Two more independent studies back the Hockey Stick: Recent global warming is unprecedented in magnitude and speed and cause

There are now more studies that show recent warming is unprecedented —  in magnitude and speed and cause — than you can shake a stick at!

As with a pride of lions, and a conspiracy of disinformers [or is that a delusion of disinformers?], perhaps the grouping should get its own name, like “a team of hockey sticks” (see “The Curious Case of the Hockey Stick that Didn’t Disappear“).

  1. GRL:  “We conclude that the 20th century warming of the incoming intermediate North Atlantic water has had no equivalent during the last thousand years.
  2. JGR:  “The last decades of the past millennium are characterized again by warm temperatures that seem to be unprecedented in the context of the last 1600 years.” [figure below]

Hockey SA small

Reconstructed tropical South American temperature anomalies (normalized to the 1961-1990AD average) for the last ˆ¼1600 years (red curve, smoothed with a 39″year Gaussian filter). The shaded region envelops the ±2s uncertainty as derived from the validation period. Poor core quality precluded any chemical analysis for the time interval between 1580 and 1640 AD.

Yes, the 39″year Gaussian filter appears to wipe out over half of the warming since 1950 as this NASA chart makes clear:

As WAG notes, within a few decades, nobody is going to be talking about hockey sticks, they will be talking about right angles (or hockey skates):

The rate of human-driven warming in the last century has exceeded the rate of the underlying natural trend by more than a factor of 10, possibly much more.  And warming this century on our current path of unrestricted greenhouse gas emissions is projected to cause a rate of warming that is another factor of 5 or more greater than that of the last century.  We are punching the climate beast “” and she ain’t happy about it!

What’s amusing is that Anthony Watts actually focuses on this Journal of Geophysical Research paper, “Ammonium concentration in ice cores: A new proxy for regional temperature reconstruction?” in his post, “Study: Ammonium as ice core proxy shows strong Medieval Warm Period in the tropics.”

For the record, even a moderate MWP (even if it were global, which remains unproven) does nothing whatsoever to undermine our understanding of human-caused global warming.  The temperature trend in the past millennium prior to about 1850 is well explained in the scientific literature as primarily due to changes in the solar forcing along with the effect of volcanoes, whereas the recent rise in temperature has been driven primarily “” if not almost entirely “” by human activity (see Scientist: “Our conclusions were misinterpreted” by Inhofe, CO2 “” but not the sun “” “is significantly correlated” with temperature since 1850 and a post to be named later).

The Geophysical Research Letters paper, “Twentieth century warming in deep waters of the Gulf of St. Lawrence: A unique feature of the last millennium” concludes:

… irrespective of the precise mechanisms responsible for the temperature variations reconstructed from core MD99″2220, it is unquestionable that the last century has been marked there by a warming trend having no equivalent over the last millennium.

For those keeping score at home, here are a few more members of the team of hockey sticks (although the last two aren’t actually independent, as discussed here).

From Human-caused Arctic warming overtakes 2,000 years of natural cooling, “seminal” study finds (2009):


From Unprecedented warming in Lake Tanganyika and its impact on humanity (2010):

Lake Tanganyika lake surface temperature

From Sorry disinformers, hockey stick gets longer, stronger: Earth hotter now than in past 2,000 years (2008)


And from McShane and Wyner (2010):


And yes, McShane and Wyner has been debunked in the blogosphere — see I went to a statistician fight and a hockey stick broke out — and is currently being eviscerated in the original journal itself.  More on that shortly.


32 Responses to Two more independent studies back the Hockey Stick: Recent global warming is unprecedented in magnitude and speed and cause

  1. If we had the technology to remove CO2 and equivalents from the atmosphere, how fast do we have to remove it, and how long will it take until we see the climate cool?

  2. mike roddy says:

    Thanks for the update. This is a good addition to the Realclimate piece from last year:

    The deniers have long tried to jump on the hockey stick, since it’s easily comprehensible to casual readers or viewers of Gore’s movie. The time may be ripe for a detailed review of all of these denier attacks on the subject, from McIntyre, Watts, Wegman, and now McShane and Wyner.
    Fossil fuel funded think tanks and some gullible members of the media have succeeded in creating doubt about this key data, based on opinion polls.

    It’s pretty easy to debunk their claims, since they have no substance, but this needs to go to the next level. The American public needs to see in clear language that they have been lied to, and that the perpetrators have relationships with those who are trying to sell us more oil and coal. Brief bios of the usual charlatans should be included.

    This should be a journalist’s project for a major media outlet, even if it ends up being one with limited circulation, such as the New Yorker. It won’t be news to Climate Progress readers, but someone from the choir needs to sing it loud to the general public. If the article ends up being sold to a small highbrow publication, there should be a coordinated PR campaign to see that major media publications mention it with links.

    Things are getting very serious. It’s time to insist on this story being told to everyone, and not assume that the enlightened ones among us are just another niche interest group.

  3. MarkB says:

    “The Team” just keeps getting bigger. They must all be the cronies of the evil Dr. Mann.

  4. MapleLeaf says:


    Thanks for covering this. You say “For the record, even a moderate MWP (even if it were global, which remains unproven) does nothing whatsoever to undermine our understanding of human-caused global warming.”

    That is quite correct, I might also add that if the MWP were indeed global, then it would point to a climate sensitivity which is on the high end of the current range. The reason being that only very weak forcing anomaly would have resulted in discernible warming. So the contrarians should be very careful what they wish for.

    This is obsession with the MWP by ‘skeptics’ is yet another example of the contrary nature of their arguments. That is,arguing that the MWP was global (i.e., high climate sensitivity), yet claiming that climate sensitivity is low.

  5. Bob Doublin says:

    I vote for “a delusion of deniers” That is so cool! I am definitely stealing it.

  6. Bob Doublin says:

    OOps,I loved it so much I forgot it was”a delusion of disinformers” That’s even better.

    [JR: Either one works.]

  7. Colorado Bob says:

    How Hillary Clinton’s clean stoves will help African women

    Poorly ventilated small fires are claiming millions of lives – as wood for them wrecks the environment

  8. Lou Grinzo says:

    mike roddy says:

    “The deniers have long tried to jump on the hockey stick, since it’s easily comprehensible to casual readers or viewers of Gore’s movie. The time may be ripe for a detailed review of all of these denier attacks on the subject, from McIntyre, Watts, Wegman, and now McShane and Wyner.”

    Bingo! On both points.

    I think it’s a sign of how clueless people on “our” side of this non-debate are when they ask incredulously why the deniers are so obsessed with the hockey stick when so many other pieces of evidence are lying around for them to, well, lie about. Mike nails the reason: Show one of the HS graphs to a mainstream consumer and (much more important) voter who isn’t currently engaged on climate issues, and s/he will instantly “get it”. It reduces the chapter-long explanation to an extremely effective bumper sticker level of brevity, which therefore makes it a very powerful teaching tool. That Must Not Be Tolerated, so the deniers viciously attack the HS itself and everyone who supports it.

    The fact that the deniers don’t have a leg to stand on is irrelevant; when has the truth ever kept them from leaping to their ideology-prescribed conclusion?

  9. homunq says:

    “Delusion of deniers” has a great ring, but perhaps we should be calling them “a front-group of polluters”? Like Soviet-Stalinist front groups during the cold war, they are an enemy within, intent on undermining democracy in service of the evil ideology of a few megalomaniacs. Like those groups, there are a few honest dupes mixed in with the schemers on the take. (But the “communist” label covered above-board Marxists and other honest leftists as well as effectively-foreign-agent Stalinists.) Unlike cold-war US Stalinists, deniers have real power.

    (In fact, of course the various domestic fascists, Monroe-doctrine imperialists, and unionbusters who joined under the banner of anticommunism did far more damage than any US Stalinists; but that doesn’t mean that the latter were innocuous.)

    OK, forget Stalin. The point is, “polluter front-group” or “polluter front-man” focuses the attention and the debate where it should be, on the source of support; not on made-up debates about science. This may even be a partial antidote for the pathetic “cover the debate” press corps; it gives them a Story to cover which is not on the polluters’ terms.

  10. homunq says:

    “polluter fellow-travelers”. Or, if you want one from the other side, “running-dogs”.

  11. homunq says:

    Note: my comment 10 above is a postscript to comment 9 which is still in moderation.

  12. John McManus says:

    Great idea Lou. I have never had a bumper sticker, but I would display one that was just a hockey stick.

    I live far enough away from Tiny Witt that I won’t be hurt when his head explodes.

  13. Rob Honeycutt says:

    The irony is, each time one of these studies comes through – the one’s that Watts and co trumpet as more proof of the MWP – it is also a strong case for higher climate sensitivity.

  14. MapleLeaf says:

    Mike @2,

    “Things are getting very serious. It’s time to insist on this story being told to everyone,”

    Maybe Joe could pull some strings?

  15. Colorado Bob says:

    ‘Chemical nonsense’: Leading scientists refute Lord Monckton’s attack on climate science

    A coalition of leading climate scientists yesterday filed a 48-page document to the US Congress refuting an attack on climate science made earlier this year by the Ukip deputy leader, Lord Christopher Monckton.

    The detailed rebuttal addresses nine key scientific claims made by Monckton, a prominent climate sceptic, to a house select committee hearing in May. It includes the responses of 21 climate scientists who variously conclude that Monckton’s assertions are “very misleading”, “profoundly wrong”, “simply false”, “chemical nonsense”, and “cannot be supported by climate physics”.

  16. paulm says:

    Its slowly sinking in…
    “The nightmare scenario for industry losses is a Miami hit, closely followed by a New York hurricane,” Young said in a telephone interview from Washington. “Gulf oil is a huge issue for the insurance industry. There’s a feeling that if something big happens, there’s going to be some hard times.”

  17. paulm says:

    That right angle graph needs to be promoted more everywhere….!

  18. mike roddy says:

    Lou Grinzo and Maple Leaf- you’re two of my favorite commenters, and thanks for supporting my idea. Existing debunkings of McIntyre and Wegman have been a little too abstruse for general readers. This mission calls for simple language, with a little humor thrown in.

    It would take about two months of research and writing to do this right. I’d be willing to do it on assignment, but can’t afford to do it on spec. Maybe Joe has ideas about how to proceed here.

  19. Tom Mazanec says:

    Well, we are well over the Medieval Maximum. How do we compare to the Holocene climatic optimum? The Sangamon-Eemian Interglacial? The Pliocene (after the Isthmus of Panama formed, since that probably influenced ocean currents)? Although by the late Pliocene the species were probably different, if not the genera, so I don’t know how good an analogue that would be for how zoological/botanical distributions might be in a warmed world.

  20. Colorado Bob says:

    After the discovery of more dead fish in Plaquemines parish, the third in a week, parish president Billy Nungesser is demanding federal involvement when it comes to testing the waters in the parish hit by heavy oil.

    The latest fish kill was spotted in the southern end of the parish in Bayou Robinson.

    “We’ve never seen so many species floating in so many different areas.

  21. MapleLeaf says:

    Hi Mike @16,

    You are welcome, and thank you.

    I sincerely hope that your project or one similar to it will get off the ground. This is when I wish that I had a million dollars and could finance such a valuable projects ….

  22. pete best says:

    We all know reading here that ACC/AGW is real, its just what to do about it which is also why we read here. Unfortunately the USA has the money, the technology, the efficiency capability to cut emissions but does it have the will power culturally, the political power and the belief/science to do it?

    Personally I to some degree presently agree with Geroge Monbiot’s article in the Guardian (UK broadsheet) –
    in which he states that presently the process of agreeing carbon cuts in whatever form they take will not be agreed upon. The world will talk but it will not agree for another two years at least. Its just not ready and too many people dont believe it is hapenning I guess.

  23. cervantes says:

    OT, but I don’t ever remember a hurricane – not the remnants, but an actual living hurricane — off the coast of Greenland. And it’s projected to strike Baffin Island as a tropical storm. Is that as weird as I think it is?

  24. NeilT says:

    I hope the Polar Explorer team is on the ball. The last reported position at 14:15 CET was 73.10202,-89.92892. It’s going to be pretty rough for them. I guess they didn’t allow for a “tropical storm” whilst making their way through the icebergs……..

  25. MapleLeaf says:

    Neil and Cervantes,

    At least one post hurricane storm has made it that far north in recent years. That said, Jeff Masters would have a much better idea and be able to place this event in the appropriate context.

  26. catman306 says:

    A hurricane in Greenland will probably be adding many inches of warm rainfall to the ice cap. You can think of it as a heat source. Damn! Someone’s ice melt model just took a severe hit. But it’s not possible to model for the unknown.

  27. cervantes says:

    This isn’t a post-hurricane storm. Igor is still a hurricane.

  28. MapleLeaf says:

    Hi cervantes,

    Re #27. You are correct, as of 18 UTC today Igor was still a cat 1 hurricane– it is expected to become post tropical later this afternoon. In my comment at 25 I was referring to you saying “but an actual living hurricane — off the coast of Greenland”. At that point Igor will most likely be a post-tropical storm.

    That said, it is forecast to be a post tropical storm with hurricane force winds off Greenland for goodness’ sakes. Wow.

  29. Colorado Bob says:

    an actual living hurricane — off the coast of Greenland

    Heat moving from warm to cold.

  30. Jim says:

    Its plainly obvious that between 1580 and 1640 the temps went through the roof and this has been explained away by poor core quality. We will call this the “Mayan Maximum”. Careful reading of ancient Mayan hyreglyphics by “Lord Mungtin” will undoubtedly bring this to light.

  31. CruelIrony says:

    Thanks for the this!. George Monbiot has a great piece on gullible skeptics:

    It appears that the MWP is clearly a real event and looking ever more likely to be global. This suggests to me that some natural (global) event occured at this time yet I haven’t seen any explanation/speculation of likely causes.

    Could someone point me in the right direction?


  32. apeescape says:

    Gavin et al. has a rebuttal to the McShane and Wyner paper.