New Mann-made global warming study is ‘scientifically valueless paper’

Reason4Reason, Wikimedia CC-SA 3.0A new study published this week by climate activist Michael Mann is coming under scrutiny from other climate experts because it claims any warming since 1950 is 100 percent man-made and that since 2000, 13 of those years had record-breaking temps. But Mann’s study does not adequately account for natural variability such as ocean oscillations, which have been shown to dramatically affect the climate.

Published in Nature Scientific Reports and co-authored by an environmental group, it shows there have been a string of record-breaking ‘hot years since 2000’ that Mann says is ‘almost certainly a sign of man-made global warming.’

The so-called hottest years also fall within the global warming hiatus, a time frame lasting nearly 19 years before a strong El Niño in 2015 raised temps worldwide. Both the UN’s Intergovernmental Panel on Climate Change (IPCC) and leading climate scientists have acknowledged this hiatus. That’s because the satellite record dataset shows no statistical increase in warming as predicted by global warming theory. Even land- and sea-based temperature stations show much less warming than predicted by climate models.

The study, which relied primarily on computer simulations and dubbed itself “semi-empirical,” indicated it “estimated the chance of the record run – with up to 13 of the 15 warmest years all from 2000 to 2014 – was between one in 770 and one in 10,000 if the series were random with no human influence.” Mann, a professor of meteorology at Pennsylvania State University, told Reuters that “climate change is real, human caused and no longer subtle.” He set out to prove what he believes to be fact.

One of the study’s co-authors, Stefan Rahmstorf of the Potsdam Institute of Climate Impact, said in a statement, “Natural climate variations just can’t explain the observed recent global heat records, but man-made global warming can.” The scientists tried to account for factors including “heat from one year spilling into the next.” Except “temperatures in many years are almost identical, making it hard to rank their heat with confidence.”

Mann, who is an advocate of catastrophic man-made global warming, has done paid speaking engagements, environmental activist videos, lectures, written books (Dire Predictions, The Hockey Stick and the Climate Wars), numerous articles, and more. He has called anyone that doesn’t believe in the catastrophic man-made global warming narrative ‘anti-science.’ He also said in legal court documents (page 2, paragraph 2) that he had been “awarded the Nobel Peace Prize.” He wasn’t.

Nic Lewis, a leading climate scientist in the UK, writes in an email that Mann’s latest study is a “scientifically valueless paper even if it is 100 percent correct.” That’s because there is “nothing in this study that considers the probability of the high, recently recorded temperatures having arisen in the case where there is an anthropogenic [man-made] component, but it is less strong than simulated by the CMIP5 models, e.g. because they are too sensitive.” He also says the “analyses” they cite in the study’s intro is an “editorial comment” by Michael Mann.

First, Mann et al had to devise a simulation using computer models to create the following scenario: what observed temperature records would have been with and without human influence. That may explain why Mann recently tried to discredit the satellite dataset in an environmental group’s video, as it shows no statistical global warming for the past 18 years 8 months. And 2015, which wasn’t included in this study, was as warm as 1998 due to a naturally occurring El Niño event and the Pacific blob.

“The analysis of Mann et al glosses over three major disputes in climate research, ” Judith Curry, a climate scientist and Georgia Tech professor, writes in an email. “These disputes are errors and uncertainty in the temperature record” and “reconciling the surface temperature record (which shows some warming in the recent decades) against the global satellite record (which shows essentially no warming for the past 18 years).”

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  • Avatar

    David Lewis

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    A quote from the article, “The study, which relied primarily on computer simulations.”

    So this study is using flawed computer models to support an agenda based on the flawed IPCC computer climate models. This is typical of the alarmist. They use simulations over real world data because things like the pesky satellite data don’t support their political agenda.

    Reply

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    Chris

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    So, let me get this straight Mann…natural variation can’t explain how temperatures at the far end of an upward trend that has naturally been increasing since the maunder minimum and for the last 18 years hasn’t warmed at all cannot explain record heat years?
    Sorry, but that’s completely lacking in logic.
    Of course temperatures at the top of an incline are going to set records, you might as well take temperatures just after the last ice age and say natural variation cannot explain these rising temperatures.

    The question is why the models don’t reflect the low climate sensitivity and why temperatures have not risen in 18 years.

    Nic Lewis is panicking and trying to pull it back by claiming there is still a significant man made influence but less so as the alarmists are wont to do now that the public are cottoning on to the mismatch between models and observations.

    Reply

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    Amber

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    As they say, the fewer the facts the stronger the opinions . David Lewis references “flawed computer models” are not even close to reality so the climate science response is change reality . A new growth industry …
    Reality Change Specialist . Send CV’s to NOAA .

    Why do these people like to refer to themselves as scientists ? How are they different from people that run program simulations on election results . They aren’t called scientists .

    Scientists follow the principles of scientific method which does not include changing data to support a hypothesis .

    Reply

  • Avatar

    David Barkin

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    First, there was no Global Warming, now, “Ok, there’s warming, it’s the Sun Stupid.”

    And what a shame that this year was NOT only the warmest on record, but warmest by over 1.4 of a degree.

    God could come down and tell you, we’re causing Global Warming, and you’d call It a Progressive Lunatic.

    [quote name=”David Lewis”]A quote from the article, “The study, which relied primarily on computer simulations.”

    So this study is using flawed computer models to support an agenda based on the flawed IPCC computer climate models. This is typical of the alarmist. They use simulations over real world data because things like the pesky satellite data don’t support their political agenda.[/quote]

    Reply

  • Avatar

    JayPee

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    @ Barkin’

    And the name of the G-d that talks to you ?

    Reply

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    amirlach

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    [quote]And what a shame that this year was NOT only the warmest on record, but warmest by over 1.4 of a degree. [/quote] Hey David Barkin! That’s complete and utter nonsense!
    [quote]2015 was not the hottest year on record and that satellite data shows temperatures were lower than previously thought. In fact, both 1998 and 2010 were warmer than 2015, and 2015 had an average global temperature of .27 degrees Celsius above the global average. This amount is so small as to be statistically insignificant.[/quote]

    The Satellite deniers are out in full force.
    [img]https://wattsupwiththat.files.wordpress.com/2016/01/satellite-deniers.jpg[/img]
    [quote]The recent act of desperation from the collection of Climategate Climateers trying to diss the satellite based global temperature record has spawned a cartoon, and it isn’t from our usual cartooning friend, Josh.[/quote]
    http://wattsupwiththat.com/2016/01/15/the-climateers-new-pause-excuse-born-of-desperation-the-satellites-are-lying/

    These satellite deniers have “adjusted” the surface temperatures so much that nearly the entire claimed temperature rise comes from said “adjustments”. Not from the actual recorded data.
    [img]http://www.ncdc.noaa.gov/img/climate/research/ushcn/ts.ushcn_anom25_diffs_urb-raw_pg.gif[/img]

    The Raw Data in no way supports the invalidated CAGW hypothesis.

    Reply

  • Avatar

    S Frankes

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    The Mann’s a goose pure and simple!

    Reply

  • Avatar

    amirlach

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    [img]http://bishophill.squarespace.com/blog/2016/1/30/new-era-josh-360.html[/img]

    “Thanks to Robert B over at WUWT who thought up a great name for the era of climate science we are currently enduring – The Adjustocene, where no one will ever know what the temperature is.

    Cartoons by Josh”

    http://bishophill.squarespace.com/blog/2016/1/30/new-era-josh-360.html

    Reply

  • Avatar

    JayPee

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    How astounding that the eternal schnabelist Herr Mann would gush forward with a worthless synopsia.

    He could lend some credit to his name if he published a thanatopsia.

    Are the ” publish or perish ” days coming back ?

    Why publish excremental verbiage ?

    Unless, of course, you don’t know it is.

    Reply

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