Sentences with phrase «hockey stick shaped»

The reason is that the temperature trend itself is hockey stick shaped.

Hockey stick shaped reconstructions «proved» something odd was happening in recent times, variable reconstructions indicated a high sensitivity — either way was «not inconsistent with» the narrative.

McIntyre and McKitrick claimed that the «short - centred» method, when applied to so - called «persistent red noise», nearly always produces a hockey stick shaped first principal component (PC1).

Yes, they are now lost with a hockey stick shaped hole in their hearts and minds, and they can't find anything to fill it.

Basically the climatologists who have produced hockey stick shaped graphs have done so by carefully selecting proxies that produce the results they want.

I consider the 20th century temperature record to be reliable, roughly hockey stick shaped over the last 1000 years and there has been no significant data manipulation.

C: increase in atmospheric CO2 from pre-industrial to present is anthropogenic (D / A) S: best guess for likely climate sensitivity (NUM) s: 2 - sigma range of S (NUM) a: ocean acidification will be a problem (D / A) L: expected sea level rise by 2100 in cm (all contributions)(NUM) B: climate change will be beneficial (D / A) R: CO2 emissions need to be reduced drastically by 2050 (D / A) T: technical advances will take care of any problems (D / A) r: the 20th century global temperature record is reliable (D / A) H: over the last 1000 years global temperature was hockey stick shaped (D / A) D: data has been intentionally distorted by scientist to support the idea of anthropogenic climate change (D / A) g: the CRU - mails are important for the science (D / A) G: the CRU - mails are important otherwise (D / A)

If they were unbiased they would bracketed the real answer but they are all skewed to the high side, with the added benefit that they are hockey stick shaped.

After all, surely the addition of this little hockey stick shaped data curve to the raw data is not arbitrary simply to get the answer they want, the additions have to represent the results of some heretofore unaccounted - for bias in the raw data.

(b) With respect to Mann et al. [1998, 1999](MBH98 - 99), our most important objections [see McIntyre and McKitrick, 2003, 2005a, 2005b, 2005c, 2005d and www.climateaudit.org] are: • The study used «new» statistical methods that turned out to «mine» for hockey stick shaped series.

If (1) you have a few hockey stick shaped series in a smallish data set which otherwise is cancelling noise, and (2) then re-scale your average to a temperature scale in the calibration period, you can get hockey stick shaped «reconstructions».

The VZ procedure simply does not generate hockey stick shaped PC1s and can not be used to test the impact of the MBH98 methodology.

The VZ procedure simply does not generate hockey stick shaped PC1s in the way that the MBH98 procedure does and can not be used to test the impact of the MBH98 methodology.

My still unanswered question is why does the hockey stick shape of Earth temperatures show up in a chart of the Solar magnetic flux?

My still unanswered question is why does the hockey stick shape of Earth temperatures show up in a chart of the Solar magnetic flux?

So you are unaware that removing one proxy from their study (Bristlecone pines) completely eliminates the hockey stick shape?

«[Skeptics are] blind to the fact that the hockey stick shape of climate over the past 1000 - 2000 years isn't dependent on tree rings, Mike Mann or Ray Bradley.»

They concluded that the hockey stick shape was not statistically significant.

To my knowledge, the proxies you mention are for the most part (1) scarce, (2) incompletely validated, and / or (3) lacking in adequate (decadal or better) resolution for «hockey stick shape» determination.

You also claim that McI and McK were correct when they showed that Mann's statistical method produces hockey stick shapes from trendless red noise but then you write «they would have a valid point in principle, but the critique would not matter in the case of the hockey - stick.»

At 7:56 am, you were discussing «the hockey stick shape of climate over the past 1000 - 2000 years.»

Here are a number of new studies that do not have a hockey stick shape.

The BCPs impart the hockey stick shape, the rest of the proxies are basically just white noise.

Wahl and Ammann reject this criticism of MM based on the fact that if one adds enough principal components back into the proxy, one obtains the hockey stick shape again.

He illustrated this using the «principal components analysis,» in which the hockey stick shape emerges as one includes higher components, which are necessary for proper application of this technique.»

«A further aspect of this critique is that the single - bladed hockey stick shape in proxy PC summaries for North America is carried disproportionately by a relative small subset (15) of proxy records derived from bristlecone / foxtail pines in the western United States, which the authors [MM] mention as being subject to question in the literature as local / regional temperature proxies after approximately 1850.

If Mann had used the correct data, there would have been no hockey stick shape.

If tree - ring temperature reconstructions have the effect of ironing out peaks and valleys — and you seem to agree they do — then appending an instrument record that happens to correspond to a peak, will always yield a hockey stick shape.

I do not think there is any convincing evidence to support a hockey stick shape for global temperature anomalies of the past 1000 - 2000 years, with any kind of confidence.

Without the bristlecone pines the overall MBH98 results would not have a hockey stick shape, instead it would have a pronounced peak in the 15th century.

Put simply, McIntyre showed a series with a prominent hockey stick lost it's hockey stick shape if a little data from the same area was added.

He did this very experiment himself and discovered that the PCs lose their hockey stick shape when the Graybill - Idso series are removed.

Also, like you say, in his inexorable quest to remove any hockey stick shape whatsoever from the historical paleoclimate record, McIntyre insisted on using only PC1 — even though MBH98's short - centred PCA methodology required that all significant principle components were captured.

Although the «samples» that wegman's report show seem to be derived from the 100 most positive values of HSI, based on M&M's code that DC showed in his excellent post, it seems from the histogram, that there is a indeed a strong tendency for a hockey stick shape to appear in PC1 with the non centered principal components procedure.

What the graph shows (in plain English) is how the purple data set was deleted from the equations (and graph) and replaced with the thick black data at the end of the series — which gave this chart and all its later version the Hockey Stick shape.

What is missing in all this is whether the higher order PC's that would have been derived from the red noise proxies, and included in the full PCA, would have eliminated the hockey stick shape in the full representation of the data, using the correct number of PC's.

As Muller reported in his Technology Review article, there were math errors made by Mann et al. that would have caused randomized data input to the program to have an output that had the hockey stick shape.

I've got eight other graphs on the DeSmog Blog, none of which has been questioned in the least, all showing a hockey stick shape in the temperature from 1,000 years ago to today, and all of them showing a pretty similar — the idea that there was a Medieval Warming Period during which the temperature was higher than it is now is, that is like, flagrantly incorrect is the nicest way that I can say it.

If either plot shows a hockey stick shape with an inflexion point in the late 19th century, he may be on to something.

Ice core data supports the general cooling trend in case of the last 2000 years, but the hockey stick shape is missing again: http://www.foresight.org/nanodot/wp-content/uploads/2009/12/histo4.png

They also dispute McIntyre and McKitrick's alleged identification of a fundamental flaw that would significantly bias the MBH climate reconstruction toward a hockey stick shape.

The resulting reconstruction showed a rise in temperature in the medieval period, thus eliminating the hockey stick shape.

I'll simply note that the McShane and Wyner millenial reconstruction has a pronounced hockey stick shape, albeit with a higher Medieval Warm Period and wider error bars than the norm seen in various spaghetti graphs (apparently attributable to the Bayesian «path» approach).

It was clear that the Yamal data differed from Hantemirov and Shiyatov because it produced totally wrong results because the Hantemirov and Shiyatov data had no hockey stick shape.

The big selling point of Mann's new paper was that you could get a hockey stick shape without tree rings.

However, when he did this test, the hockey stick shape of the final reconstruction came from the bristlecones.

Do you not accept that the last 1000 - 2000 years of T is likely to have a hockey stick shape?

The basis for selection, obviously, was not whether trees exhibited a hockey stick shape or not; in cases where there are enough instrumental data, the criterion is whether they correlate well to that — too bad the temperature data show warming over the 20th century, I suppose.

A hockey stick shape still remains, no matter what you do.

A hockey stick shape in a data set provides a perfect opportunity, since the blade of the stick represents a significant excursion from the shaft of the stick, while the shaft represents the stable system that we need to start with.