UPDATE: a response to this paper has been posted, see below.
From McGill University , who blows the credibility of their science by putting the word “deniers” in it.
Statistical analysis rules out natural-warming hypothesis with more than 99 percent certainty
An analysis of temperature data since 1500 all but rules out the possibility that global warming in the industrial era is just a natural fluctuation in the earth’s climate, according to a new study by McGill University physics professor Shaun Lovejoy.
The study, published online April 6 in the journal Climate Dynamics, represents a new approach to the question of whether global warming in the industrial era has been caused largely by man-made emissions from the burning of fossil fuels. Rather than using complex computer models to estimate the effects of greenhouse-gas emissions, Lovejoy examines historical data to assess the competing hypothesis: that warming over the past century is due to natural long-term variations in temperature.
“This study will be a blow to any remaining climate-change deniers,” Lovejoy says. “Their two most convincing arguments – that the warming is natural in origin, and that the computer models are wrong – are either directly contradicted by this analysis, or simply do not apply to it.”
Lovejoy’s study applies statistical methodology to determine the probability that global warming since 1880 is due to natural variability. His conclusion: the natural-warming hypothesis may be ruled out “with confidence levels great than 99%, and most likely greater than 99.9%.”
To assess the natural variability before much human interference, the new study uses “multi-proxy climate reconstructions” developed by scientists in recent years to estimate historical temperatures, as well as fluctuation-analysis techniques from nonlinear geophysics. The climate reconstructions take into account a variety of gauges found in nature, such as tree rings, ice cores, and lake sediments. And the fluctuation-analysis techniques make it possible to understand the temperature variations over wide ranges of time scales.
For the industrial era, Lovejoy’s analysis uses carbon-dioxide from the burning of fossil fuels as a proxy for all man-made climate influences – a simplification justified by the tight relationship between global economic activity and the emission of greenhouse gases and particulate pollution, he says. “This allows the new approach to implicitly include the cooling effects of particulate pollution that are still poorly quantified in computer models,” he adds.
While his new study makes no use of the huge computer models commonly used by scientists to estimate the magnitude of future climate change, Lovejoy’s findings effectively complement those of the International Panel on Climate Change (IPCC), he says. His study predicts, with 95% confidence, that a doubling of carbon-dioxide levels in the atmosphere would cause the climate to warm by between 2.5 and 4.2 degrees Celsius. That range is more precise than – but in line with — the IPCC’s prediction that temperatures would rise by 1.5 to 4.5 degrees Celsius if CO2 concentrations double.
“We’ve had a fluctuation in average temperature that’s just huge since 1880 – on the order of about 0.9 degrees Celsius,” Lovejoy says. “This study shows that the odds of that being caused by natural fluctuations are less than one in a hundred and are likely to be less than one in a thousand.
“While the statistical rejection of a hypothesis can’t generally be used to conclude the truth of any specific alternative, in many cases – including this one – the rejection of one greatly enhances the credibility of the other.”
“Scaling fluctuation analysis and statistical hypothesis testing of anthropogenic warming”, S. Lovejoy, Climate Change, published online April 6, 2014. http://link.springer.com/search?query=10.1007%2Fs00382-014-2128-2
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Christopher Monckton has posted a rebuttal to this paper, see here
I’m 99% certain that this stinks
Yeah, this is like the eugenicists “discovering scientifically” that their own racial characteristics just happened to be the ideal characteristics for humanity, and that they needed to help make certain the inferior races were eradicated, all for the science, of course.
Before you tell me with 95% certainty that the recent (modest) warming is due to man you must tell me how the vastly greater temperature swings both up and down happened. Crickets
Otter (ClimateOtter on Twitter) says:
April 11, 2014 at 4:17 pm
“Never heard of McGill university. Probably will never hear of it again.”
Oh dear, we better fix this. Don’t say this too loudly:
http://en.wikipedia.org/wiki/McGill_University
“McGill is one of two member-universities of the Association of American Universities situated outside the United States.[10]
McGill was ranked 1st in Canada among all its major/research universities in the Maclean’s 23rd annual rankings (2013-2014 school year), maintaining this position for the ninth consecutive year.[11] Internationally, McGill ranked 21st in the world and 2nd in Canada in the 2013 QS World University Rankings.[12] Bloomberg BusinessWeek’s 2012 Business Schools Ranking ranked McGill’s Desautels Faculty of Management 10th in the world among non-US business schools, referring to McGill University as “the #1 university in Canada and among the top 20 worldwide.”[13] McGill was ranked 33rd in the world and 2nd in Canada by the 2014 Times Higher Education World University Rankings.[14] In the 2011 Emerging/Trendence Global Employability Ranking, McGill was ranked the 19th finest in the world, and 1st in Canada, for popularity among major employers.
Oh and: Notable alumni include nine Nobel Laureates, 135 Rhodes Scholars (the most in the country),[7] three astronauts, two Canadian prime ministers, twelve justices of the Canadian Supreme Court,[8] four foreign leaders, twenty-eight foreign ambassadors, nine Academy Award winners, three Pulitzer Prize winners, and twenty-eight Olympic medalists. McGill alumni were instrumental in inventing or initially organizing football, basketball, and ice hockey.[9]”
But yeah, climate research/physics (these days), nothing to rave about even though Ernest Rutherford, Einstein’s pa taught their!!
Oops, Einstein’s pal, not “pa”
Like Batman seeing a modified Klieg searchlight …..
Soon will appear McIntyre.
Yay! This should be entertaining!
Current Global sea ice anomaly has today moved greater than 1 million Km2 above the 30- yr. avg.
Nature is offering a rebuttal, eh?
His study predicts, with 95% confidence, that a doubling of carbon-dioxide levels in the atmosphere would cause the climate to warm by between 2.5 and 4.2 degrees Celsius. That range is more precise than – but in line with — the IPCC’s prediction that temperatures would rise by 1.5 to 4.5 degrees Celsius if CO2 concentrations double.
Here’s the thing. If they come up with a sensitivity in line with the IPCC’s, “b>then they have the exact same problem that the IPCC has!
They’ve calculated a sensitivity that should have over whelmed natural variability as CO2 emissions accelerated. Instead, the opposite is true. They can’t argue that sensitivity absolutely dominates natural variability and then explain the last two decades of no warming due to natural variability dominating the sensitivity to the highest levels of CO2 ever.
These people will never play on an equal playing field . Its about demonizing your opponent.
SImple. You have the truth. Then you have lies, damn lies and after that comes statistics.
The study depends on equating paleo-temperature proxies to physical temperature. That means the crockology of statistical proxies pretending physical meaning applies to Lovejoy’s work as well.
Looking at the paper, the proxies in his Figure 5 are plotted at an accuracy of 0.1 C, implying 1-sigma = (+/-)0.05 C, for a paleo-temperature proxy that has no known physical relationship with temperature (except dO-18, which is never used in its physical sense in paleo-temperature reconstructions).
Figure 5 also plots the surface air temperature record without any error bars.
Figure 7 is plotted with an implicit claim of temperature accuracy of (+/-)0.02 C, and in the same figure Lovejoy claims to be able to detect a paleo-temperature natural variabilty of (+/-)0.2 C.
None of it is connected to physics. The entire study is a complicated exercise in false precision.
The first sentence of the Introduction is amusing, in an ironic sense: “Well before the advent of General Circulation Models (GCM’s), (Arrhenius 1896), proposed that greenhouse gases could cause global warming and he even made a surprisingly modern quantitative prediction. (my bold)”
The proper meaning of the sentence is that modern GCMs make surprisingly primitive predictions.
And look at this, the Lovejoy raison d’etre: “But there is yet another reason for seeking non-GCM approaches: the most convincing demonstration of anthropogenic warming has not yet been made—the statistical comparison of the observed warming during the industrial epoch against the null hypothesis for natural variability.
He says that a statistical comparison will provide “the most convincing demonstration of anthropogenic warming“!
Earth to Prof. Lovejoy: the only demonstration of physical causality is provided by a falsifiable physical theory. Causality is never, ever provided by statistics or statistical correlations. No wonder he’s so confident in his pronouncements: he’s got no understanding of the source of physical knowledge. Like everything else AGW, we have certainties expressed by people who don’t actually know what they’re talking about. But, hey! the math is complicated.
Smart comments.
First there was a 95% meme ….
Recently followed by a 97% meme ….
And now they’re spawning a 99% meme …
If the pattern continues we’ll soon see the hyperventilating hyperbole of sports stars …
They’ll soon be giving us a 101% meme!
Lovejoy’s study applies statistical methodology to determine the probability that global warming since 1880 is due to natural variability. His conclusion: the natural-warming hypothesis may be ruled out “with confidence levels great than 99%, and most likely greater than 99.9%.”
moron….
http://www.foresight.org/nanodot/wp-content/uploads/2009/12/histo3.png
What this comes down to is:
1. The models calculate a sensitivity that has been falsified by observations.
2. This is a statistical analysis that calculates a sensitivity that has been falsified by observations.
I could statistically analyze the incidence of toe fungus and be 99.9% certain that it has an impact on dog food consumption, with the same level of validity in this paper. No models needed either.
See: Magnus H, et al. (2013) The incidence of tinea pedis and correlation with canine caloric intake. J. Virt. Nonsense 1: p. 23.
I’ll hurry up and write that, then go back in time to publish it for you. Does anybody want to be a coauthor? Do we need to say it was caused by climate change?
“If your experiment needs statistics, you ought to have done a better experiment.”
Ernest Rutherford
(Baron Rutherford of Nelson. New Zealander born British Chemist who laid the groundwork for the development of nuclear physics by investigating radioactivity. Nobel Prize in 1908. 1871-1937)
Good old McGill. Going to heck in a hand-bag.
I keep telling you AGW is a religion, a cult. Some people are hard wired to be religious. And with religions like Christianity off the table as not hip, not cool, not acceptable in The Capitol (Hunger Games) they have to invent one or join one. I’m an atheist, and a conservative, I think all religions are at best questionable, this one especially so. I want a dull life. I do not want to live in “interesting times”. Do I fear change? No but I want useful, usable, change. Not change just to have change. Not this… this mental masturbation wrapped in angst and guilt seeking salvation in a make believe “saving the world” fantasy. Come on guys, grow up!!!
skience on April 11, 2014 at 5:04 pm
“This is just a rehash of failed science.”
…
———
Right!
In order to calculate an F statistic, one needs to know the mean sum of squares attributed to the noise. Having at best 100 years of instrument records (globally), I doubt the error term is robust, considering the planet is 4.5 billion (with a “B”) years old.
I don’t think a lot of scientists really appreciate “scale”. Given the planet is 4.5 billion years old, proportional to a long human life of 100 years, the past 100 years of instrument record would be akin to 12 minutes of human life.
Imagine a person using 12 minutes of his life to observe something and then claiming he understands everything about it and can project infinitely into the future.
“Shaun Lovejoy’s biggest blunder is his mistaken belief about what the “deniers” actually believe.
He claims they believe that only natural forces have caused the warming. He’s creating a straw
man here. I claim he won’t be able to name any serious “deniers” who actually believe that humans haven’t caused at least some of the warming. Exactly why is Lovejoy so dumb about this?”
Lol, there are a lot of people here who are very serious about denying that the planet is warming at all, or denying that humans are responsible for any warming if it is happening. Calling Lovejoy dumb about this, is having yourself on about what a lot of people here believe.
Ridicule is the only effect [weapon] against demonization that why this site is so effective.Keep hammer them or its the killing fields for you
Almost laughable……. basically, it would appear they are cherry picking hockey stick data and coming to the conclusion that only CO2 can explain it. Michael Mann’s hockey stick showed exactly the same thing, problem is… the Hockey Stick was shown to be fraudulent. They obviously aren’t applying this type of analysis to the Central England temperature records. They know that without validation of Hockey stick temperatures for the past 100 yrs their CAGW case falls completely flat.
[+emphasis]
I note the author left himself a little bit of wriggle room.
Perhaps McGill University physics professor Shaun Lovejoy would gain some insight into “certainty” if he conversed with physics professor at Duke R. G. Brown.
“This study will be a blow to any remaining climate-change deniers,”
This is the disgusting language of an activist, not a scientist. Not worth to read any further.