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Kevin Trenberth to Michael Mann, Oct 12, 2009:
The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t. The CERES data published in the August BAMS 09 supplement on 2008 shows there should be even more warming: but the data are surely wrong. Our observing system is inadequate.
Kevin Trenberth to Tom Wigley, Oct 14, 2009
Hi Tom
How come you do not agree with a statement that says we are no where close to knowing where
energy is going or whether clouds are changing to make the planet brighter. We are not
close to balancing the energy budget. The fact that we can not account for what is
happening in the climate system makes any consideration of geoengineering quite hopeless as
we will never be able to tell if it is successful or not! It is a travesty!
Kevin
Leo Tolstoy
“I know that most men, including those at ease with problems of the greatest complexity, can seldom accept even the simplest and most obvious truth if it be such as would oblige them to admit the falsity of conclusions which they have delighted in explaining to colleagues, which they have proudly taught to others, and which they have woven, thread by thread, into the fabric of their lives.”
Phil Jones
“We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it.” -
Phil Jones to Michael Mann Feb 21, 2005:
The IPCC comes in for a lot of stick.
Leave it to you to delete as appropriate !
Cheers
Phil
PS I'm getting hassled by a couple of people to release the CRU station temperature data.
Don't any of you three tell anybody that the UK has a Freedom of Information Act !
Tom Wigley to Phil Jones Sep 27, 2009:
If you look at the attached plot you will see that the
land also shows the 1940s blip (as I'm sure you know).
So, if we could reduce the ocean blip by, say, 0.15 degC,
then this would be significant for the global mean — but
we'd still have to explain the land blip.
I've chosen 0.15 here deliberately. This still leaves an
ocean blip, and i think one needs to have some form of
ocean blip to explain the land blip (via either some common
forcing, or ocean forcing land, or vice versa, or all of
these). When you look at other blips, the land blips are
1.5 to 2 times (roughly) the ocean blips — higher sensitivity
plus thermal inertia effects. My 0.15 adjustment leaves things
consistent with this, so you can see where I am coming from.
Removing ENSO does not affect this.
It would be good to remove at least part of the 1940s blip,
but we are still left with "why the blip".
Let me go further. If you look at NH vs SH and the aerosol
effect (qualitatively or with MAGICC) then with a reduced
ocean blip we get continuous warming in the SH, and a cooling
in the NH — just as one would expect with mainly NH aerosols.
The other interesting thing is (as Foukal et al. note — from
MAGICC) that the 1910-40 warming cannot be solar. The Sun can
get at most 10% of this with Wang et al solar, less with Foukal
solar. So this may well be NADW, as Sarah and I noted in 1987
(and also Schlesinger later). A reduced SST blip in the 1940s
makes the 1910-40 warming larger than the SH (which it
currently is not) — but not really enough.
So ... why was the SH so cold around 1910? Another SST problem?
(SH/NH data also attached.)
This stuff is in a report I am writing for EPRI, so I'd
appreciate any comments you (and Ben) might have.
Tom.
Tim Osborn to Michael Mann and Ian Macadam , Oct 5, 1999:
Dear Mike and Ian
Keith has asked me to send you a timeseries for the IPCC multi-proxy
reconstruction figure, to replace the one you currently have. The data are
attached to this e-mail. They go from 1402 to 1995, although we usually
stop the series in 1960 because of the recent non-temperature signal that
is superimposed on the tree-ring data that we use. I haven't put a 40-yr
smoothing through them - I thought it best if you were to do this to ensure
the same filter was used for all curves.
Keith Briffa:
Briffa:
For the record, I do believe that the proxy data do show unusually
>warm conditions in recent decades. I am not sure that this unusual warming
>is so clear in the summer responsive data. I believe that the recent warmth
>was probably matched about 1000 years ago. I do not believe that global
>mean annual temperatures have simply cooled progressively over thousands of
>years as Mike appears to and I contend that that there is strong evidence
>for major changes in climate over the Holocene (not Milankovich) that
>require explanation and that could represent part of the current or future
>background variability of our climate. I think the Venice meeting will be
>a good place to air these isssues.
Latest News (hidethedecline)
A brief check indicates a "warm MWP-consensus" before IPCC published the Mann hockey stick graph in 2001. But after 2001, results on MWP seems to approach the IPCC viewpoint.
In April 2009 I collected a series of results concerning Holocene, Historic and recent temperatures for an article on WATTS.
Here I found approximately 54 datasets (almost 100% peer reviewed results) that i used for analysing claimed difference on MWP on the Northern vs. the Southern hemisphere. I also used the 54 datasets to see if the tree ring method has an impact on MWP results.
Another aspect of MWP-results caught my interest:
fig. 1.
Its often debated how IPCC changed viewpoint concerning the Medieval Warm Period in 2001.
- Was the pre-2001 MWP viewpoint simply "wrong" ?
- When IPCC launched their new viewpoint on MWP in 2001, was this new viewpoint in fact the consensus in 2001?
- Or did IPCC actually claim to "know" better than the consensus in 2001?
- What is the consensus on MWP today?
- And finaly, did results after IPCC change of viewpoint in 2001 has changed, how can this be explained?
Here are the 54 temperature datasets covering the MWP divided in two groups :
1) 1976-2000 vs 2) 2001-2009
fig. 2. (Geographical origin see)
First we see that both 1) or 2) shows a MWP warmer than today. (This is partly due to my criteria for the 54 datasets: Max 15% tree ring data, due to possible problems with tree ring data and thus a need to see data not dominated by this one method. Quite a few of the excluded tree data are frequently used by IPCC yielding the well known hockey shapes from IPCC AR4, 2007.)
Second we see a MWP for group 1) 1976-2000 more than twice as warm compared to recent years as group 2) 2001-2009. A significant, and for me surprising finding. And the distance between 1) and the IPCC hockey sticks with all the tree graphs of recent years is even bigger.
One might argue that the data choice for my Watts article was not quantitative fully exact etc etc. But i simply cannot come up with any explanation for such a big change in the trend of results when just dividing on year of publishing. Therefore I will assume that there is in fact a development in results on MWP after 2001.
Further, if you compare graph 1) 1976-2000 on fig. 2 with the original temperature graph IPCC 1990-2001 on fig.1. - then you will see a stunning match. This indicates that the consensus of a WARM middle age before year 2001 was likely to be a real consensus. If true:
How could IPCC publish the hockey stick in 2001 and ignore the consensus at the time?
Yes, later came several results that confirmed the IPCC 2001 Opinion - Hockey sticks, mainly tree lines, but... could IPCC see the future? Or how could IPCC know what future results on MWP would be?
Well of cause, if the conclusions of "climate gate" are even remotely true, then one would guess that IPCC controlled some of the future results and this would explain all.
Last changed: 9th March, 2010 at 19:55:05
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Kevin Trenberth to Michael Mann, Oct 12, 2009:
The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t. The CERES data published in the August BAMS 09 supplement on 2008 shows there should be even more warming: but the data are surely wrong. Our observing system is inadequate.
Kevin Trenberth to Tom Wigley, Oct 14, 2009
Hi Tom
How come you do not agree with a statement that says we are no where close to knowing where
energy is going or whether clouds are changing to make the planet brighter. We are not
close to balancing the energy budget. The fact that we can not account for what is
happening in the climate system makes any consideration of geoengineering quite hopeless as
we will never be able to tell if it is successful or not! It is a travesty!
Kevin
Leo Tolstoy
“I know that most men, including those at ease with problems of the greatest complexity, can seldom accept even the simplest and most obvious truth if it be such as would oblige them to admit the falsity of conclusions which they have delighted in explaining to colleagues, which they have proudly taught to others, and which they have woven, thread by thread, into the fabric of their lives.”
Phil Jones
“We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it.” -
Phil Jones to Michael Mann Feb 21, 2005:
The IPCC comes in for a lot of stick.
Leave it to you to delete as appropriate !
Cheers
Phil
PS I'm getting hassled by a couple of people to release the CRU station temperature data.
Don't any of you three tell anybody that the UK has a Freedom of Information Act !
Tom Wigley to Phil Jones Sep 27, 2009:
If you look at the attached plot you will see that the
land also shows the 1940s blip (as I'm sure you know).
So, if we could reduce the ocean blip by, say, 0.15 degC,
then this would be significant for the global mean — but
we'd still have to explain the land blip.
I've chosen 0.15 here deliberately. This still leaves an
ocean blip, and i think one needs to have some form of
ocean blip to explain the land blip (via either some common
forcing, or ocean forcing land, or vice versa, or all of
these). When you look at other blips, the land blips are
1.5 to 2 times (roughly) the ocean blips — higher sensitivity
plus thermal inertia effects. My 0.15 adjustment leaves things
consistent with this, so you can see where I am coming from.
Removing ENSO does not affect this.
It would be good to remove at least part of the 1940s blip,
but we are still left with "why the blip".
Let me go further. If you look at NH vs SH and the aerosol
effect (qualitatively or with MAGICC) then with a reduced
ocean blip we get continuous warming in the SH, and a cooling
in the NH — just as one would expect with mainly NH aerosols.
The other interesting thing is (as Foukal et al. note — from
MAGICC) that the 1910-40 warming cannot be solar. The Sun can
get at most 10% of this with Wang et al solar, less with Foukal
solar. So this may well be NADW, as Sarah and I noted in 1987
(and also Schlesinger later). A reduced SST blip in the 1940s
makes the 1910-40 warming larger than the SH (which it
currently is not) — but not really enough.
So ... why was the SH so cold around 1910? Another SST problem?
(SH/NH data also attached.)
This stuff is in a report I am writing for EPRI, so I'd
appreciate any comments you (and Ben) might have.
Tom.
Tim Osborn to Michael Mann and Ian Macadam , Oct 5, 1999:
Dear Mike and Ian
Keith has asked me to send you a timeseries for the IPCC multi-proxy
reconstruction figure, to replace the one you currently have. The data are
attached to this e-mail. They go from 1402 to 1995, although we usually
stop the series in 1960 because of the recent non-temperature signal that
is superimposed on the tree-ring data that we use. I haven't put a 40-yr
smoothing through them - I thought it best if you were to do this to ensure
the same filter was used for all curves.
Keith Briffa:
Briffa:
> For the record, I do believe that the proxy data do show unusually
>warm conditions in recent decades. I am not sure that this unusual warming
>is so clear in the summer responsive data. I believe that the recent warmth
>was probably matched about 1000 years ago. I do not believe that global
>mean annual temperatures have simply cooled progressively over thousands of
>years as Mike appears to and I contend that that there is strong evidence
>for major changes in climate over the Holocene (not Milankovich) that
>require explanation and that could represent part of the current or future
>background variability of our climate. I think the Venice meeting will be
>a good place to air these isssues.
