date: Tue, 07 Jun 2005 10:46:06 +0100
from: Tim Osborn <t.osborn@uea.ac.uk>
subject: Fwd: Re: IPCC AR4
to: "Keith Briffa" <k.briffa@uea.ac.uk>

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>Reply-To: "Rob Wilson" <rjwilson_dendro@blueyonder.co.uk>
>From: "Rob Wilson" <rjwilson_dendro@blueyonder.co.uk>
>To: "Tim Osborn" <t.osborn@uea.ac.uk>
>Subject: Re: IPCC AR4
>Date: Tue, 7 Jun 2005 10:36:45 +0100
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>Morning Tim,
>Indeed, the data I sent you were the time-series generated from the simple 
>regression calibration
>However, the data in Figure 3B are scaled time series. I mentioned it in 
>the caption of that figure.
>
>Essentially I used the regression based calibration to undertaken 
>verification and generate the error bars.
>Although verification could be made using scaled series, I could not 
>generate error bars with scaling.
>
>So which version to use? I think the scaled one likely would better 
>portray a better estimate of temperature amplitude.
>However, this is really only a gut feeling and has certainly not been tested.
>
>I have essentially used the same methodology for the coral paper and 
>Philip Brohan is generating a pseudo-proxy data-set with which I can test 
>regression vs. scaling procedures. This might become a part II paper, 
>depending on the results.
>
>re. my Figure 4 - I scaled all recons and models as I felt it was the 
>better method of comparison. I am not sure if others would agree, but as 
>the models show higher variance than the instrumental data and most recons 
>lower, I need to scale them all so I was comparing apples with apples with 
>regards to past temperature amplitude change.
>
>Hope this clarifies everything
>Rob
>
>PS. between you and me, I don't think our new NH recon really adds 
>anything new expect perhaps the fact that we should not put too much 
>confidence in these recons prior to 1100 or so. After seeing Ulrich 
>Cubasch's talk on the 32 flavours of climate, I think the whole 
>methodology is up in the air as well. Do you know if he has drafted a 
>paper on this work yet?
>
>----- Original Message -----
>From: <mailto:t.osborn@uea.ac.uk>Tim Osborn
>To: <mailto:rjwilson_dendro@blueyonder.co.uk>Rob Wilson
>Sent: Tuesday, June 07, 2005 10:07 AM
>Subject: Re: IPCC AR4
>
>Hi Rob,
>
>I haven't been able to reproduce figure 3B in your paper then.  This is
>labelled as anomalies wrt 1961-1990 and thus if I plot the data you sent
>for "RCS recon" "unfilter calib" I expected to reproduce it.  In 3B there
>are numberous positive RCS values in the 20th century, yet only a handful
>in excel file you sent.
>
>I'm wondering whether this is because you calibrated the reconstructions
>using regression against instrumental temperatures - and that is the data
>you sent - but then you scaled to match the instrumental mean and variance
>- and that is the data in 3B.  Is this right?  If so, I'd need to know your
>view on which you would prefer to be presented in the IPCC figure -
>presumably you prefer the scaled version, since that's what you show in the
>figures of the paper.  But you also scale all the others for comparison
>(figure 4A), whereas we've decided with discussion from the other chapter
>authors to stick with original calibrations.  So please let me know if I'm
>right about reasons why I can't reproduce your figure 3B and if so which
>version you and Rosanne prefer to show.
>
>I'm also a little unclear why you would regress and then rescale, since the
>latter would yield the same results as rescaling the original series
>wouldn't it?  Or was it a multiple regression?  Sorry, I've only read your
>paper once and didn't pick up on this yet!  Still, this is more a
>scientific issue and the question about the IPCC figure is the more important.
>
>Cheers
>
>Tim
>
>PS. Will get comments to you about the coral work very soon!
>
>
>
>
>
>
>At 20:54 06/06/2005, you wrote:
> >Hi Tim,
> >they are anomalies relative to the 1961-1990 mean, although remember
> >calibration was made over the 1856-1978 period. Therefore, the 1961-1990
> >mean of the reconstructed series will likely not be zero - in fact due to
> >the divergence, the are slightly lower.
> >
> >regards
> >Rob
> >
> >
> >----- Original Message -----
> >From: <<mailto:t.osborn@uea.ac.uk>Tim>mailto:t.osborn@uea.ac.uk>Tim Osborn
> >To: 
> <<mailto:rjwilson_dendro@blueyonder.co.uk>Rob>mailto:rjwilson_dendro@blueyonder.co.uk>Rob 
> Wilson
> >Cc: 
> <<mailto:K.briffa@uea.ac.uk>K.briffa@uea.ac.uk>mailto:K.briffa@uea.ac.uk>K.briffa@uea.ac.uk
> >Sent: Monday, June 06, 2005 3:43 PM
> >Subject: Re: IPCC AR4
> >
> >Hi Rob - thanks very much for the data.  One question - I'm using the
> >unfiltered RCS calibated data - what are they anomalies from?  The
> >1961-1990 mean, or the calibration period mean?  Cheers, Tim
> >
> >At 08:32 04/06/2005, Rob Wilson wrote:
> > >Hi Tim and Keith,
> > >I have attached the two NH reconstructions we have developed (STD and RCS
> > >versions).
> > >
> > >I am also sending the original paper to give you more information if need
> > >be. Unfortunately, and not surprisingly I guess, we heard yesterday that
> > >it was rejected from Nature. We are currently editing for submission to
> > >another Journal next week - under debate as to which.
> > >
> > >2 sigma error bars are provided for both the unfiltered reconstruction and
> > >the 20 yr spline version (i.e. see Figures 2a and 2b in the supplementary
> > >material).
> > >
> > >Please Note: The smoothed error bars were generated only as a guide for
> > >the confidence of the lower frequency signal - I re-did the calibration
> > >using smoothed series for each nested model. The resulting smoothed
> > >reconstruction therefore does not overlay perfectly upon the unfiltered
> > >reconstruction. In all analyses in the paper, I used the unfiltered
> > >reconstructions or low pass filtered versions of them.
> > >
> > >if you have any questions please feel free to e-mail or phone.
> > >regards
> > >Rob
> > >
> > >
> > >----- Original Message -----
> > >From:
> > 
> <<<mailto:druidrd@ldeo.columbia.edu>Rosanne>mailto:druidrd@ldeo.columbia.edu>Rosanne>mailto:druidrd@ldeo.columbia.edu>Rosanne>mailto:druidrd@ldeo.columbia.edu>Rosanne 
>
> > D'Arrigo
> > >To: 
> <<<mailto:t.osborn@uea.ac.uk>Tim>mailto:t.osborn@uea.ac.uk>Tim>mailto:t.osborn@uea.ac.uk>Tim>mailto:t.osborn@uea.ac.uk>Tim 
> Osborn
> > >Cc:
> > 
> <<<mailto:rjwilson_dendro@blueyonder.co.uk>rjwilson_dendro@blueyonder.co.uk>mailto:rjwilson_dendro@blueyonder.co.uk>rjwilson_dendro@blueyonder.co.uk>mailto:rjwilson_dendro@blueyonder.co.uk>rjwilson_dendro@blueyonder.co.uk>mailto:rjwilson_dendro@blueyonder.co.uk>rjwilson_dendro@blueyonder.co.uk
> > >Sent: Friday, June 03, 2005 2:44 PM
> > >Subject: Re: IPCC AR4
> > >
> > >hi Tim,
> > >
> > >Greetings. its is fine with me to show figures from our nh paper, which
> > >we are submitting shortly. I am ccing to Rob Wilson who can send you the
> > >data for the figures.
> > >
> > >cheers,
> > >Rosanne
> > >
> > >
> > >
> > >
> > > >Dear Rosanne,
> > > >
> > > >As you probably know, Keith Briffa has the job of putting together
> > > >the section on the climate of the last 2000 years for the next draft
> > > >of the IPCC Paleoclimate chapter.  I'm helping out with some
> > > >comments and figures - in particular, I am preparing a diagram
> > > >showing various TAR and post-TAR reconstructions of NH temperature.
> > > >
> > > >I contacted Ed Cook to get the updated calibration of the Esper et
> > > >al. reconstruction, which he provided.  But Ed also suggested that I
> > > >contact you because you have a new tree-ring based NH temperature
> > > >series in the pipeline.
> > > >
> > > >I'm not sure what stage it's at, but if it's appropriate would you
> > > >be willing to have it included in an IPCC comparison diagram?  To be
> > > >included, a paper describing it would need to have been accepted for
> > > >publication by December.
> > > >
> > > >Please let me know what you would like me to do: include it or not?
> > > >
> > > >If yes, then the data that I'd need are:
> > > >(1) the calibrated NH temperature reconstruction (plus an indication
> > > >of the reference period)
> > > >(2) uncertainty ranges for the calibrated series, if you have them,
> > > >at an appropriate time scale (e.g. for 30 year smoothed data)
> > > >
> > > >Best regards
> > > >
> > > >Tim
> > > >Dr Timothy J Osborn
> > > >Climatic Research Unit
> > > >School of Environmental Sciences, University of East Anglia
> > > >Norwich  NR4 7TJ, UK
> > > >
> > > >e-mail:
> > 
> <<<mailto:t.osborn@uea.ac.uk>t.osborn@uea.ac.uk>mailto:t.osborn@uea.ac.uk>t.osborn@uea.ac.uk>mailto:t.osborn@uea.ac.uk>t.osborn@uea.ac.uk>mailto:t.osborn@uea.ac.uk>t.osborn@uea.ac.uk
> > > >phone:    +44 1603 592089
> > > >fax:      +44 1603 507784
> > > >web:
> > 
> <<<http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/
> > > >sunclock:
> > >
> > 
> <<<http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm
> > >
> > >
> > >
> >
> >Dr Timothy J Osborn
> >Climatic Research Unit
> >School of Environmental Sciences, University of East Anglia
> >Norwich  NR4 7TJ, UK
> >
> >e-mail: 
> <<mailto:t.osborn@uea.ac.uk>t.osborn@uea.ac.uk>mailto:t.osborn@uea.ac.uk>t.osborn@uea.ac.uk
> >phone:    +44 1603 592089
> >fax:      +44 1603 507784
> >web: 
> <<http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/
> >sunclock:
> ><<http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~t 
> imo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm
>
>Dr Timothy J Osborn
>Climatic Research Unit
>School of Environmental Sciences, University of East Anglia
>Norwich  NR4 7TJ, UK
>
>e-mail:   <mailto:t.osborn@uea.ac.uk>t.osborn@uea.ac.uk
>phone:    +44 1603 592089
>fax:      +44 1603 507784
>web:      <http://www.cru.uea.ac.uk/~timo/>http://www.cru.uea.ac.uk/~timo/
>sunclock: 
><http://www.cru.uea.ac.uk/~timo/sunclock.htm>http://www.cru.uea.ac.uk/~timo/sunclock.htm

Dr Timothy J Osborn
Climatic Research Unit
School of Environmental Sciences, University of East Anglia
Norwich  NR4 7TJ, UK

e-mail:   t.osborn@uea.ac.uk
phone:    +44 1603 592089
fax:      +44 1603 507784
web:      http://www.cru.uea.ac.uk/~timo/
sunclock: http://www.cru.uea.ac.uk/~timo/sunclock.htm

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