Laughable new paper claims 99.999% certainty global warming over past 25 years is man-made

Anthony Watts:

I was tipped off to this paper by a Tweet from SkS Reichfurher John Cook, and I started on writing a rebuttal, but discovered The Hockey Schtick had already done a complete job, so I’ve reposted it here.  -Anthony

The Hockey Schtick writes: A new paper published in a journal called “Climate Risk Management” claims a ridiculous degree of “certainty” of  99.999% that global warming over the past 25 years is man-made. The claim is made based upon climate models already falsified at confidence levels of 98%+.

According to the authors,

“there is less than a one in one hundred thousand chance of observing an unbroken sequence of 304 months [25.3 years] (our analysis extends to June 2010) with mean surface temperature exceeding the 20th century average.”

Fundamental problems with this claim [which is basically the falsified IPCC attribution claim of 95% certainty on steroids] include:

There is no statistical difference between the rate of warming over the 27 years from 1917-1944 and the 25 years from 1975/1976 to 2000:

Climate models fail to simulate the [natural with 99.999% certainty] observed warming between 1910 and 1940

Not being able to address the attribution of change in the early 20th century to my mind precludes any highly confident attribution of change in the late 20th century.” – Judith Curry

The IPCC’s attribution statement [and likewise this new paper is not seem logically consistent with the uncertainty in climate sensitivity

• “climate models are not fit for the purpose of detection and attribution of climate change on decadal to multidecadal timescales.” -Judith Curry
• Statistically significant global warming of the surface stopped 19 years ago and in the troposphere [which climate models claim should warm faster than the surface] global warming stopped 16-26 years ago
• Over 40 excuses for the 18-19 year “pause” in surface warming indicate that natural climate variability is far greater than climate models simulate, and is capable of overwhelming any climate influence of CO2
• Much of the warming of the past 25 years may be artificial due to urban heat island effects and extensive up-justing of temperature records long after the fact
• The paper uses climate models falsified at confidence levels exceeding 98%, thus the assumptions and conclusions derived from models are invalid

• The models also did not predict the 18-19 year “pause” in global warming, thus are not valid to determine attribution to natural vs. anthropogenic causes

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