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Wolfie00
My dog is an elitist
Premium Member
join:2005-03-12

2 edits

Wolfie00 to Ian1

Premium Member

to Ian1

Re: [Weather] Arctic sea ice melts to record low

There is no exaggeration on my part of your stance on this. The fact that you acknowledge that we should be reducing our GHG emissions is not an exoneration when you continue to attack the underlying science and the scientists without basis, and merely state that it seems "intuitively a bad idea" (your words) to dump all that CO2 into the air. What is truly tiresome and silly is the relentless attacks on sound science, using minor controversies exaggerated out of all reason or entirely falsified to try to cast doubt on well established conclusions.

You may be sincere in believing the accusations you make, but it doesn't change the facts or make them any more valid. I really don't care where you get the information for the claims you make -- the point is that the only backing for them is from disreputable blogs like that of Steve McIntyre, and the claims are either extremely misleading or, in most cases, entirely wrong.

Just some of the examples mentioned recently, which I provide for the edification of anyone interested.

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- the claim that Mann inappropriately used decentred PCA which created an artificial "hockey stick" pattern, and the claim that "the statistical approaches within the climate science community have been ham-handed at best..."

The decentred PCA technique in this context is arguably controversial, but absolutely does not lead to any of the erroneous results claimed. This was established by multiple sources including the National Academy of Sciences 2006 review, the Wahl and Amman 2007 paper, and others. It was far less controversial than many other methodologies that have been applied in pursuit of solid science, and became a theme of denialists because of McIntyre's false accusations. Furthermore, while you (or more precisely, McIntyre's blog) cites I.T. Jolie as claiming that it's bad statistics, Jolie's own book describes non-centred PCA as "a fairly well-established technique in ecology" and that " ... if the data are such that the origin is an important point of reference, then this type of analysis can be relevant." But the real point is it makes no substantial difference to the shape of the reconstruction, as one would expect from a properly applied PCA.

Climate scientists also work regularly with statisticians, recognizing the value of interdisciplinary collaboration -- that's why collaborations like the NCAR (National Center for Atmospheric Research) Geophysical Statistics Project were started.

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- the claim that "the analysis with and without the Bristlecones pines was substantially different" and that it's "a series that even the dudes that published the data stated was a terrible temperature proxy, and should never be used as one."

No, it wasn't. First of all Mann himself did exactly that comparison, and Wahl and Amman replicated those results and published them in the 2007 paper that was peer-reviewed and published in a leading journal (Climatic Change) with their detailed methodologies. Furthermore, no one stated that it was a "terrible" proxy, only that the bristlecones had shown unusual growth since about the mid-19th century, and whether they are useful as proxies depends on the reason why. Salzer et al, in "Proceedings of the National Academy of Sciences, 2009", concludes that the growth was indeed a response to temperature, and that therefore "multimillennial bristlecone pine ring-width time series at the upper forest border are a potentially valuable resource for information regarding past variability in temperature."

In other words, they are valid proxies, and their exclusion makes little substantive difference to the reconstruction anyway. Indeed, what their inclusion does is improve data quality, specifically the RE (reduction of error) in the PC regression.

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- the claim that "hiding the decline" was some nefarious conspiracy to eliminate "inconvenient" data without reason

The divergence of some high-latitude tree ring proxies from the temperature record in the second half of the 20th century was already discussed above. It's been known for more than 20 years and indeed one of the early papers on the subject was authored by Keith Briffa at CRU. The IPCC discusses it at length. The entire subject is a trumped-up pretext by denialists who either don't understand the concept or see it as a malicious opportunity to try to discredit good science.

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- this preposterous claim, quoted verbatim from you, which is a good way to wrap this up: "Nature likely didn't publish M+M 2003 for the reason that had they done so they would have looked like complete assholes ... for publishing MBH98"

For the readers, M+M is the dynamic duo of comedy, McIntyre and McKitrick, the former an economist and the latter a retired minerals prospector, both of whom are lobbyists against GHG regulation, and both of whom have been attacking climate science (and Mann in particular) for about the past decade. MBH98 is Mann's original long-term climate reconstruction paper.

The interesting thing is that M+M have a hard time getting anything at all published these days, have never and still do not do any actual climate research nor are they trained for it, and McIntyre spends most of his time running a disreputable blog. While meanwhile MBH98 is considered a landmark paper in climate science and has been verified and replicated by many other investigators and is now considered a foundational contribution to climate reconstructions. Mann himself runs a prestigious paleoclimate research group and has garnered numerous personal awards, as well as his share of the Nobel Prize awarded the IPCC. The claim that Mann was trying to "hide" the magnitude of the Medieval Warm Period is absurd since no reputable reconstruction shows a significantly elevated MWP temperature nor provides any evidence that it was more than a regional phenomenon mostly distributed around some parts of the Northern Hemisphere. Nor would it make any difference, since the (internal) causes and the spatial and temporal distribution of the MWP are reasonably well established. There are still a few denialists sufficiently disconnected from the science that they are still trying to push the implicit notion that whatever caused the MWP is now causing present warming. Nothing could be more ridiculous.

Ian1
Premium Member
join:2002-06-18
ON

Ian1

Premium Member

Yeah.... Wolfie00 See Profile. Good luck luck with your unique escapist hobby. You are suited to it. It's certainly more actually harmless than most.