It has been a couple of weeks since I posted a QOTW. This is mainly due to me being somewhat disengaged from the normal blogging pace due to some travel I’ve been doing and working on my upcoming papers. – Anthony
“If Michael Mann did not exist, the skeptics would have to invent him.”
This is from Roger Pielke Jr’s post on Mann’s new paper on hurricane frequency over the last 1000 years determined by proxy study of “overwash” of sand/silt deposits.
Pielke Jr. says (and have a look at the graph afterward):
I still find this hard to believe, is it possible that Mann has mislabeled his data files such that the smoothed data appears in the annual predictions column in his data file, rather than the raw counts? I find it hard believe that it is otherwise the case.
I was curious how the curve shown in Mann et al. discussed earlier today would look using adjusted data, and thanks to Michael Mann the data is up online allowing a comparison with data adjusted according to work in 2007 by Landsea (i.e., it doesn’t include the analysis from Landsea et al. released this week).
I graphed (above) the adjusted data (red curve) along with Mann et al.’s “predicted” historical data (blue curve, based on the Landsea data) both unsmoothed, just to see what it looks like — using information from these files at Mann’s directory:
Statistical Model Predictions of TC Past Activity
Alternative Case (uses Landsea ‘07 adjustment of historical TC
series) (AD 500-1850)
http://holocene.meteo.psu.edu/~mann/Nature09/TCStatModelReconLandsea.dat
Historical Tropical Cyclone (TC) counts
Alternative case [Landsea ’07 adjustments](1870-2006)
I now see why Mann claims that the Landsea adjustment does not matter. And he is right, it does not matter.
The Mann et al. historical predictions range from a minimum of 9 to a maximum of 14 storms in any given year (rounding to nearest integer), with an average of 11.6 storms and a standard deviation of 1.0 storms (!). The Landsea observational record has a minimum of 4 storms and a maximum of 28 with and average of 11. 7 and a standard deviation of 3.75. I suspected that a random number generator for hurricane counts since 1870 would result in the same bottom-line results and when I appended a series of random numbers constrained between 9 and 14 from 1870-2006 to the “predicted” values, lo and behold — 20th century values exceed every other point except about 1,000 years ago.
Mann et al.’s bottom-line results say nothing about climate or hurricanes, but what happens when you connect two time series with dramatically different statistical properties. If Michael Mann did not exist, the skeptics would have to invent him.
(1) Mann admits that he “is not a statistician,” and yet he keeps trying to play one. *sigh*
(2) What is it with Mann having extreme trouble when it comes to the accuracy of data files (if, as Pielke wonders, it is “possible that Mann has mislabeled his data files such that the smoothed data appears in the annual predictions column in his data file, rather than the raw counts”) in the rare instances where he actually does archive them?
If Michael Mann didn’t get so much coverage he would have to kidnap a bunch of actor looking journalists and lock them up in a very hot steam room until someone took notice of him.
But that’s another reality.
I am under the impression that the current generation of climatologists were programming games on their C-64 when they were kids, and have not changed a bit since.
[snip ad hominem to Dr. Mann, and of no value to this discussion]
So in Mann’s world, every year in the past was very much alike and everything was good. No ups, no downs.
It sounds a lot like the plot of the movie “Pleasantville” where every day is the same and nothing bad ever happens.
Is this about Michael Mann the climate scientist or Michael Mann the director? 😉
That is just hilarious.
Mann is a typical example of scientist who has sold out his scientific integrity to serve a political cause.
Mann might wish to be on the same level as Michael Moore.
If wishes were dishes, they’d all be broken, like GCM’s breaking all climate records.
Have any of these Climate Scientologists done evn a single introductory course in Statistics? Or even a course in “use your bloody head”? Again and again they produce stuff that would not be acceptable in a final year undergraduate research project.
“Alexej Buergin (11:30:22) :
I am under the impression that the current generation of climatologists were programming games on their C-64 when they were kids, and have not changed a bit since.”
C64 games were good, so things have changed.
That’s a hairy blade on that Hockey Stick! Are they sure it’s Mann’s and not Gavin’s? He’s much less clean shaven. 😉
RunFromMadness (12:58:53) :
“Alexej Buergin (11:30:22) :
I am under the impression that the current generation of climatologists were programming games on their C-64 when they were kids, and have not changed a bit since.”
C64 games were good, so things have changed.
You mean Atari? 🙂
Seriously, Mann is using a proper proxy; his work is what throws some doubts. Overwash sand and silt layers are suitable proxies for knowing the frequency of hurricanes striking the coastline in the past. Nevertheless, the researcher must be extremely attentive on sampling by boreholing:
We could not obtain a good record from boreholes taken only on four locations.
Oblique borehole samples are defective because we could be missing one or more overwash silt or sand layers or taking one layer as two different layers. The sampling must be entirely vertical.
We must to take at least 100 samples from a single location and from sectors that must be separated by 100 m^2 parcels, when it is possible. If not, the samples must be taken from areas separated at least by 10 m^2 parcels. Otherwise, the samples would be absolutely misguiding.
We have to eliminate samples obtained from locations where intensive human activity is registered. As all living beings, humans change habitats, though by far to a higher extent.
For example, I found 25% of topical magnetite in sand samples from the Pacific Ocean, which is an indication of the recent formation of the uppermost layer and that it is sand dragged by glaciers.
I am still in utter disbelief that Mann’s paper was published with exactly zero SST data on file at the time.
Unpossible….
I think we’re getting a bit too ad hominem, moderator, e.g. pinkisbrain (11:44:41) .
I forgot to say two things:
1. The hurricanes must have been enough powerful as to produce a high surge which could drag sand and accumulate it landwards upper from the shoreline.
2. Sometimes hurricane surges destabilize dunes above the shoreline; thus the effect could be the opposite of the expected.
From the viewpoint of competence, statistically, how probable is this “model”? Well outside 95% CI?
Ron de Haan (12:26:29) :
Mann is a typical example of scientist who has sold out his scientific integrity to serve a political cause
I wouldn’t go that far. I suspect he started off genuinely believing his work and has so much personal reputation and ego attached to it that he has now sold out. not for a political cause, but to his own ego!
I think nobody noticed it, but I made a mistake when I typeset this paragraph:
“For example, I found 25% of topical magnetite in sand samples.”
Heh! It should have been:
“For example, I found 2.5% of topical magnetite in sand samples.”
Sorry…
if you google michael mann, the first result is:
HEAT
a hollywood movie, thats funny, isnt it?
While I am all for questioning a lot of the assumptions and methodology in climate science and having a laugh at some of the circular logic, piling on the ad homs and speculating on the motives of certain climate scientists does tend to make us skeptics look a little petty, and I worry sometimes that it is indicative of the development of the dangerous groupthink mindset that blinds the pro camp.
Invention is the domain of the alarmist :
Real denial of Manmade Global Warming exists in the science, so alarmists have to invent doubt about the scientists of the denial. This is what William Connolley, and Kim Dabelstein Petersen have been doing for years, literally for years, in Wikipedia.
references :
http://network.nationalpost.com/np/blogs/fpcomment/archive/2008/05/03/who-is-william-connolley-solomon.aspx
&
http://network.nationalpost.com/np/blogs/fpcomment/archive/2008/04/12/wikipedia-s-zealots-solomon.aspx
——————————————
If you just enter “global warming” in google the first result you get points to the Wikipedia entry Connolley controls – and if you just wanted a two minute briefing on the subject you’d never know that the article is utterly and relentlessly dishonest.
http://blogs.zdnet.com/Murphy/?p=1190
It may sound bad science but if there is a consensus then it is the good science, the correct way of doing things and the conclusion is right. As climate science is evolving with all the consensus supporting the conclusion, then the data does not matter ( the reason they are brave enough to post it), the analytical procedure to handle the data does not matter, the methodology for gathering the data does not matter ( Anthony’s work on the location of the weather station is consdiered unimportant). In climate science it is right to splice data from whatevr source as long as it it further supports the consensus-(Mann is not alone). Climate science is just at the forefront of post normal science. The scientific method of the future. 1+1=3 because there is a consensus.
To be fair on all those scientists who we think have “sold their integrity” to the highest bidder, I think a lot of them know better than what they are cajoled into but understand they have to do what they are told and produce the desirable results. Otherwise, no funding, and dismissal
Michael Mann is the reason why a lot of us became GW skeptics in the first place. He certainly is the poster-child for bad statistical analysis.