2011-09-02 02:24:56Roy Spencer-- can you spot the big lie?
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

This is the latest diatribe from Spencer. Read it and weep.  Can you spot the big lie? "Obscurity" (moi) takes Roy to task.

"The above opinion piece by Roy is a perfect  example as to why he is rapidly losing credibility in the global scientific community. Worse yet, his decision to include a outdated and misleading graphic is not helping his case (see below).

 

It seems that if all else fails then Roy resorts to conspiracy theories and ad hominem attacks on Al Gore-- that is not science, and neither is citing the much flawed Loehle (2007).  And that brings me to one of the more egregious errors in Roy's above opinion piece. <b>Why does Roy show Loehle (2007) and not Loehle and McCulloch (2008), which included corrections to errors made in Loehle (2007)?</b> That is being incredibly disingenuous and misleading Roy. Here is a more complete picture or the proxy data:

http://www.skepticalscience.com/new-remperature-reconstruction-vindicates.html


In fact, there is something very wrong with Roy's graph, as N. Hemisphere temperatures are now known to be running warmer than those most likely observed during the Medieval warm anomaly.
 

<b>Regardless showing an outdated and flawed paleo graphic is just an old trick to distract people from where we are heading as Roy urges to continue with BAU</b>.  And let me note the logical fallacy by Roy here-- according to Roy paleo data are a "grey" are of research, except of course when a cherry-picked (and flawed) paper claims to show that N. Hemisphere temperatures are as warm as they were during the Medieval climate anomaly.  And another logical fallacy by Roy, funny how Roy chooses to use temperature data (global or N. Hemisphere Roy please be specific?) compiled by those alleged "corrupt" scientists from CRU that he and his readers despise so much probably full knowing that the HadCRUT has a been demonstrated to have a cool bias (can't provide a link b/c of the spam filter, but the UK Met office has shown this).

Really Roy, you really ought to know better and to up your game. This latest gaff by you is, IMO, running dangerously close to committing scientific misconduct."

2011-09-02 02:46:44
dana1981
Dana Nuccitelli
dana1981@yahoo...
69.230.106.125

Here's the post in question.  And the graphic in question:

Spencer Loehle

Worse than Spencer's use of Loehle (2007) is his equating science and statistics with religion:

"When the IPCC talks about the high “probability” that warming in the last 50 years is mostly manmade, they are talking about their level of faith."

And of course it's full of the usual Spencer conspiracy theories, as Alby notes.  I see that he's still been writing ignorant blog posts about economics, too.

2011-09-02 02:49:15Out of curiousity...
John Hartz
John Hartz
john.hartz@hotmail...
98.122.98.161

Has Spencer posted any comments about SkS articles that have taken him to task?

2011-09-02 02:58:11
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

Thanks Dana!

2011-09-02 03:11:06
Ari Jokimäki

arijmaki@yahoo...
91.154.106.251

With just a quick peek, here's one of his smaller lies:

"Besides, as a meteorologist I must question the whole idea of 100-year event. Since even the longest weather station datasets only go back about 100 years, it is questionable whether we can even say what constitutes a 100-year event."

Hmm... longest weather station datasets extend at least back to 1700's, I think. Surely back to 1800's.

2011-09-02 03:41:07
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

Ari,

I'm no statistician, but it is my hunderstanding that one does not necessarily need 100 years or more of data to determine the likelihood of a 100-year event.  Dikran or KR would be the persons best equipped to address this.

Maybe someone shouold ask Tamino...?

2011-09-02 03:59:22
Dikran Marsupial
Gavin Cawley
gcc@cmp.uea.ac...
139.222.14.107

No, you don't need necessarily 100 years worth of data, the branch of statistics you need is called "extreme value theory", but there are even more basic ways you can make a sensible estimate.  If you assume that the statistic of interest is Gaussian and you have (say) 20 samples from which to estimate a mean and variance, then there is no reason that you shouldn't use that statistical model to estimate the maximum value you would expect to see from 100 samples, or 1000 or 1000000.  As the extreme becomes more extreme, the more sensitive it is likely to be to the uncertainty in estimating the parameters, but you can always take a Bayesian approach and integrate out that source of uncertainty.

Nuclear reactors are designed to resist one in a (large number) year events (such as earthquakes or tsinami etc.), but they didn't have (large number) years worth of data to use.

As a meteorologist, perhap he should have asked a statistician (Tamino would be a good choice as it is time series data)

2011-09-02 04:02:58
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

Thanks Dikran!

You are probably not interested (and I don't blame you), but it might be worth (for what it is worth) pointing this out to Roy. It is quite the glaring misunderstanding/error on his part...embarrassing for him really, but even more so when it is highlighted by someone.

2011-09-02 04:12:28
Dikran Marsupial
Gavin Cawley
gcc@cmp.uea.ac...
139.222.14.107

I'm afraid my comments on Roys blog no longer seem to make it through moderation.  However you could always point him towards the excellent introduction by Stewart Coles

http://www.amazon.co.uk/Introduction-Statistical-Modeling-Springer-Statistics/dp/1849968748

2011-09-02 04:31:26
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

Hi Dikran,

That is odd-- re your posts not apearing.  I know hw has a very aggressive "spam" filter, so one can only post one URL.  But perhaps he does not like being challanged by someone in the know.

Would it be OK for me to paraphrase what you said at 3:59 am and post the link that you provided?

2011-09-02 04:45:02
Dikran Marsupial
Gavin Cawley
gcc@cmp.uea.ac...
139.222.14.107

yes, go ahead, though I should add the caveat that I am not expert on time-series statistics - Tamino would be a better advisor.  However, perhaps you should ask Roy to comment on the plot on page 139 of Coles' book that gives the distribution of 100-year return level for minimum temperatures calculated from a five year temperature time series (Wooster, Ohio - presumably like myself Coles is a fan of P.G. Wodehouse ;o), however I haven't enough time to read the chapter properly today. ;o)

The thing Roy doesn't understand is that there is never too little data to be able to make some statistical inference, the only thing that changes is the certainty with which you make the inference.  If you have zero data there is infinite uncertainty, if you have an infinite amount of data there is zero uncertainty, most of the time we are somewhere in the middle and you need to look at the credible interval (error bars) on the prediction to know whether it is plausibly worthwhile/useful.

2011-09-02 05:01:54
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

Thanks again Dikran, much appreciated!  Maybe I'll ask Grant Foster, just to make sure.

2011-09-02 06:03:24
dana1981
Dana Nuccitelli
dana1981@yahoo...
69.230.106.125

badger - to my knowledge, Spencer has never said a word about our SkS posts.

2011-09-02 08:56:26
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

OK, i've emailed Tamino.  Will let you know what he says if he has time to respond-- i'm sure he gets many requests each and every day.

2011-09-02 09:43:06Comment
Robert Way

robert_way19@hotmail...
142.162.9.162

Haha it's funny to see this here but I saw the post on spencer's blog and was wondering about the same thing but thought i'd leave it be