Monday, April 9, 2012

3220.txt

date: Thu Feb 3 10:04:30 2005
from: Phil Jones <p.jonesatXYZxyz.ac.uk>
subject: Some comments
to: Anders Moberg <andersatXYZxyzu.su.se>

Anders,

I thought I should send am email to clear my mind. I have spoken to the German
correspondent from Nature, about your paper and also about MM. I spoke briefly about
MM, saying their paper was so off the wall it shouldn't really be considered in the same
story. I stressed the other series - not just MBH or MJ, and pointed out that of all these
(so your new one, Esper, Keith's, mine, Crowley's, MBH, MJ and GCM ones like Hans') all
show the 15th relatively cold. The ironic point for MM is that the closest (but it is
still
far away) to their series is MBH. So your paper coming out at this time is good in a way
as their work can easily be shown to be so wrong.
The German Nature correspondent who called yesterday (he said he would send back
any quotes he'll use today or tomorrow) wanted to make a big thing of IPCC and MBH, but
I kept on saying to him that this isn't the point. IPCC isn't the issue here and you seem
to
have been taken in by the skeptic media hype on this. What the temperature was or wasn't
over the millennium doesn't influence politicians and has nothing whatsoever to do with
Kyoto, which was written before MBH98 came out.
I also feel that you've gone overboard
about tree-ring standardization. Problems exist with all other proxies, it is just that
dendro
types are more open about these. No natural archives ensure an accurate reconstruction
- this is your phrase (accurate reconstruction) but for all measures I know trees are the
most widespread proxy and the second best (behind documentary) with all these measures.
I believe that the dating errors in some of the low-frequency series you've used are
too intolerable to be used. It is also virtually impossible to show whether they do
respond to
past temperature variations.
As with all Nature figures, the plots are so small it is difficult to make the series
out. Ch 6
of the current IPCC AR4 draft has plots of all the possible series (proxy on one series
of plots and model simulations on another). Tim Osborn here has produced the plot. In the
next month or so, it would be good if you could send your series to Tim (and also to me)
and he can add it to the plot for the next draft. I reckon your plot would look very like
Esper's
series, but would go back to AD 1. Over the period from 1 to AD 900 your plot, MJ and
Keith's series from QSJ in 2000 would be at much the same level. The whole issue is
about the amplitude over the last 1000 years. Maybe your series will be in the
supplementary
information ?
By the way on the model simulation plot, it is the ECHO-G model that is at odds with
all the other models, especially with the new NCAR GCM simulation. I would be careful
about ECHO-G. DMI have run the same model with slightly different forcing from 1500 and
get quite a different NH series.
Finally, the other thing that I know is wrong with your series is that is just has to
be
too low in the 1500-1750 period. I need to do lots more work to prove this, but this is
my gut feeling. There are periods in the early instrumental (1730s) and in documentary
series (for both Europe and China - some decades in the 1500s) that are relatively mild.
I know the evidence only comes from 2 locations, but if Europe and China were warm
the odds are that a lot of other places were also warm (little sea ice off Iceland etc).
So
I reckon you should have some years (maybe 20 in total) much closer to the 1961-90 period
between
1500-1750. ENSO years will pull it very close as it did in 1877/78. Your level in the
period 900-1100 is much closer to what my gut feeling is to as where it should be.
Maybe you don't have enough high-freq proxies in that part of the spectrum (for
1500-1750).
Well, I've said what I wanted to say. I can get back to all the non-paleo work I
have to do and we can get on with the rest of EMULATE.
Cheers
Phil

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
NR4 7TJ
UK
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