the thermohaline circulation are changing in all sort of major and minor lines and cycles. What else could they do?

    But there is a positive change we ourselves can make today. We can reject the Washington Post, on the grounds that is for big babies.

    • A serf’s list of ‘must reads,’ and ‘must listen to’s’
      decreases daily. Thank goodness fer CE Open
      Society where few comments git deleted.Mann o
      ‘ Mann!

      • Exactly. Here we get to talk back, frequently and constantly. Serfs can have their say, and toffs can connect with their inner-serfs. Deep down, we toffs know that the “organic” days of dung and smoke are behind us all – and good riddance.

        There are those who don’t like it…Ah, but that’s why we do it. If they accuse us of messing with the whole bloody Gulf Stream, that’s a measure of their desperation, not of the Gulf Stream.

      • O them organic days of the golden age, sans even oxen
        ter replace mann power. We serfs luv the steam engine
        that released us from slavery, and hope that internet
        salons like CE stem the tide of the back ter the Golden
        Age model ruled by philosopher kings of the green party.

  35. lolwot I do not understand your point. The data simply shows how the Greenland Ice Cap has varied on a yearly and seasonal basis for the past few years.

  36. “”Some critics have tried to make hay over a previous article from last year by URI Graduate School of Oceanography scientist Tom Rossby they claim contradicts our recent Nature Climate Change study finding evidence for a long-term slowdown of the Atlantic Meridional Overturning Circulation (“AMOC”). [Tom incidentally is the son of the great meteorologist Carl-Gustaf Rossby of “Rossby wave” fame: http://en.wikipedia.org/wiki/Carl-Gustaf_Rossby. He also happens to be a friend. He is one of leading physical oceanographers of our time. His scientific work is extremely thoughtful, careful, and solid].

    Rossby employs direct measurement of Gulf Stream transport using a ship-board acoustic Doppler current profiler (ADCP) over the interval 1993-2012. I have no reason at all to doubt Rossby’s findings. And they do *not* conflict with our own findings (though some have misleadingly sought to assert they do) for two fundamental reasons:
    1. One man’s signal is another man’s noise: Over the relatively short interval (1993-2012) in question, we too find little or no net trend (!). The trends that we identify in our article are longer-term in nature, and are corroborated by independent studies and independent data (e.g. Nitrogen isotope data from corals) as documented in our article.
    2. What Rossby is measuring is largely associated with the wind-driven boundary current of the subtropical horizontal ocean gyre, the warm poleward current that hugs the coastline of the southeastern U.S., the current that *physical oceanographers* refer to as the “Gulf Stream”. This is rather different from what we are looking at, which is what oceanographers instead refer to as the “AMOC” and more specifically, the “thermohaline circulation” (sometimes also called the “conveyor belt” because of the shape of the circulation cell, which in the Atlantic carries warm waters northward near the surface and cold waters southward at depth, thus providing a net transport of heat poleward). That vertical overturning circulation is driven instead by lateral density contrasts that arise due to variations in temperature and salinity. The shallow component of this ocean circulation pattern does not recirculate within the subtropical gyre and instead continues northward across the North Atlantic toward Iceland and Europe. That component is typically referred to as the “North Atlantic Drift” by oceanographers. It is not the “Gulf Stream”. But the problem: in common parlance (and numerous news articles and reports), it *is* referred to as the “Gulf Stream”.
    So in short, we and Rossby aren’t really looking at the same current system (though one might think so due to the confusing and often inconsistent use of the “Gulf Stream” terminology), and even if we were, both studies agree that there was little or no trend over the quite short interval of 1993-2012.
    It is always useful to question new studies, and subject them to the full scientific scrutiny they deserve. And Carl Sagan’s famous maxim “the more extraordinary the claim, the more extraordinary the evidence must be” certainly applies. But bad faith efforts to confuse the public by erroneously conflating two very different findings has no place in the public discourse over the science and its implications.”

    -Dr Mann

    But nevermind huh

    • Another Al Gore docudrama in the works perhaps?

    • Lolwot, See above. You efffort to refute (a la Mann) by latitudinal displacement the thesis of several refuting papers fails. Because the AMOC is by defintion one mass/thermal mass coupled system. The Atlantic Ocean is contiguous. Unless you can prove orherwise. What, won’t try that?
      What, you think we could believe some water ‘hole’ in the ocean? If so, show how much and where it is. Else, Good Night.

    • lolwot, there are a number of ocean paleo reconstructions in the region, some that actually consider salinity that find considerably more variability.

      https://lh4.googleusercontent.com/-tkWpB0eWsSY/VRNJieSUTWI/AAAAAAAANSk/MlctutrD8Io/w627-h427-no/subpolar%2Bnorth%2Batlantic.png

      Sicre et al. 2011 is one and Mietteninet al 2011 another, that might indicates Mann’s methods should be questioned a bit more strongly. It looks like he has shifted into baffling mode and lost his dazzle.

    • Oh good, lolwot, are you Michael Mann or at least one of his followers?

      I’ve desperately been trying to get him to address this thoroughly (after he dodged doing so when I confronted him personally.) Maybe you can do so for him here?

      http://oi57.tinypic.com/av1rev.jpg

      On that one, I cant understand how the “Unequivocally Unprecedented CAGW” the IPCC insists started in 1950 actually matches perfectly the “natural fluctuation” time period seen circa 1880-1950.

      I mean, if you have the exact same thing happen twice, and you write the first off as natural fluctuation, how can you then say the second absolutely cant possibly be natural fluctuation with any certainty? In fact, wouldn’t a perfectly repeating cycle of natural fluctuation be a much more logical explanation than trying to fit the square peg in a round hole by calling it completely the result of something else?

      The other question is this

      http://oi58.tinypic.com/13yowle.jpg

      How is it the age of “Unequivocally Unprecedented CAGW” has produced merely about 13 years of warming over the last 75 years?

      I mean, wouldn’t the 17% of warming contrasted against 83% flat temperatures indicate a trend of no warming with a fluke warming period? Or are we really to believe the entire 83% is the fluke part and that the 17% is somehow the real trend?

      Cant wait to hear your answers, been waiting a long time for someone in the CAGW crowd to address them!

      • > I’ve desperately been trying to get him to address this thoroughly (after he dodged doing so when I confronted him personally.) Maybe you can do so for him here?

        Another invitation.

    • Steve Fitzpatrick

      Humm. So over a 20 year period of rapid warming (http://woodfortrees.org/plot/wti/from:1993/to:2012/plot/wti/from:1993/to:2012/trend), there is no discernible change in either gulf stream flow (according to Rossby) or AMOC (according to Rahmstorf). Yet Rahmstorf is 99% certain of an unprecedented reduction compared to the last 1000 years?

      Strains credulity just a wee bit.

  37. Western academia’s fixation on global warming and climate change introduces us to what life is like in shadow of the Tower of Babel. Statisticians, McShane and Wyner found absolutely no signal whatsoever in the proxy data Michael Mann used to fabricate the apocryphal hockey stick graph that both charged and found all of us guilty of the crime of causing global warming. The hockey stick is nothing but a, bad faith effort to confuse the public and has no place in the public discourse over the science and its implications.

  38. lowot what do you think the trend will be for the AMOC going forward?

  39. Danny Thomas

    How does this fit in w/r/t hurricanes? https://www.climate.gov/news-features/blogs/enso/what-mjo-and-why-do-we-care
    Is it tracked like ACE via an index? Has it been deformed via the jet stream? This is a new discovery for me and is as a result of this post.
    Further: http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2938
    I don’t recall seeing a reference before but since it’s a short term cycle maybe it’s not considered “climatic” and is more considered to be related to weather?

  40. The headline said it all as far as I am concerned. The MCM (in the shape of the Washington Post in this case) seems to be a part of a concerted effort to keep the notion of CAGW alive for the benefit of the forthcoming Paris climate conference.

    Unfortunately this hand has been overplayed and AGW supporters (with a few predictable exceptions from the fanatical) appear to be embarrasssed into silence by what is hapening. The dead horse is starting to get on the nose.

  41. “What is new is that we have used proxy reconstructions of large-scale surface temperature (Mann et al, 2009) previously published by one of us that extend back to 900 AD to estimate the circulation (AMOC) intensity over the entire last 1100 years. This shows that despite the substantial uncertainties in the proxy reconstruction, the weakness of the flow after 1975 is unique in more than a thousand years, with at least 99 per cent probability.”

    “Despite the substantial uncertainties” in the debunked proxies as showing the temperature in the immediate vicinity of the trees from which the cores were taken, we can now determine with amazing accuracy and precision, from those same cores, the temperature and current rate of an ocean thousands of miles away from these magical trees.

    They’re going to give post-modern science a bad name.

    • Gary,

      Your verbal reconstruction (absent the pre-requisite pine cones) belongs in the Hall of Fame

      Well done!!!

  42. Oh, and hey, where are the comments from our favorite warmists claiming that the hokey stick is irrelevant to the climate debate and skeptics should stop talking about it?

    • The cabal of your favorite progressive warmists are probably gathered in a dingy library somewhere reading Mein Kampf. They will be back soon with some new material. Try to not to get too upset. They like it when you go all ballistic.

    • > Oh, and hey, where are the comments from our favorite warmists claiming that the hokey stick is irrelevant to the climate debate and skeptics should stop talking about it?

      Is that another invitation?

  43. Enter stage left the MJO onto the Equatorial Pacific El Nino 3.4 area. This happens every month or two. What have been the results? I am not interested in the speculations of climate science astrologers. What is the effect on El Nino/ La Nina? Can anyone tell me?

  44. Steve Fitzpatrick

    One interesting question that arises from this paper is: How many comically bad papers can S Rahmstorf publish is a single professional lifetime? Considering his many hilarious sea level rise papers (1 to 2 meters by 2100), one might imagine that editors would be cautious about accepting more of his tripe… but seems that is not the case. Maybe they are looking for tripe that adheres to their preferred narrative.

  45. I’m wondering if this paper is a Hail Mary, Throw-Science-Under-The-Bus attempt to prop up the hockey stick to beef up the case in court. See, Nature published my paper supported by the hockey stick!

  46. David L. Hagen

    Why appeal to bristle cones when we have a gaggle of rubber ducks to track currents?

  47. michael hart

    Whats up with the Atlantic?

    It is not wide enough or deep enough to encompass their egos. That is why they are dredging it for any and every excuse.

  48. In the meantime, the Little El Nino that couldn’t struggles on …

    http://home.comcast.net/~ewerme/wuwt/elninometer-current.gif

    • Jim, it is a bit dawdly, isn’t it?

      Something I don’t get is what an eventual El Nino is supposed to prove…except that El Ninos occur. We didn’t have Walker and those guys back in the early 1790s and late 1870s, but it’s a fair bet that the little male scamp was involved in the colossal monsoon failures and big heats of the past.

      We know more about 1997-8, 1982-3, the big double from 1940 to 1942, the double from 1913 to 1915 which got stronger, and the many other lesser El Ninos, some of which were more severe in effect than the stronger ones (2002-3 and the catastrophic “weak” of 1902-3 in Oz).

      Wouldn’t it be more peculiar if one went a long time without an El Nino? Warming of the central and eastern tropical Pacific is bound to occur, the semi-official rate being every three to eight years (for what it’s worth). Has happened, will happen. So what’s the big deal?

  49. Who knew Michael Mann was a natural comedian? What will he say next, global warming is causing marijuana users to become heroin addicts?

  50. stevenreincarnated

    It would be difficult to explain the changes in ocean heat content for the different ocean basins over the last century if you claim a reduction in the AMOC and this is especially true after 1970.

    http://www.aoml.noaa.gov/phod/docs/Lee_etal_2011_grl_amoc.pdf

  51. The same proxy data that eliminated the Roman and Medieval Warm period I suppose.

  52. It is interesting that this region of the North Atlantic has not warmed in a century according to GISTEMP.
    http://data.giss.nasa.gov/cgi-bin/gistemp/nmaps.cgi?sat=4&sst=3&type=anoms&mean_gen=0112&year1=1985&year2=2014&base1=1885&base2=1914&radius=1200&pol=rob
    And that the same region in 2014 has even taken a quick dive in temperature.
    http://data.giss.nasa.gov/cgi-bin/gistemp/nmaps.cgi?sat=4&sst=3&type=anoms&mean_gen=0112&year1=2014&year2=2014&base1=1885&base2=1914&radius=1200&pol=rob
    However, this region was also cold several times over the last few decades, but the cold anomalies only started in the 1970’s. The region was generally warmer in the early 20th century. There is a long term trend towards colder with decadal oscillations superimposed. Not sure what it means. Perhaps some long-term AMOC trend.

    • By the way, this agrees with what the Abstract said about trends over the 20th century and how they especially dip after 1970 with a partial recovery after 1990, and now another dip in 2014. GISTEMP shows it.

  53. harrytwinotter

    Judith Curry,

    how can you justify starting off you comments with this? You have not even addressed the article yet. And what is with your dislike of any study associated with Michael Mann? It is “poisoning the well” rhetorical argument.

    “Well, if there is anything I distrust more than climate model simulations of decadal to millennial scale ocean circulations and internal variability, it is Mannian proxy analysis of same. It seems like strip bark bristlecones and Tiljander sediments can tell us about Gulf Stream flow rates, as well as global temperatures. Remarkable.”

    • You should familiarise yourself with posts Judith has made in the past regarding Michael Mann’s work, including some of the name calling she has been subjected to by him. That would provide context that would explain the motivation for this statement.

      • harrytwinotter

        I am happy for you to do your own homework. It still does not explain the “poisoning the well” rhetoric.

    • Not sure what you are talking about there harry. Her comments are directly relevant to the paper, which claims that bristlecone pines, which are mostly from the western side of the US, and contaminated lake sediments in Finland, can be used to “reconstruct” circulation in the Atlantic. The paper fully deserves all the ridicule it is getting.

      • harrytwinotter

        It would be nice if Dr Curry would respond.

        If Dr Curry has issues with the proxies used in the reconstruction, some citations would be nice instead of insults. And less hostility – she is not very scientific in my opinion.

      • It would be nice if Dr Curry would respond.

        Why should she? Anybody familiar with the debate knows the answer, as you would if you bothered to research it before trying to waste her time.

        If Dr Curry has issues with the proxies used in the reconstruction, some citations would be nice instead of insults.

        See above. Or see here. Or here.

      • harry, this was a monstrous bluff by the Piltdown Mann, and why not. No other climate players have ever called his empty hand.
        =======================

      • harrytwinotter

        Using Denialist websites as citations doesn’t count.

      • Harry seems willfully ignorant. Shall we start him out with ‘Minnesotans for Global Warming’?
        ==============

      • Using Denialist websites as citations doesn’t count.

        Look at the citations there. Else you’re just a time-wasting troll.

  54. What is the whole content of R/M 2015? They generate a new index: AMOC= SSTspg – Tnh without any sufficent justification. There is so much literature that the SSH/SSTspg a l l o n e a good fingerprint for the AMOC. The subtraction of a HS-shape T-reconstruction of the NH (MM 2008) MUST lead to a downward HS-shape of the “Amoc index”. Just another “Mike’s Nature Trick”?

    • Remarkably audacious. Apparently self-destructive. Like he was double down dared to try this trick and was foolish enough to take the dare. The pathognomonic sign? It was he who dared himself.
      =======================

    • Yep. Dr. Mann is a statistical genius, at least using his statistical metrics.

  55. Pingback: Steve McIntyre: Reductio Ad Mannium | The Global Warming Policy Forum (GWPF)

  56. It is not my field but I would have thought the best way to estimate of historical Gulf Stream variability would be to look at the geostrophic effect on mean sea level measured along the North Carolina coast. Surely there must be a couple of centuries of good measured tidal data available which would make the use proxies irrelevant.

    • I was going to point out some of the problems with tidal gauges being used to estimate ocean currents but then I realized that Rahmstorf, et al., are using California bristlecone growth patterns to do the same thing. Your idea is infinitely better.

  57. What a nightmare. Unless this is comprehensively and publicly debunked any further cooling will catch in the public’s mind as being caused by some such anthropogenic means.

    Is that the gamble? It’s a desperation play, measured in units of solid cynicism.
    ==============

  58. Well, if there is anything I distrust more than climate model simulations of decadal to millennial scale ocean circulations and internal variability, it is Mannian proxy analysis of same.

    Do you care to put your scientific credibility and reputation, such as they are, behind this statement of distrust?

    • You can get anything you want in paleontology.
      ================

      • Kim

        This 1907 newspaper cutting reports that the gulf stream is cooling and slowing
        http://query.nytimes.com/mem/archive-free/pdf?_r=1&res=9903E2DF173EE233A25751C2A9669D946697D6CF

        This was prior to the sinking of the Titanic in 1912 from icebergs that were much farther south than usual, and was the precursor to the start of the 1917-1940 warm period in the arctic. Something similar seems to have happened around 1820 as well.

        The workings of the Gulf stream were described in this British Pathe News reel (linked below) which would have been shown in 1936-during this extreme warm period which bore many similarities to today. If we can forget recorded incidents that happened only within peoples lifetime, what hope is there of pointing out other warming incidents in the more distant past?

        http://www.britishpathe.com/record.php?id=10775

        This news reel also includes details of an American plan that would have diverted the Gulf Stream away from the UK!

        Look out for the graphics at the end which manages to mix Penguins and the North Pole

        tonyb

      • Those silly Yanks!

      • Another stake in the heart of the unprecedented nature of any of this. If Ben Franklin had sent up a few satellites and Thomas Jefferson had launched a few thousand Argo buoys, we would have a baseline and much of this hysteria about record warmth and record everything would be seen with a more sanguine view.

        Every week I see evidence that Mother Earth has been down this path before, even if we weren’t paying attention or couldn’t.

      • Interesting, tonyb. Very interesting.

        Everything is unprecedented if one ignores precedents. (Words which might be put on the Paris conference letterheads.)

    • A question you can’t answer, Bernard J, but I’ll direct it to you anyway. Would Rahmstorf and Mann put their scientific credibility and reputation on the line for this paper?

      Now a question for you. Would you put your scientific credibility and reputation on the line for this paper?

      Eagerly awaiting your answer.
      ================

    • Absolutely yes

    • Do you care to put your scientific credibility and reputation, such as they are, behind this statement of distrust?

      I didn’t think it was a scientist’s job to trust extraordinary claims, so I’m inclined to reject the notion that distrusting such claims could damage scientific credibility. Silly, I know…

  59. In a finding published on the same day as Professor Stefan Rahmstorf’s (et al.) paper made the news, an interesting article appeared from Britain’s National Oceanography center (in collaboration with NOAA and the University of Miami) which elaborated on the Smeed et al. paper “Observed decline of the Atlantic meridional overturning circulation
    2004–2012”, in fact they concluded that the observed decline was even faster … “However, the ocean sensors have detected that the AMOC is now declining faster than anticipated (Smeed et al. 2014), which could potentially have a long-term impact on Britain’s climate. “.

    This is a very serious finding indeed, completely independent of Professor Rahmstorf, Box, Mann et al., it may be argued or dismissed as variability, of course it is subject to debate like any other scientific paper of finding, but never the less continued monitoring is indeed essential.

    I hope an abrupt climate change early warning system will be set up as remarked about in “ABRUPT IMPACTS OF CLIMATE CHANGE A N T I C I P A T I N G S U R P R I S E” issued by the National Research Council, early on in 2014.

    Over time when a trend continues despite the ups and downs of decadal variability and cycles, then is the time to sit up and take note. Never before have we had so many excellent tools to monitor and measure, the picture we are building up on the behavior of Earth systems is becoming clearer and clearer. And in time all the debate and chatter will be resolved one way or another.

  60. Keep the gloves on , Judy and let others do the punching.
    This is a fantastic opportunity but as Alekhine said,
    When you see a good move, or target , look around, take your time, there is an even better move to find.
    There is a massive media/ govt push to get this agreement in 2015 and Obama is very good at pulling the right emotional strings.
    Pity he wants to save the world and is a believer.

  61. Pingback: Nytt lavmål for klimaortodoks forskning | Klimarealistene

  62. So is this paper relevant?

    Solar forcing of Holocene summer sea-surface temperatures in the northern North Atlantic by Hui Jiang, Raimund Muscheler, Svante Björck, Marit-Solveig Seidenkrantz, Jesper Olsen, Longbin Sha, Jesper Sjolte, Jón Eiríksson, Lihua Ran, Karen-Luise Knudsen, and Mads F. Knudsen Geology First published online February 2, 2015

    Mounting evidence from proxy records suggests that variations in solar activity have played a significant role in triggering past climate changes. However, the mechanisms for sun-climate links remain a topic of debate. Here we present a high-resolution summer sea-surface temperature (SST) record covering the past 9300 yr from a site located at the present-day boundary between polar and Atlantic surface-water masses. The record is age constrained via the identification of 15 independently dated tephra markers from terrestrial archives, circumventing marine reservoir age variability problems. Our results indicate a close link between solar activity and SSTs in the northern North Atlantic during the past 4000 yr; they suggest that the climate system in this area is more susceptible to the influence of solar variations during cool periods with less vigorous ocean circulation. Furthermore, the high-resolution SST record indicates that climate in the North Atlantic regions follows solar activity variations on multidecadal to centennial time scales.

    • Thx for this ref

      • Here’s another:

        Searching through Rahmstorf et al. for references to Solar Forcing, I find this:

        Our temperature reconstruction for the subpolar gyre differs from three estimates based on ocean sediment cores from the region[20,21].

        Note 20 is:

        Solar forcing of North Atlantic surface temperature and salinity over the past millennium by Moffa-Sanchez, P., Born, A., Hall, I. R., Thornalley, D. J. R. & Barker, S. Nature Geosci. 7, 275-278 (2014).

        There were several centennial-scale fluctuations in the climate
        and oceanography of the North Atlantic region over the
        past 1,000 years, including a period of relative cooling from
        about AD 1450 to 1850 known as the Little Ice Age1. These
        variations may be linked to changes in solar irradiance,
        amplified through feedbacks including the Atlantic meridional
        overturning circulation2. Changes in the return limb of the
        Atlantic meridional overturning circulation are reflected in
        water properties at the base of the mixed layer south
        of Iceland. Here we reconstruct thermocline temperature
        and salinity in this region from AD 818 to 1780 using
        paired 18O and Mg/Ca ratio measurements of foraminifer
        shells from a subdecadally resolved marine sediment core.
        The reconstructed centennial-scale variations in hydrography
        correlate with variability in total solar irradiance. We find a
        similar correlation in a simulation of climate over the past 1,000
        years.We infer that the hydrographic changes probably reflect
        variability in the strength of the subpolar gyre associated
        with changes in atmospheric circulation. Specifically, in the
        simulation, low solar irradiance promotes the development of
        frequent and persistent atmospheric blocking events, in which
        a quasi-stationary high-pressure system in the eastern North
        Atlantic modifies the flow of the westerly winds.We conclude
        that this process could have contributed to the consecutive cold
        winters documented in Europe during the Little Ice Age.

        Looking at their figure 2, I see an interesting century-scale trend:
        http://www.nature.com/ngeo/journal/v7/n4/images/ngeo2094-f2.jpg

    • The phase relationship between North Atlantic SST’s and the solar cycle reverses with alternate AMO modes:
      http://judithcurry.com/2015/03/25/whats-up-with-the-atlantic/#comment-686892

  63. You can see the effect on the Atlantic changing temp in the surface record
    http://www.science20.com/files/images/northern_continents.png
    https://curryja.files.wordpress.com/2015/03/slide13.png?w=500&h=375
    The first graph is the derivative of min and max temps for surface stations in Eurasia (as well as for the US), and you can see that during the cold amo phases, Min temp goes down (large negative values), but Max temps aren’t not really impacted.
    You can see the same for the African continent
    http://content.science20.com/files/images/Southern%20Continents_0.png.

    The 0F reference line is based on the starting date of the temp series, since I use the station itself for the baseline and not some cherry picked period, you can use whatever offset you’d like.

  64. NYT’s Andy Revkin from 5 years ago:

    “Here’s a brief update on the great heat-toting oceanic currents that at one time were thought to be at risk from human-driven warming of the climate. There’s been no slowdown at all through much of the past decade and probably none since the early 1990s, according to new work using methods developed by Joshua Willis at NASA’s Jet Propulsion Laboratory.

    “The prospect of a circulation slowdown driven by increasing flows of fresh water from melting ice sheets had built around early work of Wallace Broecker at Columbia University’s Lamont-Doherty Earth Observatory and culminated with the caricatured climate calamity in The Day After Tomorrow.

    “But through much of the last decade, Dr. Broecker adjusted his view as new information came to light, concluding that the “angry beast” of climate hidden in the Atlantic Ocean was a creature of the Earth’s cold periods and not likely to appear in warm times. In the 2007 reports from the Intergovernmental Panel on Climate Change, the prospects for a disruption of the currents were downgraded substantially from earlier reports.”

    http://dotearth.blogs.nytimes.com/2010/03/25/heat-toting-ocean-currents-chugging-along/?_r=0

  65. How can the hydrodynamics and thermodynamics of the situation not be a primary focus? The “patch” of cooler fluid is an open system with respect to mass and energy. It appears to be surrounded, completely, by fluid that is at a higher temperature than the temperature of the patch. The bulk motion tends, more or less, roughly from the southwest toward the northeast, and the figures indicate that warmer fluid both enters and leaves the region of the patch.

    Persistent gradients, in this case three-dimensional, absolutely require persistent driving potentials. Lack of driving potentials will ensure an approach to uniformity, or at least consistency of the distributions with the driving potentials.

  66. Jaime Jessop

    Relax people. Mann and Rahmstorf would have us all believe, that AMOC hit an ‘unprecedented’ low from 1975 to ’95 and that the Gulf Stream may go into catastrophic slowdown/shutdown in just a few decades. Rubbish.

    1.There has been no evidence of a decline in the Gulf Stream transport according to RAPID or earlier studies (Rossby, NASA). RAPID finds that the decline is due to other components of the flow. Even the Mann/Rahmstorf paper does not present evidence for a decline in the Gulf Stream – a fact which he VERY selectively chooses to make public.
    2. Mann’s historic reconstruction of AMOC inferred from SSTs cannot be taken seriously and it is this ONLY upon which he bases his claim that the 1975-95 decline in AMOC was ‘exceptional’.

    https://tallbloke.wordpress.com/2015/03/24/much-alarmist-ado-about-amoc-and-the-subpolar-gyre-collapsing/comment-page-1/#comment-99245

    https://tallbloke.wordpress.com/2015/03/24/much-alarmist-ado-about-amoc-and-the-subpolar-gyre-collapsing/comment-page-1/#comment-99266

    • harrytwinotter

      I have had a look at this stuff. The Rahmstorf et al study and Michael Mann are being misrepresented. This is known as a “straw man” argument.

      The Rahmstorf et al study is using a different spatial and temporal extent compared to the other studies. So they cannot be compared directly.

  67. Am I reading this right? Did Rahmstorf just admit that the Mann proxies are unreliable?

    “What is new is that we have used proxy reconstructions of large-scale surface temperature (Mann et al, 2009) previously published by one of us that extend back to 900 AD to estimate the circulation (AMOC) intensity over the entire last 1100 years. This shows that despite the substantial uncertainties in the proxy reconstruction,….. “

  68. “substantial uncertainties”

  69. Ulric’s reply to what I hade sent which I was hoping he would say. This means we are in very high agreement on this issue.

    ulriclyons | March 25, 2015 at 9:58 pm | Reply

    “The AMO then making the sea surface temperature deviate from that average but not controlling the ultimate average global sea surface temperature.”

    I cannot argue with that, and in fact I never have.

    • Salvatore Del Prete commented

      “The AMO then making the sea surface temperature deviate from that average but not controlling the ultimate average global sea surface temperature.”
      I cannot argue with that, and in fact I never have.

      I think these warm and cold spots in the oceans then impact the land masses downwind, when the Atlantic turns cold, the air blowing off of it will be that much colder than when the water is warm, these changes show up in the daily minimum surface station data, but it doesn’t seem to affect max temps.
      The oceans heat the water in the tropics, and then the rest of the planet acts like a chimney for the warm moist air that’s spun poleward. And when the warm spots in the oceans move, the path of the warmest air changes.

      Now, one of these big moves happened about the same time we started to measure a lot of surface of the planet, But since we didn’t even know about the PDO until after it was decided warming was from Co2, well we know what happened after that.

  70. AK thanks for the study which I think has much merit.

  71. Maybe it is the Washington Post that is slowing down its circulation with potentially dire consequences. I cirtainly think the blood flowing to the churnalist’s and his editor’s brains is slowing down.

  72. http://stateoftheocean.osmc.noaa.gov/sub/berm_lab_trans.php

    From the web-site oopc -The state of the ocean climate

    The last time the Bermuda -Labrador Basin Transport Index was updated was June 24 2009. Current value at that time was 62.0Mtons/sec

    This number being indicative of the strength of the Gulf Stream and North Atlantic Current.

    My question is why have they stopped updating this ? Since they have stopped, I would think data for this must no longer be present.

  73. Bernd Palmer

    In July 1999
 Stefan Rahmstorf claimed: “the Atlantic flow will probably slow down significantly in the coming decades – the simulations of the various institutions largely agree.”
    In July 2001 he said: “Cessation of the Gulf Stream is not likely”
    In 2007 he said: “Such fluctuations are completely normal”
    In Sep 2012 he said: “the risk of tipping of the North Atlantic Current is estimated increasingly pessimistically among experts.”
    Lifted from http://www.science-skeptical.de/klimawandel/und-taeglich-gruesst-das-murmeltier-stefan-rahmstorf-und-der-versiegende-golfstrom/0013666/ (German)

  74. David Springer

    http://www.bitsofscience.org/no-more-horror-winters-europe-winter-forecasts-4668/

    No more ‘horror winters’ for Europe – not for several years ahead – and indeed also not this year
    Posted on January 11, 2012 by Rolf Schuttenhelm
    Extremely cold winters for Europe persisting for several months are very rare. The last one to fit the definition occurred in 1963, almost half a century ago. Still many weather forecasters and media seem inclined (as again happened this year) to report on pending ‘horror winters’ – often without presenting much more than an animated air pressure chart to show how it would appear, and little or no published background information as to why it would happen.

    As such winters are extremely rare, but theoretically possible; one could argue there is a fair chance for such predictions to become reality. But, thanks to recent advances in climate science, no more.

    New insights* have led to improved predictability of a few key factors. Judging by these critical indicators at least the European winters of 2011-2012, 2012-2013, 2013-2014, 2014-2015 will have some normal climatic variation, but will not present persistent temperatures significantly below average – winters that keep the deep freeze on for several months.

    Therefore it seems it would be a good thing to help end the horror winter hype – for now – and probably for some time longer as well.

    AMOC forecast excludes European horror winters
    [*) Here our key references are to peer-reviewed scientific literature from 2011 and 2012 in the journals Nature Geoscience, Science and Nature Climate Change – with additional academic references as side notes.]

    Why no horror winters: (1) the not-stopping Gulf Stream, (2) the non-existent solar minimum, (3) the clearly observed rising temperature trend

    All factors that forecasters could – theoretically – base extreme cold winter scenarios on in fact point to the opposite direction, rather favouring (within normal variability range) mild and wet Atlantic winters – like the current European winter.

    Instead of a solar minimum [or even a proclaimed ‘new’ Maunder Minimum] ongoing NASA observations show we’ve already entered a normal new solar maximum that is forecast to stay until somewhere around 2017. This decreases the chance of high pressure blockades and the inflow of cold air from Arctic regions and Siberia.

    As can be read in our European winter outlook of November 10 2011 [which clearly turns out] the increased number of sunspots (as indicator of increased solar radiation) influences air patterns in the higher atmosphere. As a consequence [correlation shown for instance in Nature Geoscience publication by the UK Met Office Hadley Centre, Nov 2011] the Arctic Oscillation (AO) is (somewhat) more inclined towards a positive phase [which is why we forecast that during the 2011-2012 winter the US would experience fewer snowstorm outbreaks than in years before – as is indeed clearly the case] and (a stronger correlation) the North Atlantic Oscillation (NAO) also tends towards a positive phase.

    Europe therefore has a smaller chance for the formation of high pressure blockades over Scotland or Scandinavia – scenarios with respectively a direct influx of cold Arctic air and cold continental air, from the Russian Arctic or Siberia.

    –more at link above

  75. Bermuda-Labrador Basin Transport Index »
    24-JUN-2009

    62.0 Mtons/sec

    ±3.0 Mtons/sec

    The last update.

  76. Ulric says ,and I have to say the data supports his conclusions. I do not like to oppose the data.

    ulriclyons | March 25, 2015 at 2:54 pm | Reply

    “This strongly suggests that the weak overturning is not due to natural variability but rather a result of global warming.”

    Not possible it terms of forced warming. Increased forcing of the climate increases positive NAO/AO, while the low AMOC events recorded by RAPID-AMOC are all during negative NAO/AO periods.
    The most telling low AMOC events are in the summers of 2007 and 2012 when Arctic sea ice extent was at record lows. Plainly, negative NAO/AO periods cause low AMOC events, and is the direct means for warming surges of the AMO and Arctic Ocean.

  77. https://curryja.files.wordpress.com/2015/02/slide2.png

    As the data shows Europe did have a very cold winter during the recent very quiet solar lull. I think more of these winters will be coming if prolonged solar minimum conditions are the rule going forward.

  78. About the RAPID-AMOC Programme

    RAPID-AMOC (2014-2018) builds on the RAPID (2001-2007) and RAPID-WATCH (2008-2014) programmes and will extend the time series of the strength and structure of the Atlantic Meridional Overturning Circulation (AMOC) to 16 years.

    Observing and understanding the changes in the AMOC is critically important for identifying the mechanisms of decadal climate variability and change, and for interannual-to-decadal climate prediction. Sustained observations are also necessary for assessing the possibility of future abrupt change in the AMOC similar to those seen in palaeoclimate records.

    The RAPID array at 26°N is key to this effort. The array of instruments across the Atlantic from Morocco to Florida measure temperature, salinity and current velocities from the near surface to the sea floor. The array data is combined with observations from the Florida current and satellite measurements of surface winds to calculate the overturning circulation: northward flow in the upper layer, and southward flow in the deep ocean.

    The 26°N array was first deployed in April 2004 as part of the RAPID Programme. Measurements continued during RAPID-WATCH to yield a 10-year time series of continuous AMOC measurements. Both RAPID and RAPID-WATCH also included other research projects, which used ocean model simulations and analysis of RAPID and other observations to increase scientific understanding of the AMOC and its role in Earth’s climate.

    Observations from the array have already revolutionised understanding of AMOC variability and documented its variability on seasonal to interannual timescales. The first few years of observations, demonstrated the feasibility of AMOC measurement, provided new insights into the seasonal cycle, and allowed apparent trends in previous historical ‘snapshots’ to be seen in the context of natural variability.

    More recently, from autumn 2009 to spring 2010 the observations revealed a substantial weakening of the AMOC. A second weakening event occurred in late 2010. These events coincided with record low states of the North Atlantic Oscillation, and cold winter conditions over Europe. These anomalies would not have been detected without the presence of the array.

    The possible role of the AMOC anomalies in the cold winter of 2009/10 and 2010/11 is now a topic of active research. Anomalies of this magnitude are not seen in state-of-the-art climate models, calling into question the reliability of these models to serve as guides for future behaviour of the AMOC.

    The value of the array is likely to increase further as the length of the record increases, a more robust picture of the year-to-year variations of the AMOC develops, and perhaps further surprises emerge

  79. Jaime Jessop

    How did Mann, Rahmstorf et al construct their AMOC index? Simples – they used a climate model which told them where to look geographically for evidence of AMOC variability due to anthropogenic global warming. Turned out it was the sub-polar gyre so they merely subtracted the SSTs of this region from the NH as a whole to get their AMOC index. Whizzo.

    http://wattsupwiththat.com/2015/03/25/nasa-refutes-mann-and-rahmstorf-finds-atlantic-conveyor-belt-not-slowing/#comment-1891828

  80. Jamie could you look at my post on talkblokes site about my interpretation of the gyre from that diagram to see if I am correct or way off? Thanks.

  81. Jaime Jessop

    Will certainly think about that Salvatore and let you know, but I’m definitely no expert on such things!

  82. “Achilles Heel of the North Atlantic”

    “The North Atlantic is particularly important for global ocean circulation, and therefore for climate worldwide,” Reichler says. “In a region south of Greenland, which is called the downwelling region, water can get cold and salty enough – and thus dense enough – so the water starts sinking.”
    http://unews.utah.edu/news_releases/stratosphere-targets-deep-sea-to-shape-climate/

    http://www.nature.com/ngeo/journal/v5/n11/full/ngeo1586.html

  83. Which lends support to the NAO.

  84. Pingback: E’ tornato il giorno dopo domani | Climatemonitor

  85. ” From 1 April 2009 to 31 March 2010, the annually averaged MOC strength was just 12.8 Sv, representing a 30% decline. This downturn persisted from early 2009 to mid-2010. We show that the cause of the decline was not only an anomalous wind-driven event from Dec 2009–Mar 2010 but also a strengthening of the geostrophic flow. In particular, the southward flow in the top 1100 m intensified, while the deep southward return transport—particularly in the deepest layer from 3000–5000 m—weakened. This rebalancing of the transport from the deep overturning to the upper gyre has implications for the heat transported by the Atlantic.”
    http://onlinelibrary.wiley.com/doi/10.1029/2012GL052933/pdf

  86. Dan Pangburn

    It is trivially simple, using only existing data and rudimentary math to prove that CO2 has no significant effect on climate.

    See the proof and discover what actually does cause climate change (95% correlation since before 1900) at http://agwunveiled.blogspot.com

  87. Pingback: Global Warming, Uncle Commie and the Whole Nine Yards | evilincandescentbulb

  88. Dan Pangburn

    Sal – Thanks for the link. I wonder why this isn’t getting more play. Combined with the proof that CO2 is not a forcing leaves no wiggle room.

    I wonder how much the average global temperature will need to decline for the ‘consensus’ to recognize that they made a mistake.

  89. Good questions Dan.

    I hate to say it but I will and that is AGW theory seems to ignore the data.

    Let me answer my own question . Probably because the data proves them to be wrong each and every time.

  90. Pingback: Georgia Tech Climatologist Curry: “No Sign Of Slowdown” In AMOC…Sees Atlantic “Arctic Sea Ice Recovery”, Hints Of Greenland Cooling | wchildblog

  91. Much talk about fighting warming that does not exist, thanks to idiotic official policy based on lies and deceptions. The first lie is that there is warming now when in fact there has been none for the last 18 years. And that despite constantly increasing carbon dioxide in the air. According to the predictions of the greenhouse theory used by the IPCC this should cause warming by the greenhouse effect but it does not do that. A scientific theory that makes false predictions is considered false and belongs in the waste basket of history. That theory is history but if it had to perish twice, there is also a second hiatus, kept secret by the coordinated might of GISS, HadCRUT and NCDC. I am talking of the cessation of warming in the eighties and nineties that also lasted 18 years, from 1979 to 1997. Exactly the same thing happened with that hiatus – atmospheric carbon dioxide increased while no warming took place. I discovered it while doing research for my book “What Warming? Satellite view of global temperature change (2010).” and even put a warming about it into the preface of the book. That is the second big deception of the global warming gang, But nothing happened for five years while these notable rulers of the temperature waves kept showing the false temperature record. It even got incorporated into AR5 and makes the AR5 output false. It is very noticeable in the global warming curve of theirs that shows a steady upward slope from the seventies and eighties on that goes by the name of “late twentieth century warming.” The falsified segment should be replaced by a rightward horizontal indent of eighteen years in the eighties and nineties that will completely disrupt the appearance of the smooth upward progression of temperature they wish to represent. There is of course an explanation for why the addition of carbon dioxide to the atmosphere does not cause warming. What explains it is the Miskolczi greenhouse theory or MGT. It came out in 2007 and was promptly blacklisted by the global warming gang because of its predictions. MGT tells it just like it is – addition pf carbon dioxide does not warm the air. If true, this kills the greenhouse theory of global warming, the alleged cause of AGW. Don’t forget that the IPCC was established specifically to study human contribution to to global warming. With AGW gone there is no human contribution to warming and no reason to keep IPCC in existence. The difference between the Arrhenius greenhouse theorem of IPCC and that of the Miskoöczi theory is that MGT can handle several GH gases simultaneously while Arrhenius can handle only none – carbon dioxide. The assertion by IPCC that water vapor in the air will triple the greenhouse effect from the Arrhenius theory must be added as a separate hypothesis and has no scientific value. Water vapor and carbon dioxide are the two major greenhouse gases in the atmosphere. According to MGT they form a joint optimum absorption window in the infrared. Its optical thickness is 1.87, determined by Miskolczi from first principles. If you now add carbon dioxide to the atmosphere it will start to absorb in the IR, just as the Arrhenius theory says. But this will increase the optical thickness. And as soon as this happens, water vapor will start to diminish, rain out, and the original optical thickness is restored. The added carbon dioxide will of course keep absorbing but the reduction of water vapor keeps total absorption constant and no warming is possible. The result is no greenhouse effect, hence no anthropogenic global warming or AGW. Absence of the greenhouse effect also means absence of the runaway greenhouse effect that James Hansen used to warn us who keep burning fossil fuels. According to AGW carbon dioxide in the air does not warm the air and is not responsible for any global warming, past, present, or future. Trying to stop warming by emission controls is irresponsible action by advocates and politicians who are ignorant of real climate science.

  92. Pingback: Weekly Climate and Energy News Roundup #174 | Watts Up With That?

  93. Pingback: Gulf Stream Slowing – just another unfounded climate scare | wryheat

  94. Pingback: Week in review – science and technology edition | Climate Etc.

  95. Pingback: Week in review – science and technology edition | Enjeux énergies et environnement

  96. Pingback: Cooling in North Atlantic Defies Global Warming | oceanbites