8a. Climate Change - Phil Jones and the 'no warming for 15 years'

The perfect example of what I was saying in my last video appeared soon after it was uploaded. The Internet was abuzz with a quote from Professor Phil Jones that there has been no global warming since 1995.
But is that what he actually said? Once again, we need to go to the source -- Jones's own words -- rather than Internet gossip based on an interpretation of what he said. If we check the primary source, it's a very different story. In fact, Jones and his team did detect warming since 1995. In this video I go to the source, and find out why the tabloid press got things so wrong. I have to correct part of the video where I gave an example of what an 80% statistical significance would mean (for the statisticians out there, this is a p-value of 20%). I said this would mean 80% confidence that global warming was a real, underlying trend, and not the result of background fluctuations.
While some statisticians accepted this as a broad explanation for the layperson, others felt it deviated too far from the precise meaning, which is this: =If global warming was not happening, there is only a 20% chance we would see this result.= A 90% statistical significance (if that's what Jones achieved) of the 1995-2009 temperature data would mean If global warming was not happening, there is only a 10% chance we would see this result.




Link to Daily Mail story:
http://www.dailymail.co.uk/news/article-1250872/Climategate-U-turn-Astonishme...

Link to transcript of BBC interview:
http://news.bbc.co.uk/2/hi/8511670.stm

Category:

Education

Tags:

• statistically
• significant
• global
• warming
• phil
• Jones
• Daily
• Mail
• climate
• chnage
• potholer54
• debunks

[CHIPSTERO7]

Also, rock-strata paleoclimate data going back 600-million years (unlike ice-core) shows no correlation and ice-core shows an 800-year lag. I thought I should add that in to quantify my previous statement: "if the paleoclimate data suggests CO2 effects temperatures".

[potholer54]

@CHIPSTERO7 =rock-strata paleoclimate data going back 600-million years (unlike ice-core) shows no correlation= Really? What is your source for this?

[CHIPSTERO7]

@potholer54 My sources are Scotese and Berner. See here for more info: ht tp://ww w.geocraft.com/WVFossils/Carbo­niferous_climate.ht ml (remove the spaces in the link).

[potholer54]

@CHIPSTERO7 -- Thanks, but the link you gave me is an Internet blog. I hope you understand that anyone can publish a blog saying whatever they like, so this is not a reliable source. As for Scotese and Berner (paleomap project) please cite a paper, or a statement, or whatever you read of theirs that told you CO2 and temps do not correlate over the phanerozoic. I could find nothing.

[TheShowThatSUX]

You make a good point about statistics here, and it is actually right at the root of why novices on both sides make false assumptions about what data shows. Lets say we enter or have entered a period of cooling...it wont be immediately clear. We have a historic period of warming which means it can take 10-50 years for a prided of cooling to statistically be properly weighted. And that is the real problem on both sites the proper science has a rather long lag to even read the data correctly.

[ndrthrdr1]

This video deserves more views - and Likes.

[listen2meokidoki]

@listen2meokidoki Or!....Or the so called comment (hotter then than now) was written by a journalist/Editor simply because it was not attributed and most climate skeptics are inherently ignorant and therefore inarticulate compared to me, whom is of a superior education. And I can assure you, the parrot is simply resting.

[listen2meokidoki]

Dear Potholer54. Your comments have a 95% confidence level in truthfulness. But can we (predominantly you lol) prove with accuracy that the climate skeptical movement is DELIBERATELY promoted by journalist & editors? accusing them of having only a NUGGET of knowledge lets themoff IMHO. They must deliberately hide behind that assumption (that you seem to reinforce) to promote shit because it stirs up the readership which does understand bullshit more easily than a peer review; whatever that is.

[listen2meokidoki]

That quote in the Daily Mail by skeptics: .."could have been hotter then than now". Proves that the skeptic who penned that comment must be older than 30 with a confidence level greaterthan 95% because all eople younger than 30 can not distinguish between THEN and THAN. Therefore they could never construct such a sentence. At best they might say .."hotter than then now". This is because young people are ignorant beyond their years. Especially in the USA where it is taught as dogma..

[followthefleet1]

Excellent post focusing on the exact words of Professor Jones, who never denied climate change at all. Today according the US Academy of Science, scientist Dr. Richard Alley, "almost no one"...referring to climate scientists...denies anthropogenic climate change. Note that vested carbon interests today will distort any statement to their purposes. An excellent post by potholer 54.

[vinvanveen]

This is all academic now, since the trend now *is* statistically significant -- however, does anyone know whether Jones used a one-sided or two-sided test?

I'm not a climatologist, I'm in neuroscience. In that field (as well as other sciences like psychology), when a prediction is straighforward (e.g., obtained from a computational model), a one-sided test is more than appropriate. So, if Jones' obtained P was 7.5%, this is significant when using a one-tailed alpha=5% criterion.

[dartplayer170]

BTW, the actual significance level from the period 1995 to 2009 achieved by Phil Jones' linear regression t-test was 92.5% but this is all just a smoke screen anyway. The real question that should be asked is whether there is any significance to using linear regression to analyze temperature data!

[meghaljani]

@potholer54 There is a link to a scientific paper on the page. I downloaded the pdf.