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The Original Hockey Stick: Mann Hockey Stick (Mann, Bradely and Hughes (1998))

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Mann selected only ONE Siberian yamal tree sample from a major series collected by Russian scientists. He also chose bristlecone pines (known to have been unsuitable for paleoclimatological studies) and heavily weighted their hockey stickiness in his statistical wizardry.

Need we mention his use of the Tiljander Lake (Finland) series, 1) from a section that had been contaminated and disturbed by industry and settlement of the area and, 2) improperly used it upside down to enhance the hockey stick plot despite being told by the scientist who originally created this series!
. Michael Mann’s 2008 Reconstruction – Watts Up With That? By Andy May In my last post, it was suggested that Michael Mann’s 2008 reconstruction (Mann, et al., 2008) was similar to Moberg’s 2005 (Moberg, Sonechkin, Holmgren, Datsenko, & Karlen, 2005) and Christiansen’s 2011/2012 reconstructions.

Michael Mann’s 2008 Reconstruction – Watts Up With That?

Hockey Stick Groundhog Day. Some ancient history Fifteen to twenty years ago, Michael Mann and colleagues wrote a few papers claiming that current warming was unprecedented over the last 600 to 2000 years.

Hockey Stick Groundhog Day

Other climate scientists described Mann’s work variously as crap, pathetic, sloppy, and crap. These papers caught the interest of Stephen McIntyre and this led to the creation of his Climate Audit blog and the publication of papers pointing out the flaws in these hockey stick reconstructions. In particular, Mcintyre and his co-author Ross McKitrick showed that the method used by Mann and colleagues shifted the data in such a way that any data sets that showed an upward trend in the 20th century would receive a stronger weighting in the final reconstruction. With this method, generation of a hockey-stick shape in the temperature reconstruction was virtually guaranteed, which M&M demonstrated by feeding in random numbers to the method. As climate scientist Rob Wilson put it in an email, Ouch.

Two new papers Like this: Michael Mann "Hockey Stick" Update: Now Definitively Established To Be Fraud. The bright pink plus the dotted line in between the two pink portions shows one of the data series used in the construction of the Hockey Stick graph; but the pink portions were deleted when the graph was presented.

Michael Mann "Hockey Stick" Update: Now Definitively Established To Be Fraud

Obviously, inclusion of these pink portions would have thrown off the nice, flat "shaft" of the stick, while also revealing that this particular group of "proxies" had totally failed at matching the twentieth century rise in temperatures derived from the thermometer record, thus undermining the whole idea that these were valid proxies at all. In other words, Mann et al. had truncated inconvenient data that failed to match the narrative they wanted to present. Most would call this kind of data truncation a clearcut instance of "scientific fraud. " Michael Mann's quantum climate pseudoscience. Michael Mann is the most notorious fraudster in the global warming scam.

Michael Mann's quantum climate pseudoscience

He was the key man in the team that constructed the "hockey stick graph" of temperatures in the recent millennium or two. This is the politically correct version of the original video "Hide the Decline" that roughly describes what Mann did. Given it's just a song, the explanation is very accurate but I still prefer more accurate explanations than songs. Study reveals that Mann's Bristlecone pine trees may not be good "treemometers" after all. Dr.

Study reveals that Mann's Bristlecone pine trees may not be good "treemometers" after all

Michael Mann used tree ring core samples from Bristlecone pines in the Western United states as one of the most heavily weighted proxies used to make his infamous “hockey stick” Now it seems that even though temperature in these areas has been rising, the Bristlecones aren’t responding to it by increasing their range, and other tree species are jumping ahead in the same area. I pointed out some years ago that Mann didn’t seem to be aware of Liebigs Law of the Minimum which regulates plant growth. See also Bristlecone Pines: Treemometers or rain gauges ? Earth’s oldest trees in climate-induced race up the tree line.

McIntyre: The deleted data from the “Hide the Decline” trick. By Steve McIntyre from his site.

McIntyre: The deleted data from the “Hide the Decline” trick

For the very first time, the Climategate Letters “archived” the deleted portion of the Briffa MXD reconstruction of “Hide the Decline” fame – see here. Gavin Schmidt claimed that the decline had been “hidden in plain sight” (see here. ). This isn’t true. Michael Mann Used Well Known Deceitful Statistics to Create the Hockey Stick – CO2 is Life. H/t Commenter Sunsettommy.

Michael Mann Used Well Known Deceitful Statistics to Create the Hockey Stick – CO2 is Life

A Point Resolved in the Hockey Stick Wars. Sometimes seemingly small disputes can tell you a lot.

A Point Resolved in the Hockey Stick Wars

One of a what seems to be a bazillion points of dispute between Steve McIntyre and Michael Mann involves a claim by McIntyre that Mann mistakenly used a number of paleo-climate proxies upside-down. Mann replied by outright rejecting the claim: The claim that ‘‘upside down’’ data were used is bizarre. One of the challenges for observers of disputes about climate science is that they are often complicated, technical and nearly impossible to resolve without becoming an expert yourself. So generally people resolve them based on factors other than logic and data. Evidence pointing to a resolution of the dispute can be found in a newly released correction to a paper by the lead author (Kaufman) that was also claimed to have used proxy data upside-down.

Michael Mann’s special purpose Hockey Stick filter has been exposed. Jean S writes at Climate Audit: As most readers are aware, and stated in my post few hours after (ClimateGate) CG broke out, Mike’s Nature trick was first uncovered by UC here.

Michael Mann’s special purpose Hockey Stick filter has been exposed

He was able to replicate (visually perfectly) the smooths of MBH9x thereby showing that the smooths involved padding with the instrumental data. The filter used by UC was the zero-phase Butterworth filter (an IIR filter), which has been Mann’s favourite since at least 2003. McKitrick: What the Hockey Stick Debate is About? « Climate Audit. Ross McKitrick has an engaging presentation of the Hockey Stick Debate presented on April 4, 2005.

McKitrick: What the Hockey Stick Debate is About? « Climate Audit

Here is the abstract: The hockey stick debate is about two things. At a technical level it concerns a well-known study that characterized the state of the Earth’s climate over the past thousand years and seemed to prove a recent and unprecedented global warming. On ‘denying’ Hockey Sticks, USHCN data, and all that – part 1. Part 2 is now online here. One of the things I am often accused of is “denying” the Mann hockey stick. And, by extension, the Romm Hockey stick that Mann seems to embrace with equal fervor. While I don’t “deny” these things exist, I do dispute their validity as presented, and I’m not alone in that thinking.

As many of you know Steve McIntyre and Ross McKitrick, plus many others have extensively debunked statistics that went into the Mann hockey stick showing where errors were made, or in some cases known and simply ignored because it helped “the cause”. On ‘denying’ Hockey Sticks, USHCN data, and all that – part 2. In part one of this essay which you can see here, I got quite a lot of feedback on both sides of the climate debate. Some people thought that I was spot on with criticisms while others thought I had sold my soul to the devil of climate change. It is an interesting life when I am accused of being in cahoots with both “big oil” and “big climate” at the same time. Reflections on Mark Steyn’s ‘A Disgrace to the Profession’ about Dr. Michael Mann. Given what happened today in live testimony before the House Science Commiittee where Dr.

Mann was testifying, this review seems germane and timely. Guest essay by Rick Wallace Mark Steyn’s A Disgrace to the Profession is a compilation of scientific commentary on Michael Mann and his work and is a valuable antidote to the idea that questioning or criticizing this particular researcher is an overt admission of ignorance, let alone an “attack on science”. What I will argue in this essay is that Steyn has done serious students of the AGW hysteria an even greater service. A detailed review of the book: ‘A Disgrace to the Profession’, by Mark Steyn.

Book review by Andy May Mark Steyn has written a wonderful new book on Dr. Michael Mann’s hockey stick and the controversy surrounding it. It is difficult to overstate the significance or impact of Mann’s Hockey Stick (Mann, Bradley, Hughes (23 April 1998), “Global-scale temperature patterns and climate forcing over the past six centuries” (PDF), Nature 392 (6678): 779–787, Figure 5, the paper is often abbreviated as “MBH”).

IPCC throws Mann’s Hockey Stick under the bus? While the media circulates the talking points pre-release “leaked draft” of IPCC’s AR5 amongst themselves, there are a few nuggets of interest coming out here and there we can write about. One such nugget is contained in a series of bullet points on the Washington Post Capital Weather Gang in an article by Jason Samenow: 7) The 30 years from 1983-2012 was very likely the warmest 30-year period of the last 800 years. That is an interesting statement, not so much for what it says, but for what it doesn’t say. FLASHBACK: Twenty years ago today, the infamous “hockey stick” was published in Nature.

Twenty years ago today: The infamous “hockey stick” graph that crystalized global warming and ignited the climate wars was published, and became known as MBH98. The science in it was so bad, it is credited with spawning the modern climate skeptic movement. Michael E. Climategate 2 email – Rob Wilson replicates McIntyre & McKitrick – produces hockey sticks out of noise. 20 Years Later, The ‘Hockey Stick’ Graph Behind Waves Of Climate Alarmism Is Still In Dispute. It was 20 years ago, climate scientist Michael Mann published his famous “hockey stick” graph that he says “galvanized climate action” by showing unprecedented global warming. Original “hockey stick” temperature graph in Nature, 1998. How To Tell Who's Lying To You: Climate Science Edition — Manhattan Contrarian. Make your own Michael Mann hockey stick at home. Tim Barnett on the hockey stick- “statistics were suspect”–the rest of the team knew of problems with Mann’s reconstruction. First look: ‘Hit on the head with a hockey stick’ – some selected emails from the recent NOAA FOIA release 2 years later.

Readers may recall this yesterday: NOAA releases tranche of FOIA documents – 2 years later. I have a few to share from CEI now. Here’s one email, right after Climategate1, that is uproariously funny, given NRO’s response to Dr. Michael Mann today. Heh. Here’s that email thread plus others as PDF files. NOAA emails reax to ClimateGate How IPCC sausage is made in 2007: IPCC_Sausage_factory The Team is unhappy with Andrew Revkins post CG1 questions on IPCC, one refuses to look at his blog anymore. Alarmists not happy with Revkin for noting IPCC probs Let’s meet with the President-elect. See comments about the role science must play to help BHO to get cap and trade passed. Mann’s Hockey Stick, Climategate, and FOI – in a nutshell. Image via Wikipedia.