The below are part of a series of alleged emails from the Climate Research Unit at the University of East Anglia, released on 20 November 2009.
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From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: jto@u.arizona.edu,eystein.jansen@xxxxxxxxx.xxx,tcrowley@xxxxxxxxx.xxx
Subject: thoughts and Figure for MWP box
Date: Mon Jul 18 17:12:xxx xxxx xxxx
Dear Peck, Eystein and Tom
At this point we thought it was important to review where we think we are with the MWP
Figure.
First, we have no objection to a Figure . Our only concerns have been that we should
1/... be clear what we wish this Figure to illustrate (in the specific context of the MWP
box) - note that this is very different from trying to produce a Figure in such a way as to
bias what it says (I am not suggesting that we are, but we have to guard against any later
charge that we did this). We say this because there are intonations in some of Peck's
previous messages that he wishes to "nail" the MWP - i.e. this could be interpreted as
trying to say there was no such thing, and
2/ ...agree that we have done this in the best way.
The truth is that there IS a period of relative warmth around the end of the 1st and start
of the 2nd millennium C.E. , but that there are much fewer data to base this conclusion on
(and hence the uncertainty around even our multiple calibrated multi-proxy reconstructions
are wide). The geographical spread of data also impart a northern (and land) bias in our
early proxy data. My understanding of Tom's rationale with the Figure is that we should
show how, because the timing of maximum pre-20th century warmth is different in different
records, the magnitude of the warmest period (for the Hemisphere , or globe, as a whole) is
less than the recently observed warmth.
The reconstructions we plot in Chapter 6 already express the mean Hemispheric warmth (after
various selection and scaling of data), and so the additional information that the MWP box
figure should show must relate to the scatter of the proxy data. There seems to be a
consensus that this is best done by showing individual records , and we are happy to agree.
What we worry very much about, however, is that we should not produce a Figure that then
conflicts with the picture of proxy evidence for Hemispheric mean warmth as a whole,shown
in the main Chapter Figure. By showing a composite (as Tom has done) and scaling against
another (30-90degrees N) temperature record - this is just what is done.
As we promised, Tim has produced a similar Figure, using the same series plus a few extras,
but omitting the composite mean and the scaling against instrumental temperatures. The idea
was to include as many of the original input series (to the various reconstructions) as we
could - though avoiding conflicting use of different versions of the same data. The
precise selection of records will have to be agreed and, presumably, based on some clear,
objective criteria that we would need to justify (this will not be straight forward). This,
along with Tom's plot (forwarded by Peck) is in the attachment.
We would like to get your opinion now, and especially Tom's, on the points regarding the
composite and scaling. We would be in favour of just showing the series - but do they make
the point (and emphasise the message of the text in the box)? Or does the scatter of the
various series as plotted, dilute the message about the strength of 20th century mean
warming (note the apparently greater scatter in the 20th century in our figure than in
Tom's)? Can you all chip in here please.
best wishes
Keith and Tim
P.S. We agreed in Beijing that we should definitely ask Tom to be a CA .
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
Original Filename: 1121869083.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: Tim Osborn <t.osborn@xxxxxxxxx.xxx>
Subject: Fwd: Re: thoughts and Figure for MWP box
Date: Wed Jul 20 10:18:xxx xxxx xxxx
Date: Tue, 19 Jul 2005 15:38:31 +0100
To: Tom Crowley <tcrowley@xxxxxxxxx.xxx>, Jonathan Overpeck <jto@u.arizona.edu>
From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Re: thoughts and Figure for MWP box
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
Tom et al
thanks for remarks - in response to Tom's questions
At 18:23 18/07/2005, Tom Crowley wrote:
a few comments -
1) are you trying to choose between my way of presenting things and your way - ie, w
w/out composite?
Yes
2) with your data, do they all go through from beginning to end?
pretty much - and have been standardised over the maximum period for each (not
necessarily the best way?)
3) why include chesapeake, which is likely a salinity record?
Because Moberg used it in their latest reconstruction - I agree that I would not use it
because of the dubious temperature signal (salinity effect and no local replication) and
poor dating control (and I do not like the way the Moberg method effectively over
weights the low-frequency predictor series in their analysis).
4) some of your data are from virtually the same site - Mangazeja and yamal are both w.
siberia - I composited data available from multiple sites to produce one time series,
which is equally counted against the other regions, which might (greenland, w.U.S., e.
Asia) or might not have multiple records in them
Just to reiterate - I understood after the group chat with Susan S. in Beijing , that we
were being asked to try to produce a "cloud" diagram including as many of "original"
predictor series ,from all the reconstructions, to see if it provided an "obvious"
picture of the unprecedented warming over the last millennium or so. Tim and I are in no
way trying t produce a different Figure for the sake of producing a different Figure .
In practice this is hard to do (because some records are sensible "local" composites
already, and how far do you go in showing all input data? The problem of what and how to
composite is tricky - and no obviously "correct" way is apparent.
Having said this , Tom's way is fine with me (provided the composites are robust) and we
get general agreement. Am happy to go with Tom's Figure , or version that incorporates
as many records as possible - but as we have said - without the composite or temperature
scaled add ons.
5) I am not sure whether it is wise to add me to the CA list, just because the reviewer
is supposed to be impartial and a CA loses that appearance of impartiality if he has now
been included as a CA - may want to check with Susan S. on this one to be sure - still
happy to provide advice
My own position on this is that you are an "unofficial" referee, who has (and still is)
making a significant contribution - I see no conflict
6) I am happy to go in either direction - include or not include my figure - all I need
are specific directions as to what to do, as CLAs you people need to decide, and then
just tell me what or what not to do
Agree - CLAs please rule on the individual record/composite question - I am very happy
to go with Tom's Figure. We did ours because we were asked to.
7) I am a little unhappy with the emphasis on hemispheric warmth - lets face it, almost
all of the long records are from 30-90N - the question is: how representative is 30-90N
to the rest of the world? for the 20th c. one can do correlations with the instrumental
record, but co2 has almost certainly increased the correlation scale beyond what it was
preanthropogenic.
Absolutely agree , and hope this comes over in text (and bullets) - if not needs
strengthening (note David R's comments).
you could correlate with quelcaya - not sure how many other records there are that are
annual resolution - in the tropics I have produced a tropical composite (corals +
Quelc.) but it only goes back to ~1780 - corals just don't live v long - in that
interval at least the agreement is satisfactory with the mid latitude reconstruction but
there is only 100 years extra of independent information beyond the instrumental
record..
We have gone round in circles over this , but understand consensus to be that Quelc. not
a clean temperature record. Agree corals would be better longer (the new coral-based
reconstruction by Rob Wilson et al
goes back to 1700 and shows unprecedented tropical warming . Along with the text from
Julie we can not go much further, but the importance of extending the tropical (and SH
records needs to be very clear)
.THIS MAY NEED TO BE ADDRESSEDAS A GENERAL ISSUE SOMEWHERE (SHORTLY) IN YOUR DOC
Really hope it is already - but advise if you think not
tom
Thanks for this - lets take lead from J and E now (also can you advise on state of play
with the Hegerl et al manuscript?)
thanks
Keith
Jonathan Overpeck wrote:
Hi Keith, Eystein and Tom: See below (BOLD) for my comments. Thanks for moving this
forward and making sure we do it right (i.e., without any bias, or perception of bias).
Dear Peck, Eystein and Tom
At this point we thought it was important to review where we think we are with the MWP
Figure.
First, we have no objection to a Figure . Our only concerns have been that we should
1/... be clear what we wish this Figure to illustrate (in the specific context of the
MWP box) - note that this is very different from trying to produce a Figure in such a
way as to bias what it says (I am not suggesting that we are, but we have to guard
against any later charge that we did this). We say this because there are intonations in
some of Peck's previous messages that he wishes to "nail" the MWP - i.e. this could be
interpreted as trying to say there was no such thing, and
SORRY TO SCARE YOU. I **ABSOLUTELY** AGREE THAT WE MUST AVOID ANY BIAS OR PERCEPTION OF
BIAS. MY COMMENT ON "NAILING" WAS MADE TO MEAN THAT ININFORMED PEOPLE KEEPING COMING
BACK TO THE MWP, AND DESCRIBING IT FOR WHAT I BELIEVE IT WASN'T. OUR JOB IS TO MAKE IT
CLEAR WHAT IT WAS WITHIN THE LIMITS OF THE DATA. IF THE DATA ARE NOT CLEAR, THEN WE HAVE
TO BE NOT CLEAR. THAT SAID, I THINK TOM'S FIGURE CAPTURED WHAT I HAVE SENSED IS THE MWP
FOR A LONG TIME, AND BASED ON OTHER SOURCES OF INFO - INCLUDING KEITH'S PROSE. THE IDEA
OF A FIGURE, IS THAT FIGURES CAN BE MORE COMPELLING AND CONNECT BETTER THAN TEXT. ALSO,
THERE ARE MANY WAYS TO LOOK AT THE MWP, AND AS LONG AS WE DON'T INTRODUCE BIAS OR
ANYTHING ELSE THAT WILL DILUTE THE MESSAGE IN THE END, THE IDEA IS TO SHOW THE MWP IN
MORE WAYS THAN TWO (THAT IS, THE EXISTING FIGS IN THE TEXT THAT KEITH AND TIM MADE).
2/ ...agree that we have done this in the best way.
The truth is that there IS a period of relative warmth around the end of the 1st and
start of the 2nd millennium C.E. , but that there are much fewer data to base this
conclusion on (and hence the uncertainty around even our multiple calibrated multi-proxy
reconstructions are wide). The geographical spread of data also impart a northern (and
land) bias in our early proxy data.
NEED TO BE CLEAR ABOUT THIS BIAS IN THE CAPTION AND BOX TEXT
My understanding of Tom's rationale with the Figure is that we should show how, because
the timing of maximum pre-20th century warmth is different in different records, the
magnitude of the warmest period (for the Hemisphere , or globe, as a whole) is less than
the recently observed warmth.
YES, BUT IN A WAY THAT SAYS "LOOK, HERE ARE THE ACTUAL REGIONAL CURVES - CHECK IT OUT
FOR YOURSELF" INSTEAD OF JUST SAYING (IN A SCIENTIFICALLY MORE STANDARD MANNER - HERE
ARE THE VARIOUS, MOST ROBUST, LARGE AREA RECONSTRUCTIONS. IN MY MIND, THE LATTER
(KEITH/TIM FIGS IN THE MAIN TEXT) WILL BE THE MOST APPEALING/CONVINCING TO PALEOCLIMATE
SCIENTISTS, BUT TOM'S MIGHT HELP THERE, AND CERTAINLY WITH NON-PALEO SCIENTISTS AND
POLICY FOLKS. MIGHT HELP... IF IT DOESN'T NOTHING LOST, BUT IF IT COULD HURT CONVEYING
UNDERSTANDING, THEN ITS BAD TO USE THE NEW FIGURE.
The reconstructions we plot in Chapter 6 already express the mean Hemispheric warmth
(after various selection and scaling of data), and so the additional information that
the MWP box figure should show must relate to the scatter of the proxy data. There seems
to be a consensus that this is best done by showing individual records , and we are
happy to agree.
What we worry very much about, however, is that we should not produce a Figure that then
conflicts with the picture of proxy evidence for Hemispheric mean warmth as a
whole,shown in the main Chapter Figure. By showing a composite (as Tom has done) and
scaling against another (30-90degrees N) temperature record - this is just what is done.
ABSOLUTELY RIGHT - CAN'T HAVE CONFLICT.
As we promised, Tim has produced a similar Figure, using the same series plus a few
extras, but omitting the composite mean and the scaling against instrumental
temperatures. The idea was to include as many of the original input series (to the
various reconstructions) as we could - though avoiding conflicting use of different
versions of the same data. The precise selection of records will have to be agreed and,
presumably, based on some clear, objective criteria that we would need to justify (this
will not be straight forward). This, along with Tom's plot (forwarded by Peck) is in the
attachment.
We would like to get your opinion now, and especially Tom's, on the points regarding the
composite and scaling. We would be in favour of just showing the series - but do they
make the point (and emphasise the message of the text in the box)? Or does the scatter
of the various series as plotted, dilute the message about the strength of 20th century
mean warming (note the apparently greater scatter in the 20th century in our figure than
in Tom's)? Can you all chip in here please.
best wishes
WHAT ABOUT THE IDEA THAT WE ONLY SHOW THE SERIES FOR THE MWP, SINCE THE COMPARISON TO
THE 20TH CENTURY IS DONE WELL (AND BEST?) IN THE TEXT FIGS (WHICH I'M ATTACHING JUST IN
CASE TOM DOESN'T HAVE, ALONG WITH THE TEXT - IF YOU HAVE TIME, TOM, PLEASE READ COMMENT
ON ANYTHING YOU WISH, BUT CERTAINLY THE LAST 2000 YEARS BIT - ASSUME YOU'LL BE DOING
THIS AT THE REVIEW STAGE ANYHOW...)
ANOTHER THING THAT IS A REAL ISSUE IS SHOWING SOME OF THE TREE-RING DATA FOR THE PERIOD
AFTER 1950. BASED ON THE LITERATURE, WE KNOW THESE ARE BIASED - RIGHT? SO SHOULD WE SAY
THAT'S THE REASON THEY ARE NOT SHOWN? OF COURSE, IF WE ONLY PLOT THE FIG FROM CA 800 TO
1400 AD, IT WOULD DO WHAT WE WANT, FOCUS ON THE MWP ONLY - THE TOPIC OF THE BOX - AND
SHOW THAT THERE WERE NOT ANY PERIODS WHEN ALL THE RECORDS ALL SHOWED WARMTH - I.E., OF
THE KIND WE'RE EXPERIENCING NOW.
TWO CENTS WORTH
Keith and Tim
P.S. We agreed in Beijing that we should definitely ask Tom to be a CA .
TRUE - BUT HAS ANYONE CONFIRMED W/ TOM. TOM, YOU OK W/ THIS?
THANKS - A GREAT DISCUSSION, AND LETS SAY THE JURY IS STILL OUT ON THIS FIGURE UNTIL WE
ALL ARE COMFORTABLE WITH WHAT IT LOOKS LIKE IN THE END.
BEST, PECK
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
Attachment converted: Macintosh HD:mwpbox_figures.pdf (PDF /
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From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: Tim Osborn <t.osborn@xxxxxxxxx.xxx>
Subject: Fwd: Re: the regional section and MWP Figure
Date: Wed Jul 20 11:03:xxx xxxx xxxx
From: "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>
To: "Jonathan Overpeck" <jto@u.arizona.edu>,
"Edward R. Cook" <drdendro@xxxxxxxxx.xxx>
Cc: "Keith R. Briffa" <k.briffa@xxxxxxxxx.xxx>,
<eystein.jansen@xxxxxxxxx.xxx>
Subject: Re: the regional section and MWP Figure
Date: Tue, 19 Jul 2005 15:35:xxx xxxx xxxx
X-Mailer: Microsoft Outlook Express 6.00.2800.1437
Dear Keith and Ed,
Please, find attached the new version of the SH figure for the IPCC. I have
now included the New Zealand record. All the records have been scaled to 4
Original Filename: 1121875880.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: David Rind <drind@xxxxxxxxx.xxx>
To: Stefan Rahmstorf <rahmstorf@xxxxxxxxx.xxx>
Subject: Re: [Wg1-ar4-ch06] Comments on Section 6.3
Date: Wed, 20 Jul 2005 12:11:xxx xxxx xxxx
Cc: wg1-ar4-ch06@xxxxxxxxx.xxx
<x-flowed>
Dear Stefan,
The distinction here is that GCMs attempt to calculate from first
principles the zeroth and first order processes that dominate the
problem they are studying, whereas EMICs parameterize many of those
processes. The fact that EMICs can reproduce GCM results suggest that
their parameterizations have been tuned to do so - but this does not
in any way imply that if one alters the forcing or boundary
conditions outside of a small range, or apply them to completely
different problems, that the two types of models will react
similarly. In fact, there is a history of this - the first "EMICs"
had a very large sensitivity to a 2% solar insolation change; then
they had to be re-tuned to prevent that from happening. EMICs are
used for paleo-problems because of their ability to take large
time-steps, but there is no free lunch - in doing so, they sacrifice
calculating the fundamental physical processes the way the real world
does it. GCMs have storms, they have real water vapor transports,
they have winds calculated from solving the conservation of momentum
equation, etc. etc. There is a quantum difference between the
fundamental approaches - it is not a continuum, in which there are no
real differences, everything is simply a matter of opinion, there is
no such thing as truth - that's the argument that greenhouse
skeptics use to try to make science go away.
Because we can't use GCMs for long-time scale problems, we do the
best we can - we use these heavily parameterized models. If we could
use GCMs for those problems, EMICs could then be tuned to produce the
GCM results on those time-scales as well. But in this case we have no
way to validate the EMIC results - and since the first principles are
not being used, we cannot know whether they represent a physically
consistent solution or not. Therefore all they can do is suggest
interactions among processes, a useful though not definitive addition
to the field.
David
ps - concerning CLIMBER-2, I asked a number of leading climate
scientists to read the model description paper. Peter Stone was the
only person I asked who thought the model was at all useful for
studying the types of problems we are discussing. And it was not only
GCM scientists. If you want to hear further cogent arguments
concerning its inapplicability, consider contacting Bill Rossow (the
recent winner of a major honor as a leading climate scientist) but
make sure your email program or telephone accepts unexpurgated text.
At 4:22 PM +0200 7/20/05, Stefan Rahmstorf wrote:
>Dear David,
>
>I take from your response that you consider all models that
>parameterise an important first-order process "conceptual models". I
>can live with that - but then there are only conceptual climate
>models around. Any coupled climate GCM that I know of parameterises
>oceanic convection (and in a very crude way), hence it is a
>conceptual model in your terms, and there is no fundamental
>distinction of category between your model and our model.
>
>To me the scientific question is not whether an important process is
>parameterised (many are in GCMs) - it is how well this
>parameterisation works, for the task at hand. We have tested the
>feedbacks in great detail (e.g., the cloud, water vapour, lapse rate
>and snow/ice albedo feedbacks for 2xCO2) in our model and they
>perform quantitatively within the range simulated by various GCMs.
>The same is true for many other diagnostics - the model has taken
>part in model intercomparisons with GCMs and always falls within the
>range of different GCMs, in a quantitative way. To repeat that
>point, the quantitative differences between different GCMs are
>larger than the typical difference between our model and a GCM. So I
>see no basis for your claim that this model can only "suggest orders
>of magnitude". That's just plain wrong from all the evidence that I
>have seen (a lot). If you have concrete evidence to the contrary,
>other than just knowing one person who happens to agree with you,
>please come forward with it.
>
>Stefan
>
>--
>To reach me directly please use: rahmstorf@xxxxxxxxx.xxx
>(My former addresses @pik-potsdam.de are read by my assistant Brigitta.)
>
>Stefan Rahmstorf
>www.ozean-klima.de
>www.realclimate.org
_______________________________________________
Wg1-ar4-ch06 mailing list
Wg1-ar4-ch06@xxxxxxxxx.xxx
http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
</x-flowed>
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From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: Jonathan Overpeck <jto@u.arizona.edu>, Tom Crowley <tcrowley@xxxxxxxxx.xxx>
Subject: Re: CLA feedback on Tom and the MWP
Date: Wed Jul 20 12:18:xxx xxxx xxxx
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>,t.osborn@xxxxxxxxx.xxx
Hi all
think this is resolved now (virtually) -
We use series that total to Tom/Gabi composite , and we can cite this as an example of the
scatter of regional records "in a typical reconstruction". This avoids very difficult issue
of what is the best way to aggregate certain data sets - we are simply illustrating the
point with one published (by then) data set.
The issue of the composite is then not an issue either , because it is not a new
(unpublished) composite that we were concerned about - though I still believe it is a
distraction to put the composite in. It would be best to use data from 800 or 850 at least
, and go to 1500 (?) and presumably normalise over the whole period of data shown. OK? Even
though you guys all wish to go with the reduced period (ie not up the present) , but my own
instinct is that this might later come back to haunt us - but will take your lead.
I agree the look of the Figure should match the others.
So, if Tom will send the data sets (his regional curves) , Tim will plot and send back asap
for scrutiny. Thanks Tom and thanks for your help with this - further comments on latest
version of 6.5 (last 2000 years) still welcome , though will be incorporating a few changes
in response to David and Fortunat input , and SH bit (from Ricardo and Ed) still to go in
and regional section to be revised (after input from Peck et al.)
cheers
Keith
.
At 21:42 19/07/2005, Jonathan Overpeck wrote:
Hi Keith and Tim: Just got off the phone with Eystein, and hopefully he will sleep ok
knowing that we have a plan for the MWP fig and Tom...
Please ask questions if we don't cover all the key points, but here's what we think:
1) the MWP fig should span the MWP only, and should emphasize variation in regional
amplitude (we agree that we must be clear that this fig is not a reconstruction) - that
is, it is best to use time series representing regions, assuming that the regional
series do represent a region ok with one or more input series. We want to avoid a
regional bias if we can - this is what got us into all the MWP misunderstanding in the
first place, perhaps (e.g., nice MWP in Europe/Atlantic region - must be global)
2) If you guys could agree on the series and the interval, that'd be great. We agree it
would be good to start before 1000 and end before the Renaissance (15th century?). If
you want more feedback on these issues, we're happy to provide, but it seems logical
that you pick series and intervals so that each series covers the entire interval
selected.
3) Don't use the Chesapeak record - it is likely biased by salinity
4) We'd like Keith and Tim to draft the final figure so that it matches the look and
style of the other two figs they have made. Hope this is doable. Tom, does Keith have
all the data? Thanks for sending if not.
5) We agree that Tom should NOT be a CA given that he was officially one of the ZOD
reviewers. Of course, this doesn't represent a real conflict, but we need to avoid even
the appearance of conflict. We greatly appreciate all the feedback that Tom is
providing! Is this plan ok w/ you Tom? We think you're cool with it, but just want to
check one more time.
That... it is. Please let us know if there are any more questions. Keith - feel free to
try and get Eystein on his cell doing your work hours if you want quick feedback. Or we
can do this by email - he's not in a very email friendly place right now, but the
fishing appears to be ok.
Again, thanks to you both for all the discussion and thought that has gone into this
figure.
Best, peck
--
Jonathan T. Overpeck
Director, Institute for the Study of Planet Earth
Professor, Department of Geosciences
Professor, Department of Atmospheric Sciences
Mail and Fedex Address:
Institute for the Study of Planet Earth
715 N. Park Ave. 2nd Floor
University of Arizona
Tucson, AZ 85721
direct tel: xxx xxxx xxxx
fax: xxx xxxx xxxx
[1]http://www.geo.arizona.edu/
[2]http://www.ispe.arizona.edu/
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
[3]http://www.cru.uea.ac.uk/cru/people/briffa/
References
1. http://www.geo.arizona.edu/
2. http://www.ispe.arizona.edu/
3. http://www.cru.uea.ac.uk/cru/people/briffa/
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From: Stefan Rahmstorf <rahmstorf@xxxxxxxxx.xxx>
To: David Rind <drind@xxxxxxxxx.xxx>
Subject: Re: [Wg1-ar4-ch06] Comments on Section 6.3
Date: Wed, 20 Jul 2005 12:39:05 +0200
Cc: Eystein Jansen <Eystein.Jansen@xxxxxxxxx.xxx>
Dear chapter 6 friends,
I have a request on procedure. In the interest of a good and constructive working
atmosphere, I would suggest that all of us focus on sober scientific arguments and refrain
from unneccessarily derogatory comments about the work of colleagues. I'm referring in this
case to David's comment
- this reference is overused, especially for such a simplistic model
The reference concerned is our theory of DO events which appeared in Nature in 2001 and has
since been cited 133 times according to the Web of Science (a sign of overuse?) The model
concerned is the CLIMBER-2 model, featured in over 50 peer-reviewed publications since
1998, including 7 in Nature and Science.
This model is different from David's model, because it has been constructed for a
differenet purpose, but it is not "simplistic". It would never occur to me to call David's
model "simplistic" because it does not include an interactive continental ice sheet model,
vegetation model, carbon cycle model, sediment model and isotope model.
I'm absolutely open to any rational scientific criticism and discussion, but I can see no
purpose in derogatory statements like the above, which include not even a trace of
scientific argument. This kind of thing only poisons the working atmosphere in our group,
which I thought was very positive and a great pleasure in Beijing.
Regards, Stefan
--
To reach me directly please use: [1]rahmstorf@xxxxxxxxx.xxx
(My former addresses @pik-potsdam.de are read by my assistant Brigitta.)
Stefan Rahmstorf
[2]www.ozean-klima.de
[3]www.realclimate.org
_______________________________________________ Wg1-ar4-ch06 mailing list
Wg1-ar4-ch06@xxxxxxxxx.xxx http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
References
1. mailto:rahmstorf@xxxxxxxxx.xxx
2. http://www.ozean-klima.de/
3. http://www.realclimate.org/
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From: Jonathan Overpeck <jto@u.arizona.edu>
To: Tom Crowley <tcrowley@xxxxxxxxx.xxx>
Subject: Re: CLA feedback on Tom and the MWP
Date: Wed, 20 Jul 2005 14:23:xxx xxxx xxxx
Cc: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
<x-flowed>
Tom - thanks. Good points regarding regional labeling. Defn stick to
Tibetan Plateau!
best, peck
>Keith, if you can find more I see no problem - it seems that a lot
>of the data you used was via Cook and colleagues - I was unable to
>locate a full length record from Quebec in that time series, but
>maybe you are relying on something else - if so can I have it!?
>
>other suggestions: provide a more general label to sites - eg,
>mangazeyek (sp)/yamal could be listed as polar urals - taimyr
>central Siberia.
>
>China shoudl be relabeled as east Asia as it does include some
>information from Japan and the Tibetan Plateau (L. Thompson) and we
>don't want to get into some political to-do by calling Tibet
>"Chinese".
>
>that's all I can think of for present, good sailing, tom
>
>Keith Briffa wrote:
>
>>Hi all
>>think this is resolved now (virtually) -
>>
>>We use series that total to Tom/Gabi composite , and we can cite
>>this as an example of the scatter of regional records "in a typical
>>reconstruction". This avoids very difficult issue of what is the
>>best way to aggregate certain data sets - we are simply
>>illustrating the point with one published (by then) data set.
>>The issue of the composite is then not an issue either , because it
>>is not a new (unpublished) composite that we were concerned about -
>>though I still believe it is a distraction to put the composite in.
>>It would be best to use data from 800 or 850 at least , and go to
>>1500 (?) and presumably normalise over the whole period of data
>>shown. OK? Even though you guys all wish to go with the reduced
>>period (ie not up the present) , but my own instinct is that this
>>might later come back to haunt us - but will take your lead.
>>I agree the look of the Figure should match the others.
>>So, if Tom will send the data sets (his regional curves) , Tim will
>>plot and send back asap for scrutiny. Thanks Tom and thanks for
>>your help with this - further comments on latest version of 6.5
>>(last 2000 years) still welcome , though will be incorporating a
>>few changes in response to David and Fortunat input , and SH bit
>>(from Ricardo and Ed) still to go in and regional section to be
>>revised (after input from Peck et al.)
>>cheers
>>Keith
>>.
>>
>>
>> At 21:42 19/07/2005, Jonathan Overpeck wrote:
>>
>>>Hi Keith and Tim: Just got off the phone with Eystein, and
>>>hopefully he will sleep ok knowing that we have a plan for the MWP
>>>fig and Tom...
>>>
>>>Please ask questions if we don't cover all the key points, but
>>>here's what we think:
>>>
>>>1) the MWP fig should span the MWP only, and should emphasize
>>>variation in regional amplitude (we agree that we must be clear
>>>that this fig is not a reconstruction) - that is, it is best to
>>>use time series representing regions, assuming that the regional
>>>series do represent a region ok with one or more input series. We
>>>want to avoid a regional bias if we can - this is what got us into
>>>all the MWP misunderstanding in the first place, perhaps (e.g.,
>>>nice MWP in Europe/Atlantic region - must be global)
>>>
>>>2) If you guys could agree on the series and the interval, that'd
>>>be great. We agree it would be good to start before 1000 and end
>>>before the Renaissance (15th century?). If you want more feedback
>>>on these issues, we're happy to provide, but it seems logical that
>>>you pick series and intervals so that each series covers the
>>>entire interval selected.
>>>
>>>3) Don't use the Chesapeak record - it is likely biased by salinity
>>>
>>>4) We'd like Keith and Tim to draft the final figure so that it
>>>matches the look and style of the other two figs they have made.
>>>Hope this is doable. Tom, does Keith have all the data? Thanks for
>>>sending if not.
>>>
>>>5) We agree that Tom should NOT be a CA given that he was
>>>officially one of the ZOD reviewers. Of course, this doesn't
>>>represent a real conflict, but we need to avoid even the
>>>appearance of conflict. We greatly appreciate all the feedback
>>>that Tom is providing! Is this plan ok w/ you Tom? We think you're
>>>cool with it, but just want to check one more time.
>>>
>>>That... it is. Please let us know if there are any more questions.
>>>Keith - feel free to try and get Eystein on his cell doing your
>>>work hours if you want quick feedback. Or we can do this by email
>>>- he's not in a very email friendly place right now, but the
>>>fishing appears to be ok.
>>>
>>>Again, thanks to you both for all the discussion and thought that
>>>has gone into this figure.
>>>
>>>Best, peck
>>>--
>>>Jonathan T. Overpeck
>>>Director, Institute for the Study of Planet Earth
>>>Professor, Department of Geosciences
>>>Professor, Department of Atmospheric Sciences
>>>
>>>Mail and Fedex Address:
>>>
>>>Institute for the Study of Planet Earth
>>>715 N. Park Ave. 2nd Floor
>>>University of Arizona
>>>Tucson, AZ 85721
>>>direct tel: xxx xxxx xxxx
>>>fax: xxx xxxx xxxx
>>>http://www.geo.arizona.edu/
>>>http://www.ispe.arizona.edu/
>>
>>
>>--
>>Professor Keith Briffa,
>>Climatic Research Unit
>>University of East Anglia
>>Norwich, NR4 7TJ, U.K.
>>
>>Phone: xxx xxxx xxxx
>>Fax: xxx xxxx xxxx
>>
>>http://www.cru.uea.ac.uk/cru/people/briffa/
--
Jonathan T. Overpeck
Director, Institute for the Study of Planet Earth
Professor, Department of Geosciences
Professor, Department of Atmospheric Sciences
Mail and Fedex Address:
Institute for the Study of Planet Earth
715 N. Park Ave. 2nd Floor
University of Arizona
Tucson, AZ 85721
direct tel: xxx xxxx xxxx
fax: xxx xxxx xxxx
http://www.geo.arizona.edu/
http://www.ispe.arizona.edu/
</x-flowed>
Original Filename: 1121893120.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Tim Osborn <t.osborn@xxxxxxxxx.xxx>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Tom Wigley <wigley@xxxxxxxxx.xxx>
Subject: Re: crowley
Date: Wed Jul 20 16:58:xxx xxxx xxxx
Cc: p.jones@xxxxxxxxx.xxx
Hi Tom,
as a followup to Keith's email, it might be quite likely that one of the series you plot is
replaced by the instrumental record after 1960, because the file from Crowley and Lowery
that is available at the WDC-Paleoclimate contains such a record. The header states:
----------------------------------------
Crowley and Lowery 2000 (Ambio 29, 51)
Northern Hemisphere Temperature Reconstruction
Modified as published in Crowley 2000
(Science v289 p.270, 14 July 2000)
Data from Fig. 1, Crowley 2000:
Decadally smoothed time series of Crowley-Lowery reconstruction
spliced into smoothed Jones et al instrumental record after 1860
(labeled CL2.Jns11), and a slight modification (labeled CL2)
of the original Crowley and Lowery reconstruction to 1965.
----------------------------------------
The URL of this file is:
[1]ftp://ftp.ncdc.noaa.gov/pub/data/paleo/gcmoutput/crowley2000/crowley_lowery2000_nht.txt
and it is listed here:
[2]http://www.ncdc.noaa.gov/paleo/recons.html
Cheers
Tim
At 12:22 18/07/2005, Keith Briffa wrote:
as a first quick response - the Crowley numbers came from his paper with Lowery. I seem
to remember that there were 2 versions of the composite that he produced - certainly we
used the data that did not include Sargasso and Michigan site data. I presume the other
(from the CRU web site) were the data used by Phil and Mike Mann that they got from him
(where exactly did you pick then up from?)and could be the other data set (with those
sites included). It seems odd that the values are so high in the recent period of this
series and could conceivably be instrumental data , but would have to check. The scaling
of the data we used to produce the Crowley curve that formed one of the lines in our
spaghetti diagram (that we put on the web site under my name and made available to
NGDC), was based on taking the unscaled composite he sent and re-calibrating against
April - Sept. average for land North of 20 degrees Lat., and repeating his somewhat
bazaar calibration procedure (which deliberately omitted the data between 1xxx xxxx xxxxthat
did not fit with the instrumental data (remember his data are also decadal smoothed
values). In fact , as we were using summer data we calibrated over 1xxx xxxx xxxx(avoiding
the high early decades that I still believe are biased in summer) and 1xxx xxxx xxxx,
whereas he used 1xxx xxxx xxxxand 1xxx xxxx xxxx. Of the precise details might differ - but the
crux of the matter is that I suspect one of the Figures you show may have instrumental
data in the recent period - but not ours. If you say exactly where these series came
from I can ask Tim (who will have done the calibrations) to check.
As for the second question , the QR data are averaged ring widths from relatively few
site chronologies in the high north (mostly N.Eurasia - Scandinavia,Yamal,Taimyr),
though with a few other site data added in as stated. The 2001 data are the MXD data
from near 400 sites and provide the best interannual to multidecadal indication of
summer temps for land areas north of 20 degrees than any of the true proxy (ie not
including instrumental ) data. No idea what the correlation over the common 600 year
period is - but I have never said that the ring width is anything other than summer
temps for the area it covers .
Keith
At 20:38 15/07/2005, you wrote:
Keith,
Look at the attached. Can you explain to me why these plots
differ -- particularly after 1880?
Could you also explain why the Briffa data in QR 2000 are so poorly
correlated with the Briffa 2001 data?
I think I know the answers, but I want an independent and spontaneous
answer from you.
Thanks,
Tom.
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
[3]http://www.cru.uea.ac.uk/cru/people/briffa/
References
1. ftp://ftp.ncdc.noaa.gov/pub/data/paleo/gcmoutput/crowley2000/crowley_lowery2000_nht.txt
2. http://www.ncdc.noaa.gov/paleo/recons.html
3. http://www.cru.uea.ac.uk/cru/people/briffa/
Original Filename: 1121950297.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>, "Jonathan Overpeck" <jto@u.arizona.edu>
Subject: Re: the regional section and MWP Figure
Date: Thu Jul 21 08:51:xxx xxxx xxxx
Cc: <drdendro@xxxxxxxxx.xxx>, <eystein.jansen@xxxxxxxxx.xxx>
Hi Ricardo and all
this all seems fine with me - the question of the temperature observations is a moot one -
but some included seems a good idea - 1 South American and 1 New Zealand is fine - length
not as important as proximity to the records shown (but need to see what they l;look like).
will wait on other numbers - Henry is best qualified to cite most appropriate SH borehole
data and could supply a line of text . Ricardo can you ask him for these?
best wishes
Keith
At 13:52 20/07/2005, Ricardo Villalba wrote:
Hi Keith, Ed, Peck, Eystein
Regarding Peck's suggestions,
1) should we include instrumental data? If not, it could lessen the impact.
Rio de Janeiro, starting in 1851, is the longest, homogeneous temperature
record from the Southern Hemisphere. In New Zealand and Australia,
temperature records start at the same time. We do not have any long record
for the 18th century, even the first half of the 19th century. The
hemispheric record from the Southern Hemisphere will be discussed in Chapter
2 and we do not have any additional information to provide.
2) we need to include the two borehole (see previous email from me and Ed)
Definitely!! I do not have the records here in Mendoza. Keith, do you have
access to these data? As soon as I receive the borehole records I will
incorporate them in the figures. I would appreciate receiving the key
references to properly cite the records.
3) we would like to ask Keith and Tim (pretty
please...) to draft the final figure so that it
matches the other in the section and MWP box. Is
this ok, and do you have the data to do the job.
If not, we trust your kind colleagues can send
upon request?
At the time the figure is ready, I will send all the data to Keith and Tim
to draft the final figure, and the final text to incorporate in the FOD.
Cheers,
Ricardo
----- Original Message -----
From: "Jonathan Overpeck" <jto@u.arizona.edu>
To: "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>
Cc: "Keith Briffa" <k.briffa@xxxxxxxxx.xxx>; <drdendro@xxxxxxxxx.xxx>;
"Eystein Jansen" <eystein.jansen@xxxxxxxxx.xxx>
Sent: Tuesday, July 19, 2005 5:55 PM
Subject: Re: the regional section and MWP Figure
Hi SH gang - Thanks for keeping things moving
Ricardo. Eystein and I just discussed this fig on
the phone and would like to suggest the following:
1) should we include instrumental data? If not, it could lessen the impact.
2) we need to include the two borehole (see previous email from me and Ed)
3) we would like to ask Keith and Tim (pretty
please...) to draft the final figure so that it
matches the other in the section and MWP box. Is
this ok, and do you have the data to do the job.
If not, we trust your kind colleagues can send
upon request?
Many thanks, Peck and Eystein
>Dear Keith and Ed,
>
>Please, find attached the new version of the SH figure for the IPCC. I
have
>now included the New Zealand record. All the records have been scaled to 4
>
Original Filename: 1121950401.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: Tim Osborn <t.osborn@xxxxxxxxx.xxx>
Subject: Fwd: Re: CLA feedback on Tom and the MWP
Date: Thu Jul 21 08:53:xxx xxxx xxxx
Date: Wed, 20 Jul 2005 09:53:xxx xxxx xxxx
From: Tom Crowley <tcrowley@xxxxxxxxx.xxx>
User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.4)
Gecko/20030624 Netscape/7.1
X-Accept-Language: en-us, en
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
CC: Jonathan Overpeck <jto@u.arizona.edu>,
Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, t.osborn@xxxxxxxxx.xxx
Subject: Re: CLA feedback on Tom and the MWP
X-UEA-Spam-Score: 0.0
X-UEA-Spam-Level: /
X-UEA-Spam-Flag: NO
Keith, if you can find more I see no problem - it seems that a lot of the data you used
was via Cook and colleagues - I was unable to locate a full length record from Quebec in
that time series, but maybe you are relying on something else - if so can I have it!?
other suggestions: provide a more general label to sites - eg, mangazeyek (sp)/yamal
could be listed as polar urals - taimyr central Siberia.
China shoudl be relabeled as east Asia as it does include some information from Japan
and the Tibetan Plateau (L. Thompson) and we don't want to get into some political to-do
by calling Tibet "Chinese".
that's all I can think of for present, good sailing, tom
Keith Briffa wrote:
Hi all
think this is resolved now (virtually) -
We use series that total to Tom/Gabi composite , and we can cite this as an example of
the scatter of regional records "in a typical reconstruction". This avoids very
difficult issue of what is the best way to aggregate certain data sets - we are simply
illustrating the point with one published (by then) data set.
The issue of the composite is then not an issue either , because it is not a new
(unpublished) composite that we were concerned about - though I still believe it is a
distraction to put the composite in. It would be best to use data from 800 or 850 at
least , and go to 1500 (?) and presumably normalise over the whole period of data shown.
OK? Even though you guys all wish to go with the reduced period (ie not up the present)
, but my own instinct is that this might later come back to haunt us - but will take
your lead.
I agree the look of the Figure should match the others.
So, if Tom will send the data sets (his regional curves) , Tim will plot and send back
asap for scrutiny. Thanks Tom and thanks for your help with this - further comments on
latest version of 6.5 (last 2000 years) still welcome , though will be incorporating a
few changes in response to David and Fortunat input , and SH bit (from Ricardo and Ed)
still to go in and regional section to be revised (after input from Peck et al.)
cheers
Keith
.
At 21:42 19/07/2005, Jonathan Overpeck wrote:
Hi Keith and Tim: Just got off the phone with Eystein, and hopefully he will sleep ok
knowing that we have a plan for the MWP fig and Tom...
Please ask questions if we don't cover all the key points, but here's what we think:
1) the MWP fig should span the MWP only, and should emphasize variation in regional
amplitude (we agree that we must be clear that this fig is not a reconstruction) - that
is, it is best to use time series representing regions, assuming that the regional
series do represent a region ok with one or more input series. We want to avoid a
regional bias if we can - this is what got us into all the MWP misunderstanding in the
first place, perhaps (e.g., nice MWP in Europe/Atlantic region - must be global)
2) If you guys could agree on the series and the interval, that'd be great. We agree it
would be good to start before 1000 and end before the Renaissance (15th century?). If
you want more feedback on these issues, we're happy to provide, but it seems logical
that you pick series and intervals so that each series covers the entire interval
selected.
3) Don't use the Chesapeak record - it is likely biased by salinity
4) We'd like Keith and Tim to draft the final figure so that it matches the look and
style of the other two figs they have made. Hope this is doable. Tom, does Keith have
all the data? Thanks for sending if not.
5) We agree that Tom should NOT be a CA given that he was officially one of the ZOD
reviewers. Of course, this doesn't represent a real conflict, but we need to avoid even
the appearance of conflict. We greatly appreciate all the feedback that Tom is
providing! Is this plan ok w/ you Tom? We think you're cool with it, but just want to
check one more time.
That... it is. Please let us know if there are any more questions. Keith - feel free to
try and get Eystein on his cell doing your work hours if you want quick feedback. Or we
can do this by email - he's not in a very email friendly place right now, but the
fishing appears to be ok.
Again, thanks to you both for all the discussion and thought that has gone into this
figure.
Best, peck
--
Jonathan T. Overpeck
Director, Institute for the Study of Planet Earth
Professor, Department of Geosciences
Professor, Department of Atmospheric Sciences
Mail and Fedex Address:
Institute for the Study of Planet Earth
715 N. Park Ave. 2nd Floor
University of Arizona
Tucson, AZ 85721
direct tel: xxx xxxx xxxx
fax: xxx xxxx xxxx
[1]http://www.geo.arizona.edu/
[2]http://www.ispe.arizona.edu/
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
[3]http://www.cru.uea.ac.uk/cru/people/briffa/
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: xxx xxxx xxxx
Fax: xxx xxxx xxxx
[4]http://www.cru.uea.ac.uk/cru/people/briffa/
References
1. http://www.geo.arizona.edu/
2. http://www.ispe.arizona.edu/
3. http://www.cru.uea.ac.uk/cru/people/briffa/
4. http://www.cru.uea.ac.uk/cru/people/briffa/
Original Filename: 1121964854.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Tom Crowley <tcrowley@xxxxxxxxx.xxx>
To: Tim Osborn <t.osborn@xxxxxxxxx.xxx>
Subject: Re: MWP figure
Date: Thu, 21 Jul 2005 12:54:xxx xxxx xxxx
Cc: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Jonathan Overpeck <jto@u.arizona.edu>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
<x-flowed>
Tim, we are getting close but there are a few items to discuss:
1) seven of the eight time series are from the Hegerl et al paper, now
out for review in Nature
2) the eighth time series is from Brian Luckmans recent extension of the
Alberta record to the 10th century - we used his original time series in
the H et al paper because the comparisons between model and observations
had been going on for a while, in fact before the new Luckman paper came
out, and we did not want to switch horses in midstream by changing the
composite - as you know the Luckman paper is either accepted or
published in CD, so there is no problem changing that
3) although technically the time series are not the same they are very
close, if you want me to do some comparisons I can, but I could not get
to it until probably tuesday of next week - I don't particularly see any
problem in makng such an addition
4) we cannot extend the time series back to 800 without dropping out
something - the reason we start at 945 is that is the first year when
all the records are available - if we go back to 800 we do so at the
cost of dropping 2 or possibly even 3 records. as our Dark Ages
reconstruction starting at 560 indicates (att.), the biggest warming
between xxx xxxx xxxxis in the late 10the century (xxx xxxx xxxx), we did not
think we missing out on anything by starting at 945 rather than 800.
I await your feedback on this increasingly intricate issue, tom
Tim Osborn wrote:
> Hi Tom,
>
> In Keith's email below, when he says "we use series that total to
> Tom/Gabi composite", he doesn't mean that *our* mock up of the figure
> uses these series, but that if the series shown in *your* draft figure
> are the same as those used in the Hegerl/Crowley recon that is
> currently submitted ("...a twice validated climate record...") then we
> will go with *your* figure. It is fine then to include the "composite
> series" and the instrumental data and a temperature scale. Our
> previous concerns about these latter points were that it might be seen
> as another new NH temperature reconstruction. But if in fact the
> composite and its expression as a temperature are not a new NH T
> recon, but are in fact identical to the published (submitted, at
> least) Hegerl/Crowley NH T recon (which is already included in the
> main intercomparison figure) then there's no problem.
>
> Does your figure equate to the new Hegerl/Crowley NH T recon? If so,
> we should go with your MWP figure, though the CLAs want me to draw it
> in the same style as the others and also cut the time period down to a
> few centuries spanning the MWP. Keith suggests beginning in 800 or 850.
>
> Would it be possible therefore to send the data series you used for
> your figure, but beginning in 800/850, so I can plot the figure in the
> required form?
>
> Cheers
>
> Tim
>
> At 14:53 20/07/2005, Tom Crowley wrote:
>
>> Keith, if you can find more I see no problem - it seems that a lot of
>> the data you used was via Cook and colleagues - I was unable to
>> locate a full length record from Quebec in that time series, but
>> maybe you are relying on something else - if so can I have it!?
>>
>> other suggestions: provide a more general label to sites - eg,
>> mangazeyek (sp)/yamal could be listed as polar urals - taimyr
>> central Siberia.
>>
>> China shoudl be relabeled as east Asia as it does include some
>> information from Japan and the Tibetan Plateau (L. Thompson) and we
>> don't want to get into some political to-do by calling Tibet "Chinese".
>>
>> that's all I can think of for present, good sailing, tom
>>
>> Keith Briffa wrote:
>>
>>> Hi all
>>> think this is resolved now (virtually) -
>>>
>>> We use series that total to Tom/Gabi composite , and we can cite
>>> this as an example of the scatter of regional records "in a typical
>>> reconstruction". This avoids very difficult issue of what is the
>>> best way to aggregate certain data sets - we are simply illustrating
>>> the point with one published (by then) data set.
>>> The issue of the composite is then not an issue either , because it
>>> is not a new (unpublished) composite that we were concerned about -
>>> though I still believe it is a distraction to put the composite in.
>>> It would be best to use data from 800 or 850 at least , and go to
>>> 1500 (?) and presumably normalise over the whole period of data
>>> shown. OK? Even though you guys all wish to go with the reduced
>>> period (ie not up the present) , but my own instinct is that this
>>> might later come back to haunt us - but will take your lead.
>>> I agree the look of the Figure should match the others.
>>> So, if Tom will send the data sets (his regional curves) , Tim will
>>> plot and send back asap for scrutiny. Thanks Tom and thanks for
>>> your help with this - further comments on latest version of 6.5
>>> (last 2000 years) still welcome , though will be incorporating a few
>>> changes in response to David and Fortunat input , and SH bit (from
>>> Ricardo and Ed) still to go in and regional section to be revised
>>> (after input from Peck et al.)
>>> cheers
>>> Keith
>>> .
>>>
>>>
>>> At 21:42 19/07/2005, Jonathan Overpeck wrote:
>>>
>>>> Hi Keith and Tim: Just got off the phone with Eystein, and
>>>> hopefully he will sleep ok knowing that we have a plan for the MWP
>>>> fig and Tom...
>>>>
>>>> Please ask questions if we don't cover all the key points, but
>>>> here's what we think:
>>>>
>>>> 1) the MWP fig should span the MWP only, and should emphasize
>>>> variation in regional amplitude (we agree that we must be clear
>>>> that this fig is not a reconstruction) - that is, it is best to use
>>>> time series representing regions, assuming that the regional series
>>>> do represent a region ok with one or more input series. We want to
>>>> avoid a regional bias if we can - this is what got us into all the
>>>> MWP misunderstanding in the first place, perhaps (e.g., nice MWP in
>>>> Europe/Atlantic region - must be global)
>>>>
>>>> 2) If you guys could agree on the series and the interval, that'd
>>>> be great. We agree it would be good to start before 1000 and end
>>>> before the Renaissance (15th century?). If you want more feedback
>>>> on these issues, we're happy to provide, but it seems logical that
>>>> you pick series and intervals so that each series covers the entire
>>>> interval selected.
>>>>
>>>> 3) Don't use the Chesapeak record - it is likely biased by salinity
>>>>
>>>> 4) We'd like Keith and Tim to draft the final figure so that it
>>>> matches the look and style of the other two figs they have made.
>>>> Hope this is doable. Tom, does Keith have all the data? Thanks for
>>>> sending if not.
>>>>
>>>> 5) We agree that Tom should NOT be a CA given that he was
>>>> officially one of the ZOD reviewers. Of course, this doesn't
>>>> represent a real conflict, but we need to avoid even the appearance
>>>> of conflict. We greatly appreciate all the feedback that Tom is
>>>> providing! Is this plan ok w/ you Tom? We think you're cool with
>>>> it, but just want to check one more time.
>>>>
>>>> That... it is. Please let us know if there are any more questions.
>>>> Keith - feel free to try and get Eystein on his cell doing your
>>>> work hours if you want quick feedback. Or we can do this by email -
>>>> he's not in a very email friendly place right now, but the fishing
>>>> appears to be ok.
>>>>
>>>> Again, thanks to you both for all the discussion and thought that
>>>> has gone into this figure.
>>>>
>>>> Best, peck
>>>> --
>>>> Jonathan T. Overpeck
>>>> Director, Institute for the Study of Planet Earth
>>>> Professor, Department of Geosciences
>>>> Professor, Department of Atmospheric Sciences
>>>>
>>>> Mail and Fedex Address:
>>>>
>>>> Institute for the Study of Planet Earth
>>>> 715 N. Park Ave. 2nd Floor
>>>> University of Arizona
>>>> Tucson, AZ 85721
>>>> direct tel: xxx xxxx xxxx
>>>> fax: xxx xxxx xxxx
>>>> http://www.geo.arizona.edu/
>>>> http://www.ispe.arizona.edu/
>>>
>>>
>>>
>>> --
>>> Professor Keith Briffa,
>>> Climatic Research Unit
>>> University of East Anglia
>>> Norwich, NR4 7TJ, U.K.
>>>
>>> Phone: xxx xxxx xxxx
>>> Fax: xxx xxxx xxxx
>>>
>>> http://www.cru.uea.ac.uk/cru/people/briffa/
>>
>>
>
> Dr Timothy J Osborn
> Climatic Research Unit
> School of Environmental Sciences, University of East Anglia
> Norwich NR4 7TJ, UK
>
> e-mail: t.osborn@xxxxxxxxx.xxx
> phone: xxx xxxx xxxx
> fax: xxx xxxx xxxx
> web: http://www.cru.uea.ac.uk/~timo/
> sunclock: http://www.cru.uea.ac.uk/~timo/sunclock.htm
>
</x-flowed>
Attachment Converted: "c:eudoraattachCH.DA.jpg"
Original Filename: 1121974981.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
To: "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>
Subject: Re: the regional section and MWP Figure
Date: Thu Jul 21 15:43:xxx xxxx xxxx
Cc: "Jonathan Overpeck" <jto@u.arizona.edu>, <drdendro@xxxxxxxxx.xxx>, <eystein.jansen@xxxxxxxxx.xxx>, "Tim Osborn" <t.osborn@xxxxxxxxx.xxx>
Ricardo
Tim is contacting Henry now - so forget Boreholes for time being
cheers
Keith
At 15:23 21/07/2005, Ricardo Villalba wrote:
Hi Keith and all,
Following Peck's advise I will include for each reconstruction the observed
record. Obviously, I have the Patagonian instrumental records, but I need
from Ed the Tasmania and Hokitika (New Zealand) observed records.
Sorry for my ignorance on borehole, but I am not familiar with Henry's work.
If you send me his e-mail, I could ask him for the data and a line of text
on borehole from the SH. Cheers,
Ricardo
----- Original Message -----
From: "Keith Briffa" <k.briffa@xxxxxxxxx.xxx>
To: "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>; "Jonathan Overpeck"
<jto@u.arizona.edu>
Cc: <drdendro@xxxxxxxxx.xxx>; <eystein.jansen@xxxxxxxxx.xxx>
Sent: Thursday, July 21, 2005 4:51 AM
Subject: Re: the regional section and MWP Figure
Hi Ricardo and all
this all seems fine with me - the question of the temperature observations
is a moot one - but some included seems a good idea - 1 South American and
1 New Zealand is fine - length not as important as proximity to the
records shown (but need to see what they l;look like).
will wait on other numbers - Henry is best qualified to cite most
appropriate SH borehole data and could supply a line of text . Ricardo can
you ask him for these?
best wishes
Keith
At 13:52 20/07/2005, Ricardo Villalba wrote:
>Hi Keith, Ed, Peck, Eystein
>
>
>
>Regarding Peck's suggestions,
>
>
>1) should we include instrumental data? If not, it could lessen the impact.
>
>
>
>Rio de Janeiro, starting in 1851, is the longest, homogeneous temperature
>record from the Southern Hemisphere. In New Zealand and Australia,
>temperature records start at the same time. We do not have any long record
>for the 18th century, even the first half of the 19th century. The
>hemispheric record from the Southern Hemisphere will be discussed in
Chapter
>2 and we do not have any additional information to provide.
>
>
>2) we need to include the two borehole (see previous email from me and Ed)
>
>
>
>Definitely!! I do not have the records here in Mendoza. Keith, do you have
>access to these data? As soon as I receive the borehole records I will
>incorporate them in the figures. I would appreciate receiving the key
>references to properly cite the records.
>
>
>3) we would like to ask Keith and Tim (pretty
>please...) to draft the final figure so that it
>matches the other in the section and MWP box. Is
>this ok, and do you have the data to do the job.
>If not, we trust your kind colleagues can send
>upon request?
>
>
>
>At the time the figure is ready, I will send all the data to Keith and Tim
>to draft the final figure, and the final text to incorporate in the FOD.
>Cheers,
>
>Ricardo
>
>
>
>----- Original Message -----
>From: "Jonathan Overpeck" <jto@u.arizona.edu>
>To: "Ricardo Villalba" <ricardo@xxxxxxxxx.xxx>
>Cc: "Keith Briffa" <k.briffa@xxxxxxxxx.xxx>; <drdendro@xxxxxxxxx.xxx>;
>"Eystein Jansen" <eystein.jansen@xxxxxxxxx.xxx>
>Sent: Tuesday, July 19, 2005 5:55 PM
>Subject: Re: the regional section and MWP Figure
>
>
>Hi SH gang - Thanks for keeping things moving
>Ricardo. Eystein and I just discussed this fig on
>the phone and would like to suggest the following:
>
>1) should we include instrumental data? If not, it could lessen the impact.
>2) we need to include the two borehole (see previous email from me and Ed)
>3) we would like to ask Keith and Tim (pretty
>please...) to draft the final figure so that it
>matches the other in the section and MWP box. Is
>this ok, and do you have the data to do the job.
>If not, we trust your kind colleagues can send
>upon request?
>
>Many thanks, Peck and Eystein
>
> >Dear Keith and Ed,
> >
> >Please, find attached the new version of the SH figure for the IPCC. I
>have
> >now included the New Zealand record. All the records have been scaled to
4
> >
Original Filename: 1121976478.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Tim Osborn <t.osborn@xxxxxxxxx.xxx>
To: Tom Crowley <tcrowley@xxxxxxxxx.xxx>,Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: MWP figure
Date: Thu, 21 Jul 2005 16:07:58 +0100
Cc: Jonathan Overpeck <jto@u.arizona.edu>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
<x-flowed>
Hi Tom,
In Keith's email below, when he says "we use series that total to Tom/Gabi
composite", he doesn't mean that *our* mock up of the figure uses these
series, but that if the series shown in *your* draft figure are the same as
those used in the Hegerl/Crowley recon that is currently submitted ("...a
twice validated climate record...") then we will go with *your* figure. It
is fine then to include the "composite series" and the instrumental data
and a temperature scale. Our previous concerns about these latter points
were that it might be seen as another new NH temperature
reconstruction. But if in fact the composite and its expression as a
temperature are not a new NH T recon, but are in fact identical to the
published (submitted, at least) Hegerl/Crowley NH T recon (which is already
included in the main intercomparison figure) then there's no problem.
Does your figure equate to the new Hegerl/Crowley NH T recon? If so, we
should go with your MWP figure, though the CLAs want me to draw it in the
same style as the others and also cut the time period down to a few
centuries spanning the MWP. Keith suggests beginning in 800 or 850.
Would it be possible therefore to send the data series you used for your
figure, but beginning in 800/850, so I can plot the figure in the required
form?
Cheers
Tim
At 14:53 20/07/2005, Tom Crowley wrote:
>Keith, if you can find more I see no problem - it seems that a lot of the
>data you used was via Cook and colleagues - I was unable to locate a full
>length record from Quebec in that time series, but maybe you are relying
>on something else - if so can I have it!?
>
>other suggestions: provide a more general label to sites - eg, mangazeyek
>(sp)/yamal could be listed as polar urals - taimyr central Siberia.
>
>China shoudl be relabeled as east Asia as it does include some information
>from Japan and the Tibetan Plateau (L. Thompson) and we don't want to get
>into some political to-do by calling Tibet "Chinese".
>
>that's all I can think of for present, good sailing, tom
>
>Keith Briffa wrote:
>
>>Hi all
>>think this is resolved now (virtually) -
>>
>>We use series that total to Tom/Gabi composite , and we can cite this as
>>an example of the scatter of regional records "in a typical
>>reconstruction". This avoids very difficult issue of what is the best way
>>to aggregate certain data sets - we are simply illustrating the point
>>with one published (by then) data set.
>>The issue of the composite is then not an issue either , because it is
>>not a new (unpublished) composite that we were concerned about - though I
>>still believe it is a distraction to put the composite in. It would be
>>best to use data from 800 or 850 at least , and go to 1500 (?) and
>>presumably normalise over the whole period of data shown. OK? Even though
>>you guys all wish to go with the reduced period (ie not up the present) ,
>>but my own instinct is that this might later come back to haunt us - but
>>will take your lead.
>>I agree the look of the Figure should match the others.
>>So, if Tom will send the data sets (his regional curves) , Tim will plot
>>and send back asap for scrutiny. Thanks Tom and thanks for your help
>>with this - further comments on latest version of 6.5 (last 2000 years)
>>still welcome , though will be incorporating a few changes in response to
>>David and Fortunat input , and SH bit (from Ricardo and Ed) still to go
>>in and regional section to be revised (after input from Peck et al.)
>>cheers
>>Keith
>>.
>>
>>
>> At 21:42 19/07/2005, Jonathan Overpeck wrote:
>>
>>>Hi Keith and Tim: Just got off the phone with Eystein, and hopefully he
>>>will sleep ok knowing that we have a plan for the MWP fig and Tom...
>>>
>>>Please ask questions if we don't cover all the key points, but here's
>>>what we think:
>>>
>>>1) the MWP fig should span the MWP only, and should emphasize variation
>>>in regional amplitude (we agree that we must be clear that this fig is
>>>not a reconstruction) - that is, it is best to use time series
>>>representing regions, assuming that the regional series do represent a
>>>region ok with one or more input series. We want to avoid a regional
>>>bias if we can - this is what got us into all the MWP misunderstanding
>>>in the first place, perhaps (e.g., nice MWP in Europe/Atlantic region -
>>>must be global)
>>>
>>>2) If you guys could agree on the series and the interval, that'd be
>>>great. We agree it would be good to start before 1000 and end before the
>>>Renaissance (15th century?). If you want more feedback on these issues,
>>>we're happy to provide, but it seems logical that you pick series and
>>>intervals so that each series covers the entire interval selected.
>>>
>>>3) Don't use the Chesapeak record - it is likely biased by salinity
>>>
>>>4) We'd like Keith and Tim to draft the final figure so that it matches
>>>the look and style of the other two figs they have made. Hope this is
>>>doable. Tom, does Keith have all the data? Thanks for sending if not.
>>>
>>>5) We agree that Tom should NOT be a CA given that he was officially one
>>>of the ZOD reviewers. Of course, this doesn't represent a real conflict,
>>>but we need to avoid even the appearance of conflict. We greatly
>>>appreciate all the feedback that Tom is providing! Is this plan ok w/
>>>you Tom? We think you're cool with it, but just want to check one more time.
>>>
>>>That... it is. Please let us know if there are any more questions. Keith
>>>- feel free to try and get Eystein on his cell doing your work hours if
>>>you want quick feedback. Or we can do this by email - he's not in a very
>>>email friendly place right now, but the fishing appears to be ok.
>>>
>>>Again, thanks to you both for all the discussion and thought that has
>>>gone into this figure.
>>>
>>>Best, peck
>>>--
>>>Jonathan T. Overpeck
>>>Director, Institute for the Study of Planet Earth
>>>Professor, Department of Geosciences
>>>Professor, Department of Atmospheric Sciences
>>>
>>>Mail and Fedex Address:
>>>
>>>Institute for the Study of Planet Earth
>>>715 N. Park Ave. 2nd Floor
>>>University of Arizona
>>>Tucson, AZ 85721
>>>direct tel: xxx xxxx xxxx
>>>fax: xxx xxxx xxxx
>>>http://www.geo.arizona.edu/
>>>http://www.ispe.arizona.edu/
>>
>>
>>--
>>Professor Keith Briffa,
>>Climatic Research Unit
>>University of East Anglia
>>Norwich, NR4 7TJ, U.K.
>>
>>Phone: xxx xxxx xxxx
>>Fax: xxx xxxx xxxx
>>
>>http://www.cru.uea.ac.uk/cru/people/briffa/
>
Dr Timothy J Osborn
Climatic Research Unit
School of Environmental Sciences, University of East Anglia
Norwich NR4 7TJ, UK
e-mail: t.osborn@xxxxxxxxx.xxx
phone: xxx xxxx xxxx
fax: xxx xxxx xxxx
web: http://www.cru.uea.ac.uk/~timo/
sunclock: http://www.cru.uea.ac.uk/~timo/sunclock.htm
</x-flowed>
Original Filename: 1122052662.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: David Rind <drind@xxxxxxxxx.xxx>
To: Eystein Jansen <Eystein.Jansen@xxxxxxxxx.xxx>
Subject: Re: [wg1-ar4-ch06] Updated 6.1 (inc. Bette's comments)
Date: Fri, 22 Jul 2005 13:17:xxx xxxx xxxx
Cc: wg1-ar4-ch06@xxxxxxxxx.xxx
<x-flowed>
Hi Eyestein,
Thanks for your comments. With respect to the
suggested changes in paragraphs 1,2 and 4, they
seem fine to me. However, I think we need to
include in paragraph 5 potential reasons as to
why the substantial (and not just significant)
high latitude warming that appears in the
mid-Pliocene record is not produced in GCMs in
response to higher CO2, in general - otherwise we
leave the reader with a big question and no
possible solution. The tendency of GCM
simulations for the future climate to produce an
NADW decrease forces those simulations to have
minimal high latitude warming in the North
Atlantic, exactly opposite the inference from the
Pliocene paleo-record (which is quite robust in
this respect at least). If the Pliocene record is
indicating the opposite of what current models
are predicting, it may be offering us a valuable
clue...
The suggested reasons also include the comment
that the lack of land ice at high northern
latitudes might be a strong contributing cause -
which would make it a no-analog situation, and
hence not fully a GCM problem.
I would favor leaving those two sentences as they were.
David
At 5:19 PM +0200 7/22/05, Eystein Jansen wrote:
>Hi,
>see enclosed some comments to the last version
>of the deep time box. I propose some deletions
>and some toning down of language. What do you
>think?
>
>Eystein
>--
>______________________________________________________________
>Eystein Jansen
>Professor/Director
>Bjerknes Centre for Climate Research and
>Dep. of Earth Science, Univ. of Bergen
>All
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From: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
To: David Rind <drind@xxxxxxxxx.xxx>
Subject: Ad: Re: [wg1-ar4-ch06] Updated 6.1 (inc. Bette's comments)
Date: Sat, 23 Jul 2005 09:40:27 +0200
Reply-to: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
Cc: wg1-ar4-ch06@xxxxxxxxx.xxx
Hi David,
thanks for the reply. I think your arguments to add some comments of explanation re Pliocene warmth are convincing and that there is potential relevance for IPCC concerning lat. heat transport in a world with less land and sea ice. My concern is that I don't think the text should be interpreted to imply that the Mid Pliocene was free of Arctic sea ice and Greenland was ice free. There is evidence from the recent IODP Central Arctic Drilling (have to check what ref. to use) of sea ice cover through the Pliocene. I have publishet on IRD evidence for a Greenland ice sheet of some sort. Concerning THC, N Atlantic data indicate strong presence of NADW akin to now, but we cannot constrain overturning rate. Both Nordic Seas an Arctic Ocean was poorly ventilated and deep water formation to feed overflows was shallover, perhaps due to higher temperature?
Instead of deleting the section I proposed, I suggest changing it as follows: After (Rind and Chadler 1991) add , "for which available proxy data are inconclusive", and
Instead of writing "absence of land ice", write " reduced extent of land and sea ice". I will find the best refs for this on Monday.
Cheers
Eystein
_______________________________________________
Wg1-ar4-ch06 mailing list
Wg1-ar4-ch06@xxxxxxxxx.xxx
http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
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From: Tom Crowley <tcrowley@xxxxxxxxx.xxx>
To: Jonathan Overpeck <jto@u.arizona.edu>
Subject: participation in IPCC
Date: Mon, 25 Jul 2005 10:16:xxx xxxx xxxx
Cc: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
<x-flowed>
Hi all, there is another reason why I should not be formally listed as
an LA - it is my understanding that IPCC contributors have to be a
little careful about getting involved in political matters that could be
used to impugn the integrity of the process - well I am starting to do
just that, with the attached commen in Eos, plus some radio interviews
where I have been somewhat pointed in my thoughts.
I suppose its still ok to be a reviewer, but even then you might keep
these comments in mind, tom
>
</x-flowed>
Attachment Converted: "c:eudoraattachCrowley1.EOS.2005.pdf"
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From: Stefan Rahmstorf <rahmstorf@xxxxxxxxx.xxx>
To: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Subject: Last Millennium section 6.5 - comments by SR
Date: Tue, 26 Jul 2005 12:09:33 +0200
Cc: wg1-ar4-ch06@xxxxxxxxx.xxx, Jonathan Overpeck <jto@u.arizona.edu>, Eystein Jansen <Eystein.Jansen@xxxxxxxxx.xxx>
Hi Keith and all, (please everyone have a look at point (4))
I think section 6.5 is in remarkably good shape (certainly compared to my own..).
There are some comments from me:
(1) About the new proxy reconstructions, the section says: "Most of these are shown..." in
the Figure. This immediately raises the question: why not all? Which one is not shown? This
section will be scrutinised with great suspicion by some people, so we need to be careful.
Can you clarify which one you left out, and why? Or can we just write: "These are shown..."
That would be much nicer.
(2) Several times you say "simply scaled" - would "scaled" do as well? The "simply" in this
context sounds a bit like we criticise that.
(3) Is "predictand" a word that everybody knows? I'd never seen it before.
(4) Now here is my biggest question, that I think we need to discuss in the whole group.
Figure 6.5.2-1 shows simulations of the past millennium, relative to 1xxx xxxx xxxxmeans. Is
this really the best reference period?
Contra: it differs from how we show the data reconstructions, i.e., relative to 1xxx xxxx xxxx.
Everyone knows what that climate actually was, since there are good instrumental data for
1xxx xxxx xxxx, so that it makes sense to look at changes relative to that period. Nobody knows
what the real 1xxx xxxx xxxxmean was, so this is a fictitious baseline.
Pro: it gets rid of "end effects", i.e. model initialisation problems at the beginning (as
in Von Storch 04), and different anthropogenic forcings used at the end (e.g. some ignore
aerosols); the simulations look closer together in this way (right?)
I have not formed a clear opinion on what is best.
(5) Also on the figures: I like the grey bands, but here's a suggestion for improvement:
instead of leaving the core region between those two bands white, I think they should also
be shaded - either the same grey, or a darker shade of grey. This makes it more clear that
we are talking about one, wide uncertainty band here, not about two seperate things. It had
me confused at first when I saw it, even though I was there when we discussed this in
Beijing.
Final point: we need to keep an eye on developments concerning the model tests of the proxy
method, there seem to be several important things in the pipeline there.
Cheers, Stefan
--
To reach me directly please use: [1]rahmstorf@xxxxxxxxx.xxx
(My former addresses @pik-potsdam.de are read by my assistant Brigitta.)
Stefan Rahmstorf
[2]www.ozean-klima.de
[3]www.realclimate.org
References
1. mailto:rahmstorf@xxxxxxxxx.xxx
2. http://www.ozean-klima.de/
3. http://www.realclimate.org/
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From: Tim Osborn <T.Osborn@xxxxxxxxx.xxx>
To: eystein.jansen@xxxxxxxxx.xxx, jto@u.arizona.edu, k.briffa@xxxxxxxxx.xxx
Subject: MWP figure
Date: Tue, 26 Jul 2005 20:00:29 +0100
Cc: t.osborn@xxxxxxxxx.xxx
Dear Keith, Peck and Eystein,
as you'll have seen from Tom C's replies to my fairly direct requests for the
data that went into his MWP
figure, he seems somehow reluctant to send it to me and prefers me to find it
myself (including
spending a week re-assembling a Mongolian composite). I have no time to do
this, so have instead
reverted to using the very similar data that we already had. I'm sure it's so
similar that it tells the same
story.
So, the attached file is my latest attempt at the MWP figure. It shows 8
local/regional proxy series,
normalised over a common period after filtering to the 20-year and longer time
scale. It also shows a
composite mean, and no temperature scale. The period covered is 850 to 1350.
What do you think? Hopefully it is what you want.
I've started on the SH figure, having received data from Ricardo and borehole
series for SH, S. Africa and
Australia from Jason/Henry. I need to sort out Tasmania / New Zealand
instrumental data - Ed has this,
though I could extract appropriate boxes from the Jone et al. gridded data set
if necessary.
I'll include these series:
S American trees*2 plus instrumental T overlaid
S African and Australian boreholes (must also overlay instrumental T to
explain why values are all
negative - due to early sampling prior to strongest warmng)
Tasmanian and New Zealand trees*2 plus instrumental T)
It may be Friday by the time I get this one done.
Cheers
Tim
Attachment Converted: "c:documents and settingstim osbornmy documentseudoraattachipccar4_mwpbox.pdf"
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From: Phil Jones <p.jones@xxxxxxxxx.xxx>
To: Kevin Trenberth <trenbert@xxxxxxxxx.xxx>
Subject: Re: New versions
Date: Thu Jul 28 09:37:xxx xxxx xxxx
Cc: Susan Solomon <ssolomon@xxxxxxxxx.xxx>
Kevin/Susan,
I'll look over 3.9. A quick look at the back references to sections which contain
the detail summarized here, suggests that you've got the right level of section. I guess
we could add a sentence to say that this/these are the principal section(s), but the whole
of the x.x section is likely also relevant.
I've added Susan in to show what we're doing. It might be appropriate for other
chapters. Part of my reason was traceability, but also we are referring to subsequent
sections in Chapters 4 and 5.
The figures seem to be coming along well. Pdfs are also. I'll send another
reminder about these out later today, when I've had one last look for a few of them.
I'll attach section numbers as there are so few now.
Cheers
Phil
The bulletted points and back references are below.
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From: Fortunat Joos <joos@xxxxxxxxx.xxx>
To: Fortunat Joos <joos@xxxxxxxxx.xxx>
Subject: Re: [Wg1-ar4-ch06] introduction 6.2.xxx xxxx xxxx.4.1 holocene solar.
Date: Thu, 28 Jul 2005 21:49:44 +0200
Cc: Eystein Jansen <Eystein.Jansen@xxxxxxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: 7bit
X-Mime-Autoconverted: from 8bit to 7bit by courier 0.47
Hi Peck and Eystein,
Here a reduced version of Box 6.2, taking into account suggestions from David
and Bette. The text is now 1.5 pages, i.e. just slightly above target. The
entire Box should now fit on less than 1 IPCC page (Assigned 0.75 page).
I am willing to take the next effort to shorten when the review comments of the
FOD are in.
With best regards,
Fortunat
Quoting Fortunat Joos <joos@xxxxxxxxx.xxx>:
> Hi Peck and Eystein,
>
> here my general comment on the introduction and specific comments on section
> 6.2.1 and 6.4.1.
>
> 6.1 and 6.2.1:
>
> Well done!
>
> (1) Perhaps, words such as 'significant' and other value judgment terms could
> be
> used somewhat less. e.g. 'With proper care, current methodologies alloww more
> accurate age models' more accurate than what? We always hope that things are
> done with proper care.
>
> (2) The following sentence must in my opinion be deleted: 'but also note that
> new work reveals that
> cosmogeninc-isotope-derived estimates of solar forcing for the Holocene are
> not
> likely as well-constrained as commonly thought.'
>
> This is a very sweeping statement that is not backed up by the chapter text.
> It
> is also a very policy sensitive statement. We are either able to firmly
> support
> that or to drop it. I suspect that the paleo community would be divided about
> this.
>
> Scott Lehmann has just shown me a plot with a really nice correlatin between
> d18O in N-pachy in the Norht-Atlatnic and sunspots over the past 400 years.
> Yes, there appears to be a link.
>
> I also doubt that some of the existing work, e.g. Fleitman etc can be
> dismissed
> so easily.
>
> section 6.4.1:
>
> (3) I also think that the Holocene text on solar needs some readjustments.
> Linking the studies suggesting solar changes and those with NADW variations
> seems a somewhat improper comparison.
>
> The present text reads:
>
> 'Based on the correlation between changes in atmospheric concentrations of
> cosmogenic isotopes (10Be or 14C) and climate proxy records, some authors
> argue
> that solar activity may be the driver for an organised centennial to
> millennial
> scale variability (e.g., (Bond et al., 2001; Fleitmann et al., 2003) (Karlen,
> 1996) (Wang et al., 2005b), whereas others point to modes of variability
> driven
> by processes within the climate system, for instance related to the deep
> ocean
> circulation (Bianchi and McCave, 1999) (Duplessy et al., 2001) (Oppo et al.,
> 2003) (Marchal et al., 2002).'
>
> I suggest to change it to something along the following line.
>
> "'Based on the correlation between changes in atmospheric concentrations of
> cosmogenic isotopes (10Be or 14C) and climate proxy records, many studies
> suggest that solar activity may be a driver for centennial to millennial
> scale
> variability (e.g., (Bond et al., 2001; Fleitmann et al., 2003) (Karlen, 1996)
> (Wang et al., 2005b). The importance of (forced or unforced) modes of
> variability within the climate system, for instance related to the deep ocean
> circulation has been pointed out (Bianchi and McCave, 1999) (Duplessy et al.,
> 2001) (Oppo et al., 2003) (Marchal et al., 2002)."
>
> With best regards,
>
> Fortunat
>
>
>
> Quoting Fortunat Joos <joos@xxxxxxxxx.xxx>:
>
> > Hi Stefan, Peck and all,
> >
> > Here an update on the abrupt event figure and the figure caption. There
> were
> > some lost lines in the one send yesterday - please delete. I have now also
> > numbered some of the D/O events and the A1 to A4 events.
> >
> > The purpose of the figure is to demonstrate the asynchrounous evolution of
> NH
> > and SH temperatuere and the magnitude of the GHG changes during abrupt
> > events.
> >
> > Clearly, it would be great if the figure could be amended by other
> > information,
> > e.g. from the land or sediment records. We may also think about indicating
> > the
> > local Greenland temperatre change for the bigger events.
> >
> > Any ideas, suggestions, comments are welcomed.
> >
> > Peck: please include ERIC MONNIN as a Contributing author.
> >
> > Eric has synchronized the Taylor Dome and Dome C data on the GRIP time
> scale
> > and
> > helped me greatly to put toghether the records for the abrupt event and for
> > the
> > LGM-box figures.
> >
> > With best regards,
> >
> > Fortunat
> >
> > Quoting Fortunat Joos <joos@xxxxxxxxx.xxx>:
> >
> > > Hi,
> > >
> > > Here finally the abrupt event figure plus an update of the LGM-box
> figure.
> > > Will provide figure caption, section 6.6. text and shortened LGM-box
> > > tomorrow.
> > >
> > > With best regards,
> > >
> > > Fortunat
> > >
> > > --
> > > e-mail: joos@xxxxxxxxx.xxx;
> > >
> > > Until November 23
> > > National Centre for Atmospheric Research, Terrestrial Sciences, CGD
> > > 1850 Table Mesa Drive, Boulder, CO, 80305
> > > xxx xxxx xxxx(office)
> > >
> > > home address:
> > > 3655 Emerson Avenue, Boulder, CO, 80305
> > > xxx xxxx xxxx(home)
> > >
> > > After November 24
> > > Climate and Environmental Physics
> > > Sidlerstr. 5, CH-3012 Bern
> > > Phone: ++41(0xxx xxxx xxxx Fax: ++41(0xxx xxxx xxxx
> > > Internet: http://www.climate.unibe.ch/~joos/
> > >
> > >
> >
> >
> > --
> > e-mail: joos@xxxxxxxxx.xxx;
> >
> > Until November 23
> > National Centre for Atmospheric Research, Terrestrial Sciences, CGD
> > 1850 Table Mesa Drive, Boulder, CO, 80305
> > xxx xxxx xxxx(office)
> >
> > home address:
> > 3655 Emerson Avenue, Boulder, CO, 80305
> > xxx xxxx xxxx(home)
> >
> > After November 24
> > Climate and Environmental Physics
> > Sidlerstr. 5, CH-3012 Bern
> > Phone: ++41(0xxx xxxx xxxx Fax: ++41(0xxx xxxx xxxx
> > Internet: http://www.climate.unibe.ch/~joos/
> >
> >
>
>
> --
> e-mail: joos@xxxxxxxxx.xxx;
>
> Until November 23
> National Centre for Atmospheric Research, Terrestrial Sciences, CGD
> 1850 Table Mesa Drive, Boulder, CO, 80305
> xxx xxxx xxxx(office)
>
> home address:
> 3655 Emerson Avenue, Boulder, CO, 80305
> xxx xxxx xxxx(home)
>
> After November 24
> Climate and Environmental Physics
> Sidlerstr. 5, CH-3012 Bern
> Phone: ++41(0xxx xxxx xxxx Fax: ++41(0xxx xxxx xxxx
> Internet: http://www.climate.unibe.ch/~joos/
>
> _______________________________________________
> Wg1-ar4-ch06 mailing list
> Wg1-ar4-ch06@xxxxxxxxx.xxx
> http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
>
--
e-mail: joos@xxxxxxxxx.xxx;
Until November 23
National Centre for Atmospheric Research, Terrestrial Sciences, CGD
1850 Table Mesa Drive, Boulder, CO, 80305
xxx xxxx xxxx(office)
home address:
3655 Emerson Avenue, Boulder, CO, 80305
xxx xxxx xxxx(home)
After November 24
Climate and Environmental Physics
Sidlerstr. 5, CH-3012 Bern
Phone: ++41(0xxx xxxx xxxx Fax: ++41(0xxx xxxx xxxx
Internet: http://www.climate.unibe.ch/~joos/
Attachment Converted: "c:eudoraattachjoos_Ch06_FOD_LGMBox_28jul05.doc"
_______________________________________________
Wg1-ar4-ch06 mailing list
Wg1-ar4-ch06@xxxxxxxxx.xxx
http://www.joss.ucar.edu/mailman/listinfo/wg1-ar4-ch06
Original Filename: 1122669035.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Phil Jones <p.jones@xxxxxxxxx.xxx>
To: Tim Osborn <t.osborn@xxxxxxxxx.xxx>, "Tett, Simon" <simon.tett@xxxxxxxxx.xxx>
Subject: Re: Bristlecones!
Date: Fri Jul 29 16:30:xxx xxxx xxxx
Cc: Keith Briffa <k.briffa@xxxxxxxxx.xxx>
Simon,
If you go to this web page
[1]http://www.ucar.edu/news/releases/2005/ammann.shtml
You can click on a re-evaluation of MBH, which leads to a paper submitted
to Climatic Change. This shows that MBH can be reproduced. The R-code
to do this can be accessed and eventually the data - once the paper has been
accepted.
IPCC will likely conclude that all MM arguments are wrong and have
been answered in papers that have either come out or will soon. MBH
is just one curve of many - more now than there were in 2001. MBH is
still in the spaghetti of curves, and is not an outlier. If there are outliers
it will be Esper et al. and another one.
Bristlecones are only crucial to the issue if you are MM. They misused
them, by their PCA application. This is all well-known to those in the know.
I have reviewed the CC paper by Wahl and Ammann. It reproduces all
the mistakes MM have made, so they know how and why their results
have been achieved. I can send you the paper if you want, subject
to the usual rules.
MBH have all responded to the same requests as IPCC got from the
US Senate. Their responses are all posted at [2]http://www.realclimate.org/
The skeptics have shot themselves in the foot over this one.
Cheers
Phil
At 15:17 29/07/2005, Tim Osborn wrote:
At 14:27 28/07/2005, Tett, Simon wrote:
John Houghton is being quized by bits of the US senate. One question is
"Whats the status of the review of the Mann hockey stick temperature
curve? I understand that studies by Stephen McIntyre and Ross McKitrick
suggest that it relied on the statistically insignificant bristlecone
pine. Is the IPCC taking another look at that work, which forms the
basis for much of todays climate change debate?"
My current thoughts on an answer is to say that other reconstructions
show a similar pattern (though not magnitude). However how many of the
other reconstructions use the bristlecone data? [I suspect yours does
not]
Hi Simon - I was away yesterday, so couldn't answer then. Hopefully it isn't too late
to answer today.
(1) I don't understand what they mean by describing the bristlecone pine as
"statistically insignificant".
(2) The Mann, Bradley and Hughes (MBH1999) reconstruction is only one small piece of
information in today's climate change debate.
(3) As far as I understand, then yes the MBH1999 reconstruction does give quite a lot of
weight to a few western US tree-ring series, which are mostly bristlecone pines for the
longest records.
(4) Other reconstructions show similar shape (though not magnitude) and support similar
conclusions (regarding the unprecedented nature of recent warmth/warming trend). This
is the main argument to make, as you thought. Some of these other reconstructions do
not include these bristlecones (e.g. Briffa, 2000; Crowley et al., 2003; Moberg et al.,
2005; Briffa et al., 2001). Crowely and Moberg use different Bristlecone records I
think. Other reconstructions do use the same Bristlecone pines (e.g., Mann and Jones,
2004). BUT the critical thing is that the studies either do not use these Bristlecone
pines, or if they do use them, then they give them much more similar weighting to the
other records used. I think MBH1999 is the only one that might give them a dominant
weighting.
(5) IPCC is assessing all published work that relates to these issues in preparation for
the AR4 in 2007. This includes the McIntyre and McKitrick papers as well as papers that
report results contrary to McIntyre/McKitrick, such as the paper in press by Wahl and
Amman that shows the Mann et al. results are reproducible.
cc'd for additional comments to Phil and Keith (when he's back).
Cheers
Tim
Dr Timothy J Osborn
Climatic Research Unit
School of Environmental Sciences, University of East Anglia
Norwich NR4 7TJ, UK
e-mail: t.osborn@xxxxxxxxx.xxx
phone: xxx xxxx xxxx
fax: xxx xxxx xxxx
web: [3]http://www.cru.uea.ac.uk/~timo/
sunclock: [4]http://www.cru.uea.ac.uk/~timo/sunclock.htm
Prof. Phil Jones
Climatic Research Unit Telephone +44 xxx xxxx xxxx
School of Environmental Sciences Fax +44 xxx xxxx xxxx
University of East Anglia
Norwich Email p.jones@xxxxxxxxx.xxx
NR4 7TJ
UK
----------------------------------------------------------------------------
References
1. http://www.ucar.edu/news/releases/2005/ammann.shtml
2. http://www.realclimate.org/
3. http://www.cru.uea.ac.uk/~timo/
4. http://www.cru.uea.ac.uk/~timo/sunclock.htm
Original Filename: 1123163394.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Phil Jones <p.jones@xxxxxxxxx.xxx>
To: mann@xxxxxxxxx.xxx
Subject: Re: Out in latest J. Climate
Date: Thu Aug 4 09:49:xxx xxxx xxxx
Mike,
Gabi was supposed to be there but wasn't either. I think Gabi isn't
being objective as she might because of Tom C. I recall Keith
telling me that her recent paper has been rejected, not sure if outright
or not.
Gabi sees the issue from a D&A perspective, not whether any curve
is nearer the truth, but just what the envelope of the range might be.
There is an issue coming up in IPCC. Every curve needs error
bars, and having them is all that matters. It seems irrelevant whether
they are right or how they are used. Changing timescales make this
simple use impractical.
We have a new version of HadCRUT just submitted, so soon
the'll be HadCRUT3v and CRUTEM3v. The land doesn't change much.
This has errors associated with each point, but the paper doesn't yet
discuss how to use them.
I'll attach this paper. Only just been submitted to JGR - not
in this format though. This format lays it out better.
Thanks for reminding Scott.
Cheers
Phil
At 08:48 04/08/2005, you wrote:
Hi Phil,
Thanks for the heads up. Will be prepared for this then. I thought that Gabi Hegerl was
involved with this guy? Doesn't she know better? It is disturbing that she hasn't set
them straight on this.
By the way, as you may or may not have heard, its been discovered that there is a major
error in Von Storch et al '04 that they now appear to be trying to hide (they have some
obscure article in an Italian journal where they attempt to justify the error). There
are several comments that have been or are soon to be submitted to Science about this.
As it turns out, they introduces a spurious step in their supposed implementation of the
MBH98 procedure in which they detrended the series first, gives completely wrong
results.. Caspar Ammann and Gene Wahl and David Ritson of Stanford have both
independently discovered this, because they noticed that amplitude of the calibrated
signal in VS04 scales with the signal-to-noise ratio--this was the first clue that there
was a major problem. There may be calls upon Science for them to retract their paper.
The results are completely wrong, aside from the problems w/ the GKSS simulation. You
can expect to hear more about this soon...
I'll remind Scott about the proxies. He and Zhang are in the process of screening the
proxy series for temperature signals, etc. Once they've done that, should be more
useful. I expect we'll be able to get you some stuff by late August.
I did hear about the 3 papers coming out in Science. Apparently Donald Kennedy is doing
an editorial that will discuss this in the context of the whole Barton business. That
should be interesting...There will be articles by both Gavin and Steve Sherwood on
"RealClimate" in coordination with the publication of the papers in Science Express.
This should help turn the debate around.
talk to you later,
mike
Phil Jones wrote:
Mike,
He's been working with Myles Allen. Tim went to the first meeting of this
Dutch funded project near Oxford last week.
Tim said they were doing some odd things, like correlating all the proxy series
they had with CET (yes CET)! Even the few SH proxies they have. The others
who went to the meeting were Zorita and Moberg. Zorita was still showing the
GKSS run with Moberg series, even though its forcing is too large, it doesn't
have aerosols in the 20th century and has spin up problems for the first
200 years.
Meeting wasn't that productive according to Tim. There was a belief amongst
those there that all trees you used have lost low-freq, but this isn't true as you
know.
Also, it was a good job Keith wasn't there (he didn't go as his father died the
weekend before and he's not been in CRU since) as Martin assumed that RCS
was developed by Esper (who also wasn't there). Tim put them right on this
one, but RCS isn't applicable for normal tree sites, nor useful for bristlecones.
Tim said Esper was wrong is his use of RCS, but they wouldn't accept that
as Esper wasn't there to defend himself!
Basically only Tim knew anything about proxy data especially trees. Tim
got the impression that they wanted to find that MBH is wrong. Given the
previous comment, as you weren't there they are using double standards.
So, in conclusion, act carefully. Don't jump in, but some carefully thought
through comments should be productive. Suggest they read the RevG article.
Martin isn't associated with the contrarians, but he's not in possession
of the all the facts. He isn't aware of Casper's work, nor your latest study
which you sent the other day, nor Rutherford et al.
There still seems to be a belief in these lower responding proxies. This is
something we want to work on more here, as the only way it seems to show
that these lower-freq proxies aren't that great is to use higher-freq proxies.
When you're back or sometime, can you remind Scott to send your
latest set of proxies. I'll have some time in the autumn to work on them
as the AR4 should be in by Aug 12.
Science should be publishing 3 papers on the MSU issue by the end of Aug
or early Sept. This is Mears/Wentz, Santer et al. and Sherwood et al. Latter
shows that sondes are only truly reliable when flown at night. Daytime ones
have all manner of problems with heating, just like air temps on board ships -
hence the NMAT series.
I'll forward another email for interest.
Cheers
Phil
At 03:40 04/08/2005, you wrote:
Hi Phil,
Thanks, yes I'm in China now. As you might imagine, ,things have been very busy, but
calming down a bit. Looks like Barton may be backing down...
Martin Juckes has an invited talk in my session. I invited him, because he was working
w/ Stott et al, and so I assume he was legit, and not associated with the contrarians.
But if he's associated w/ the Dutch group, he may actually be a problem. Do you have
additional information about him and what he has been up to?
Thanks,
mike
Phil Jones wrote:
Mike,
Good to hear it is out !
Hope the changeover is going OK and life is getting back to normal.
If you're not gone to China yet - you'll meet someone called Martin
Dukes (?). He's giving a talk at your session. He knows about maths
etc but not much about paleo ! Might need some education, but
is probably OK. Not met him, but Tim has. Doing some worked
funded by the Dutch govt on the hockey stick.
Cheers
Phil
At 04:05 03/08/2005, you wrote:
Dear Colleagues,
FYI, two papers attached:
First (reprint), Rutherford et al, is now out in latest issue of Journal of Climate.
This paper, aside from addressing other more scientifically-worthwhile issues, also
happens to discredit most of the McIntyre and McKitrick claims.
Second (preprint), Mann et al, is formally in press (i.e., has gone off to the AMS
production staff) in Journal of Climate. This paper strongly challenges the conclusions
of von Storch et al (2004), and raises some methodological issues w/ the approach used
by Moberg et al (2005).
Feel free to pass along to others. Thanks
Mike
--
Michael E. Mann
Associate Professor
Director, Earth System Science Center (ESSC)
Department of Meteorology Phone: (8xxx xxxx xxxx
503 Walker Building FAX: (8xxx xxxx xxxx
The Pennsylvania State University email: mann@xxxxxxxxx.xxx
University Park, PA 16xxx xxxx xxxx
[1]http://www.evsc.virginia.edu/faculty/people/mann.shtml
Prof. Phil Jones
Climatic Research Unit Telephone +44 xxx xxxx xxxx
School of Environmental Sciences Fax +44 xxx xxxx xxxx
University of East Anglia
Norwich Email p.jones@xxxxxxxxx.xxx
NR4 7TJ
UK ----------------------------------------------------------------------------
--
Michael E. Mann
Associate Professor
Director, Earth System Science Center (ESSC)
Department of Meteorology Phone: (8xxx xxxx xxxx
503 Walker Building FAX: (8xxx xxxx xxxx
The Pennsylvania State University email: mann@xxxxxxxxx.xxx
University Park, PA 16xxx xxxx xxxx
[2]http://www.evsc.virginia.edu/faculty/people/mann.shtml
Prof. Phil Jones
Climatic Research Unit Telephone +44 xxx xxxx xxxx
School of Environmental Sciences Fax +44 xxx xxxx xxxx
University of East Anglia
Norwich Email p.jones@xxxxxxxxx.xxx
NR4 7TJ
UK
----------------------------------------------------------------------------
--
Michael E. Mann
Associate Professor
Director, Earth System Science Center (ESSC)
Department of Meteorology Phone: (8xxx xxxx xxxx
503 Walker Building FAX: (8xxx xxxx xxxx
The Pennsylvania State University email: mann@xxxxxxxxx.xxx
University Park, PA 16xxx xxxx xxxx
[3]http://www.evsc.virginia.edu/faculty/people/mann.shtml
Prof. Phil Jones
Climatic Research Unit Telephone +44 xxx xxxx xxxx
School of Environmental Sciences Fax +44 xxx xxxx xxxx
University of East Anglia
Norwich Email p.jones@xxxxxxxxx.xxx
NR4 7TJ
UK
----------------------------------------------------------------------------
References
1. http://www.evsc.virginia.edu/faculty/people/mann.shtml
2. http://www.evsc.virginia.edu/faculty/people/mann.shtml
3. http://www.evsc.virginia.edu/faculty/people/mann.shtml
Original Filename: 1123268256.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Jonathan Overpeck <jto@u.arizona.edu>
To: Tim Osborn <t.osborn@xxxxxxxxx.xxx>
Subject: Re: MWP figure
Date: Fri, 5 Aug 2005 14:57:xxx xxxx xxxx
Cc: Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, Keith Briffa <k.briffa@xxxxxxxxx.xxx>, <oyvind.paasche@xxxxxxxxx.xxx>
<x-flowed>
Hi Tim and Keith - Hope you're not going to kill
me, but I was talking with Susan Solomon today,
and she impressed me with the need to make
several points if we can.
One issue (other to come in a subsequent email)
is whether we can extend the MWP box figure to
include the 15th century. I don't read the blogs
that regularly, but I guess the skeptics are
making hay of their being a global warm event
around 1450AD. I agree w/ Susan that it is our
obligation to weigh in on issues like this,
so.... can we extend the fig to extend up to
1500AD?
Sorry about this, Tim. Of course we need it yesterday.
Thanks x10**6
best, peck
>Dear Eystein, Peck and Keith,
>
>I spotted a minor error in the MWP figure
>(reference period was 1xxx xxxx xxxxbut should have
>been 1xxx xxxx xxxxbecause some series stop in 1980)
>and a typo in the legend, so here is a revised
>MWP figure with these things corrected and a
>slight adjustment to line thicknesses and font
>sizes.
>
>As before I've included .ps, .pdf and .gif
>versions because I'm not sure what you prefer.
>
>I've also drafted a caption - see attached .doc
>file. Feel free to modify as necessary. I
>think it covers the necessary details including
>normalisation period, but perhaps it is a bit
>"wordy" and unnecessarily repeats things already
>in the MWB box text?
>
>I'm still working on SH figure/caption.
>
>Cheers
>
>Tim
>
>
>
>Attachment converted: Macintosh HD:ipccar4_mwpbox 1.pdf (PDF /
Original Filename: 1123513957.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Jonathan Overpeck <jto@u.arizona.edu>
To: Tim Osborn <t.osborn@xxxxxxxxx.xxx>
Subject: Re: MWP figure
Date: Mon, 8 Aug 2005 11:12:xxx xxxx xxxx
Cc: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>, <oyvind.paasche@xxxxxxxxx.xxx>
<x-flowed>
Hi Tim - Decisions, decisions... thanks so much
for taking the initiative. I think - for the
reason you state, we should go for the one that
includes the 20th century. We make clear that
these are not reconstructed temp, but normalized
anomalies - this keeps us out of some trouble.
But, I think the main message is that we're
looking at this issue from every angle. And,
we're letting others see the issue from every
angle. It adds punch.
this means that the MWP box needs to talk about
the period around 1400 - can you make sure that's
on Keith's radar screen. I believe that
historians talk about the Medieval Period going
to at least 1450, so what the heck...
I you can adjust the caption to work, and then
send both it and the final fig to
Original Filename: 1123514677.txt | Return to the index page | Permalink | Earlier Emails | Later Emails
From: Jonathan Overpeck <jto@u.arizona.edu>
To: David Rind <drind@xxxxxxxxx.xxx>
Subject: RE: solar MM
Date: Mon, 8 Aug 2005 11:24:xxx xxxx xxxx
Cc: Keith Briffa <k.briffa@xxxxxxxxx.xxx>, Eystein Jansen <eystein.jansen@xxxxxxxxx.xxx>
David - sounds promising. So, the bottom line is that a little disagreement is ok - that's
a reflection of the real uncertainty? But, the discrepancy is not all that big in the end?
No need to take this to a higher level?
Keith Briffa is back on line and finishing off Section 6.5, so you might want to send him
an email w/ suggestions that help keep chap 6 compatible w/ 2 and 9 - for example, with
respect to solar, we acknowledge the forcing could be less than 0.5 W/m**2, and the
uncertaintly wrt to trop aerosols and land albedo is significant - we could easily be
closer to chap 9's estimate. Would you say the key is that our analysis acknowledge the
uncertainty so as to overlap well with the other chapters?
Keith - please make sure you send your new 6.5 to David too - while you were out, he was
working hard w/ chap 2 and 9 to make sure we (the IPCC) avoid saying things that confuse.
The comparison of radiative forcings from 3 different angles is what assessment is all
about, and it's great David has had the patience to help figure it all out.
Thx, Peck
Hi Gabi,
The key to your proposed solution is the updated numbers from Chapter 2. If indeed the
radiative forcing change to 1750 is -1.53, then presumably you have made this consistent
with the earlier part of Chapter 9. The numbers previously looked like this (I haven't
seen the latest version of 6.5, but I've included the previous estimates we had in the
ZOD):
W/m**2
Chapter xxx xxxx xxxxChapter 9
MM 1750
Greenhouse gases: -2.xxx xxxx xxxx.6
TROP aerosols: 0.xxx xxxx xxxx.2
Solar -0.xxx xxxx xxxx.1
Volcanic: ? ?
Land albedo: +0.xxx xxxx xxxx.03
Trop O3: -0.xxx xxxx xxxx.4
Strat O3: +0.xxx xxxx xxxx.10
1'st indirect aerosol forcing 1.2
STRAT H2O -0.13
AVIATION -0.02
TOTAL -2.xxx xxxx xxxx.7
There is essentially no change in greenhouse gas forcing from 1750 to 1700 (see for
example Crowley et al., GRL, 2003), so the difference in the estimated numbers is
probably due to inclusion of more things or different choices in Chapter 2. A similar
statement holds for trop aerosols. One can also use these two to presume that the same
also holds true for land albedo. [The value listed for that in Chapter 9 is quite small
compared to some other studies; e.g., Govindasamy et al., GRL, 28, xxx xxxx xxxx,2001.] So, to
the extent these numbers are still discussed in Chapter 6, they should be made
consistent with those in chapters 2 and 9.
With respect to your proposed paragraph below: I would drop the comments about trace gas
differences but saying land albedo changes may have been greater, along with the
additional solar change, could give us the -1.8 W/m**2 forcing.
Concerning the temperature response: the Moberg et al paper itself claims 1