date: Tue May 4 11:39:04 2004
from: Phil Jones
subject: Re: East African data
to: "David J. Thomson"
David,
Neither Keith Briffa nor I know of long paleo series for the Nile Basin. We also
agree with you about the nonsense of a lot of the stuff on long cycles. Whilst
you're working in this can you dispose of the Hurst phenomenon at the same
time ! Heard some appalling talks on this in a session I stumbled on at the
EGU.
We have a lot of long daily series - look at the CRU web page (EMULATE project).
I can send some of these when you have some time to look at them.
Not coming to AGU - been away for the last 3 weeks, a mountain of email !
Cheers
Phil
At 11:44 23/04/2004 -0400, you wrote:
Phil,
A student of mine, Scott Amiss, has been working on the Nile
annual minimum levels (622 to 1284 AD). As you are probably aware, there
has been a lot of stuff in the statistics literature using this data (plus
your NH average temperature, etc.) as examples of ``long memory''
processes.
My feeling (and Scott's) is that the long memory stuff is mostly
statistical nonsense. (To be fair, it does have some persistent features
but the 18.6-year lunar cycle and the 208-year Suess wiggles are in a
different category than ``fractionally integrated brownian noise''.)
One of our goals is to attempt to restore some sanity to the
statistics literature...
The reason for writing is that Scott was looking for East
African climate data that overlaps or extends the Nile record;
so I was wondering if you have tree-ring or other proxy data from
this part of the world, or know who does.
I haven't forgotten your comments on the new European daily
tmperature data, so will likely ask you for these one of these days.
Apart from this, hope all is well, and that you had a better
winter than the NE US and Canada did this year. Here it was cold but,
fortunately, we didn't have it as bad as Boston, NY, or the Marimimes.
I'm up to my ears building the solar radio telescope,
trying to sort out solar and space data, trying to write a book,
working on tuning on some of the longer paleo records, etc...
Are you coming over to Spring AGU? If so, see you there.
Otherwise, if you get over this way, let us know and plan on a
visit.
Cheers
David Thomson
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.jones@uea.ac.uk
NR4 7TJ
UK
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