Sunday, January 15, 2012

1944.txt

date: Fri Jun 3 15:15:47 2005
from: Phil Jones <p.jonesatXYZxyz.ac.uk>
subject: Re: 1816 tropical SSTs
to: "Rob Wilson" <rjwilson_dendroatXYZxyzeyonder.co.uk>

Rob,
I seem to have gotten the coral paper anyway ! I'll have a look at it as I'm away next
week.
When I was including coral in the 1998 paper it was length we were looking for rather
than numbers. There are more now. Correlations with SST can be difficult because
of the quality of the SST data for some regions for some periods. I tended to go for
a reasonable size box where the coral's from, to avoid basing it on a single box.
The GBR stuff from Janice Lough was the best, but then that was several corals
anyway. We had trouble getting the Galapagos to correlate.
Cheers
Phil
At 09:22 03/06/2005, you wrote:

Morning Phil,
no the Nature paper is a TR based NH extra-tropical temperature reconstruction that I
wrote with Rosanne D'Arrigo.
Essentially a substantial update (1250 years in length) to the original Jacoby and
D'Arrigo work.

The coral paper is a different beast. I am leaning towards JGR for submission as I don't
think it has the restrictive word length of GRL.

I can send you the last draft of the coral paper if you like, although I hope to tighten
it in the next week or so.

For the coral reconstruction, I did not include the New Caledonia data.
I set up a fairly stringent screening procedure for the coral data - i.e. only those
series that correlated significantly with local annual SSTs using both unfiltered and
1st differenced time-series were used for later analysis.

The new Caledonia data did not pass this test. This is, in fact, a problem with many of
the coral data-sets - the long term trends in these data might be related to salinity
changes rather than SST. However, due to strong linear trends, there is often a
reasonable correlation with local SST using unfiltered series, which is purely an
artefact of trend. Hence my use of 1st difference transforms to identify a 'pure'
temperature signal. The new Caledonia data did not correlate significant with local SSTs
at these high frequencies - hence, using my empirical approach, I could not rationalise
the record to be a true temperature proxy.
Although a strict interpretation of the new Caledonia O18 record as a temperature proxy
would indicate cooler conditions around the 1810-1820 period, I do not think such an
interpretation is entirely correct. Also, through this period, the lowest index value is
1814, not 1816. 1885 is an inferred cool year which could tie in nicely with Krakatoa
however.
It is also interesting to note that many of the coral records utilised by Mike Mann also
failed my screening procedure.

The attached figure shows normalised series of the 5 coral records that go back to 1801
in my 'SST sensitive' data-set. The y-axis has been inverted as the series are
negatively correlated to SSTs.
Only one record (MAL = Malindi: western Indian Ocean - Julia Cole) shows an inferred
cool year in 1816.

As I state in the paper - lots of potential for corals, but there is simply not enough
data prior to 1850 to derive particularly robust reconstructions.

just say if you want a copy of the paper
hope this helps
best regards
Rob


----- Original Message -----

From: [1]Phil Jones
To: [2]Rob Wilson
Sent: Thursday, June 02, 2005 3:48 PM
Subject: Re: 1816 tropical SSTs
Rob,
Nice diagram ! Is this in the Nature submission you were talking to Keith about
this morning.
I'd put more faith in the few corals at this time the ships. I think corals have
juvenile
problems like trees. Is any of Crowley's corals from the New Caledonia region in
the coral set. Tom makes a big thing of their cooling in the 1810s.
Cheers
Phil
At 15:11 02/06/2005, you wrote:

Dear Michael,
Last week, from a BBC Timewatch documentary, I was very interested to learn about
your research on historical temperatures in the year after the Tambora eruption.

Phil Jones sent me your e-mail address so I could contact you. I am working with
Keith Briffa and have been using coral isotopic records to reconstruct annual
tropical SSTs for the last few centuries. A paper will be submitted on this work in
the next few weeks.

One of the observations that our reconstruction shows is that tropical SSTs were not
particularly anomalous around 1816 - see attached figure. We are wondering if your
results agree or disagree with our observation.

Unfortunately, there are only a few coral records that go back to the early 19th
century, so the fact that we do not identify cool SSTs in 1816 might reflect the
spatial bias in our coral record network. However, teak tree-ring chronologies from
Indonesia also do not show anomalous growth departures for this period.

Do you per chance have any spatial maps of SSTs for this year?
I would also be interested in any articles you have written (or that are in
preparation) with regards to 1816.

I hope you can help

best regards
Rob
-----------------------------------------------------------------------
Dr. Rob Wilson
Honorary Research Fellow
School of GeoSciences,
Grant Institute,
Edinburgh University,
West Mains Road,
Edinburgh EH9 3JW,
Scotland, U.K.
Tel: 0131 620 1141

Publication PDFs: [3]http://www.robdendro.pwp.blueyonder.co.uk/publications.html

".....I have wondered about trees.

They are sensitive to light, to moisture, to wind, to pressure.
Sensitivity implies sensation. Might a man feel into the soul of a tree
for these sensations? If a tree were capable of awareness, this faculty
might prove useful. "

"The Miracle Workers" by Jack Vance
-----------------------------------------------------------------------

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
----------------------------------------------------------------------------

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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