date: Fri Oct 22 15:13:20 2004
from: Phil Jones <p.jonesatXYZxyz.ac.uk>
subject: Re: MBH
to: Tom Wigley <wigleyatXYZxyz.ucar.edu>
Just got the Science attachments for the von Storch et al. paper for Tim and Keith, so
I thought you might like to see them. I've just sent a reply to von Storch as he claims
his model is a better representation of reality than MBH. How a model that is only given
past forcing histories can be better than some proxy data is beyond me, but Hans seems
to believe this. The ERA-40 report and JGR paper are relevant here. ERA-40 is not of
climate quality. There are differences and trends with CRU data before the late 1970s
and again around the mid-1960s that should include other variables that are calculated.
It is so bad in the Antarctic that ERA-40 rejects most of the surface obs (because they
get little weight) and they don't begin to get accepted until the late 1970s. Conclusion
you can't consider ERA-40 for climate purposes. Maybe the next generation, with a
efforts in getting all the missing back data in and changes to weights given to surface
mean the 3rd generation is better.
I shouldn't rabbit on about this as I have to go home to drive with Ruth to Gatwick
our week in Florence. A lot of people criticise MBH and other papers Mike has been
involved in, but how many people read them fully - or just read bits like the attached.
The attached is a complete distortion of the facts. M&M are completely wrong in virtually
everything they say or do. I have sent them countless data series that were used in the
Jones/Mann Reviews of Geophysics papers. I got scant thanks from them for doing this -
only an email saying I had some of the data series wrong, associated with the wrong
I wasted a few hours checking what I'd done and got no thanks for pointing their mistake
If you think M&M are correct and believable then go to this web site
It will take a while to get around these web pages and you've got to be a bit of nerd and
the jargon, but it lists all the mistakes McKittrick has made in various papers. I bet
a link to this on his web site. The final attachment is a comment on a truly awful paper
McKittirck and Michaels. I can't find the original, but it's reference is in this. The
consider spatial autocorrelation at all. Fortunately a longer version of the paper did get
rejected by IJC - it seems a few papers are rejected !
Point I'm trying to make is you cannot trust anything that M&M write. MBH is as good a
way of putting all the data together as others. We get similar results in the work in the
Holocene in 1998 (Jones et al) and so does Tom Crowley in a paper in 1999. Keith's
reconstruction is strikingly similar in his paper from JGR in 2001. Mike's may have
slightly less variability on decadal scales than the others (especially cf Esper et al),
he is using a lot more data than the others. I reckon they are all biased a little to the
and none are truly annual - I say all this in the Reviews of Geophysics paper !
Bottom line - their is no way the MWP (whenever it was) was as warm globally as the
last 20 years. There is also no way a whole decade in the LIA period was more than 1 deg C
on a global basis cooler than the 1961-90 mean. This is all gut feeling, no science, but
years of experience of dealing with global scales and varaibility.
Must got to Florence now. Back in Nov 1.
At 20:46 21/10/2004, you wrote:
I have just read the M&M stuff critcizing MBH. A lot of it seems valid to me.
At the very least MBH is a very sloppy piece of work -- an opinion I have held
for some time.
Presumably what you have done with Keith is better? -- or is it?
I get asked about this a lot. Can you give me a brief heads up? Mike is too
deep into this to be helpful.
Prof. Phil Jones
Climatic Research Unit Telephone +44 (0) 1603 592090
School of Environmental Sciences Fax +44 (0) 1603 507784
University of East Anglia
Norwich Email p.jonesatXYZxyz.ac.uk