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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.
P
The Pacific decadal oscillation (PDO) is a pattern of Pacific climate variability that shifts phases on at least inter-decadal time scale, usually about 20 to 30 years. The PDO is detected as warm or cool surface waters in the Pacific Ocean, north of 20° N. During a "warm", or "positive", phase, the west Pacific becomes cool and part of the eastern ocean warms; during a "cool" or "negative" phase, the opposite pattern occurs.
The Pacific (inter-)decadal oscillation was named by Steven R. Hare, who noticed it while studying salmon production patterns the results in 1997.
The mechanism by which the pattern lasts over several years has not been identified; one suggestion is that a thin layer of warm water during summer may shield deeper cold waters. A PDO signal has been reconstructed to 1661 through tree-ring chronologies in the Baja California area.[2]
The interdecadal Pacific oscillation (IPO or ID) display similar sea-surface temperature (SST) and sea-level pressure (SLP) patterns, with a cycle of 15–30 years, but affects both the north and south Pacific. In the tropical Pacific, maximum SST anomalies are found away from the equator. This is quite different from the quasi-decadal oscillation (QDO) with a period of 8-to-12 years and maximum SST anomalies straddling the equator, thus resembling the El Niño-Southern Oscillation (ENSO).
Regime shifts
Although there are several patterns of behavior, the most significant one seems to be in regime shifts between "warm" and "cool" patterns which last 5 to 20 years.
- 1750: PDO displays an unusually strong oscillation.
- 1905: After a strong swing, PDO changed to a "warm" phase.
- 1946: PDO changed to a "cool" phase. [See the blue section of the graph on the right]
- 1977: PDO changed to a "warm" phase.
- 1998: PDO index showed several years of "cool" values, but did not remain in that pattern.
- 2008: The early stages of a cool phase of the basin-wide Pacific Decadal Oscillation.
In all cases in the 1900s, PDO "regime shifts" were related to similar changes in the tropical ocean.
Observed monthly values for the PDO (1900–present).
Reconstructed PDO (1660–1991).
Last changed: 9th February, 2010 at 17:31:31
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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.
