Survey of Swedish climate scientists

[Erik Svensson, Göteborg]

http://uppsalainitiativet.blogspot.com/2010/04/overwhelming-majority-of-swedish.html

At least in Sweden, is seems like the opinions among climate
scientists have not changed due to the 'climategate'-thing.

[Jason Sale]

I don't think Sweden is alone: http://www.warmdebate.com/forum/ipcc-seeks-help

Although there are exceptions, I think most scientists will agree that
climategate was a media-driven exaggeration. Whether or not the
mistakes were serious enough to warrant any real loss of credibility
may or may not be a serious discussion, but the degree to which the
media went to town with this story is completely unjustified.

On Apr 13, 12:04 am, Erik Svensson, Göteborg <e...@chem.gu.se> wrote:
> http://uppsalainitiativet.blogspot.com/2010/04/overwhelming-majority-...

[The Cunctator]

Are there exceptions? Are there any climate scientists whose opinion of the science changed?

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[Erik Svensson]

Of course there is nothing strange with the results here, it's just
nice that the issue gets settled. The Swedish denialists (as well as
the others) have imagined that some kind of hidden majority of climate
researchers really secretly do not believe in AGW. The denialists
centered around Stockholm Initiative and 'The Climate Scam' blog seem
to be quite frustrated right now.

[Tom Adams]

Judith Curry's views have evolved, but the change might have been due
to the flap over GW causing hurricanes:

http://discovermagazine.com/2010/apr/10-it.s-gettin-hot-in-here-big-battle-over-climate-science

On Apr 12, 8:28 pm, The Cunctator <cuncta...@gmail.com> wrote:
> Are there exceptions? Are there any climate scientists whose opinion of the
> science changed?
>

> > To unsubscribe, reply using "remove me" as the subject.- Hide quoted text -
>
> - Show quoted text -

[Robert I Ellison]

Judith Curry's bumps and changes in climate must be understood rather
than simply labelled as natural variability and neglected - as it has
been for too long and indeed by the IPCC. The IPCC is wrong at the
level of underlying assumptions about how climate works - ordered and
simple physics rather than as a complex and dynamic system. The
'naive hubris' of the 'scientific consensus' is playing into the hands
of skeptics. It astonishes me because the climate models are
themselves chaotic - using as they do the same equations of fluid
motion that Edward Lorenz did in the 1960's when he discovered chaos
theory in a model of convection. But it just seems to go right over
their heads - or in one ear and out the other - for some reason I
don't care to speculate on other than the usual tragedy of the human
condition - brought on by the human tendency to self delusion and a
lack of scientific skepticism. Let's have a show of hands -how many
believe in simple climate physics? 97%?. You guys have really blown
it.

http://www.redstate.com/vladimir/2010/03/15/antarctic-shrimp-global-warming-and-the-laffer-curve/

But chaos theory implies that climate is sensitive to small changes in
initial conditions - such that there is a risk of sudden and
catastrophic climate change at any time at all.

On Apr 13, 12:04 am, Erik Svensson, Göteborg <e...@chem.gu.se> wrote:
> http://uppsalainitiativet.blogspot.com/2010/04/overwhelming-majority-...
>

[Eric Swanson]

Robert, Your response does not follow the thread. The linked article
refers to a pole of climate scientists in SWEDEN! Judith Curry is a US
based researcher. And, you link to a post on the ultra conservative
blog, Redstate.com, written by a person who describes himself as:
"Operations Manager for a small Gulf of Mexico oil & gas explorer &
producer".

Aren't you just trolling for some sort of recognition of your
unsupported denialist point of view? All your comments about chaos
ignore the fact that if the climate is as unstable as you claim, there
would be large swings year-to-year and any man made changes would
easily set off major changes beyond what's been seen in the climate
record of the Holocene. If the climate system is as unstable as you
appear to believe, then it is major folly to perturb it by adding more
greenhouse gases. That would provide an even more urgent reason for
action to minimize emissions, if true.

E. S.
-------------------------------------------------------------------------

[Alastair]

Eric,

Robert's oil man was saying the same as Judith Curry - the scientists
suffer from too much hubris! So much hubris that even Judith Curry
(JC) won't admit the climate is chaotic. She blames the non-linear
fluctuations on cycles.

Note, there ARE swings from year to year in global and more so in
local climate. El Nino and hurricanes are examples of that. Just
because we have a name for them does not mean that they are not
example of chaos. On a macro-climatic scale, the end of the LGM, and
the start and end of the Younger Dryas were all violent changes. While
parts of the earth remain glaciated there is every possibility of yet
another violent change of that order happening again.

BTW, if you want to see chaos in action visit slide 13 of this
presentaion by JC
http://ametsoc.org/atmospolicy/documents/October252005JudithCurry.pdf

But a lot of what JC says is true. Michael Mann is too young to know
that it was Phil Jones who came up with the idea that the cooling
during the 1950s and 60s could be explained away using aerosols. Add
the right amount for the right time and then you have a nice straight
line to blame on CO2. Obviously JC is not fooled, but that does not
alter the fact that there was warming in the early and the late parts
of the 20gh century. The Arctic sea ice and now the Greenland ice
sheet are melting. If we do not REDUCE the levels of greenhouse gases
in the atmosphere then every city port in the world will suffer a 20
foot rise in sea level. It may take 100 years but it is unstoppable!

How does JC think we are going to persuade the public to take action
and give up their automobiles, if the scientist say they have doubts.
JC's problem is that, like most of her US compatriots, she is an
optimist and believes it will never happen.

If you want the truth you have to come to this side of the pond. Our
empire has collapsed and our optimism gone with it :-( James Lovelock
(JL), like JC, is also skeptical of the science of scientists. He
remembers the white washing of the ozone threat, now long forgotten
amongst in hubris displayed as a result of the Montreal treaty. See:
http://www.guardian.co.uk/environment/blog/2010/mar/29/james-lovelock

I have to admit I have not read the whole article but what I have read
either agrees with what I already knew or makes sense to me.

Enjoy everyone, that's what he recommends!

Cheers, Alastair.

> >http://www.redstate.com/vladimir/2010/03/15/antarctic-shrimp-global-w...

[Robert I Ellison]

Eric,

You want to limit the topic to 69 Swedish scientists? LOL. As you
know, I think the reality is abrupt climate change rather than global
warming as such. I don't minimise for a moment the risk of abrupt
climate change but many others will - as does the 'ultra conservative'
blog I linked to. They are, however, right about climate change and
complex systems and the Swedish scientists are wrong about global
warming. Far from being unsupported - there are thousands of papers
that document abrupt climate change at all timescales. Everyone knows
about it but it just doesn't seem to translate often enough into the
only reasonable theory possible. FYI - the Curry article was
introduced by another but contains valid points (which you need to
take on board) nonetheless.

A few minor points.

1. There may be a groupthink amongst 69 Swedish left wing liberal
'climatologists' that the IPCC is right but if the IPCC is wrong - as
they are at the level of underlying assumptions (assuming a steady
evolution of climate this century rather than abrupt change) - then
the groupthink is merely 'naive hubris' stemming from self delusion
and a lack of scepticism.

2. There are major year to year swings in climate - influenced
primarily by ENSO - itself a complex system. There are even larger
shifts at 2 to 3 decade intervals. The 1976/1977 'Great Pacific
Climate Shift' is an extraordinarily well documented case in point but
there are many others.

3. The Holocene commenced some 12,000 years ago at the end of the
last glacial period. There was a major abrupt shift since to near
glacial conditions and back again (10's of degrees in Ireland over as
little as months) known as the Younger Dryas which lasted for 1300
years. A quick reference to Holocene temperature at Wikepedia -
http://en.wikipedia.org/wiki/File:Holocene_Temperature_Variations.png
- shows that Holocene climate 'stability' is an illusion - or delusion
- take your pick. You say that climate in the Holocene doesn’t vary
enough to demonstrate climate instability? You’re being
absurd.

4. Abrupt climate change rather than the steady evolution of global
warming is the reality. But my point is that a foolish clinging to
the global warming paradigm will undermine the case for emission
reductions for a generation or 2 - as I suggested prior to the link to
the 'ultra conservative' blog. Climate is potentially much more
unstable than thought by most until now.

5. I don't know how to turn this around until people such as yourself
accept that climate is a complex and dynamic system which is chaotic
(in the sense of chaos theory) in nature at all time scales. The IPCC
for instance accepts that 'weather' is chaotic but says that the
average of chaotic states (climate) is not chaotic - at least at the
scale of the instrumental record. It is so obviously wrong that I
can't characterise it as anything other than delusional.

The first article I came across (in 1990) which documented an abrupt
climate change was on flood and drought dominated regimes in
Australia. A couple of geomorphologists noticed that streams had
changed shape after the mid 1970's. This is a result of large and
abrupt changes in rainfall regimes. It is associated with conditions
in the Pacific of course - conditions which influence both rainfall
and temperature globally. These are abrupt (and major) shifts in
climate at multi-decadal timescales – a property of a complex and
dynamic system rather than of simple physics.

I suggest that you have another look at the Curry article (and more)
rather than calling me a denialist sprouting unsupported views. I am
just trying to be absolutely unmistakable - until people get the new
climate paradigm they're sprouting groupthink bullshit, reality will
continue to diverge from theory and we will make no progress on
emissions reductions. Do you want to take the risk that I'm wrong or
do you want to start to understand how complex systems theory applies
to climate?

Robert

> >http://www.redstate.com/vladimir/2010/03/15/antarctic-shrimp-global-w...

>
> > But chaos theory implies that climate is sensitive to small changes in
> > initial conditions - such that there is a risk of sudden and
> > catastrophic climate change at any time at all.
>
> > On Apr 13, 12:04 am, Erik Svensson, Göteborg <e...@chem.gu.se> wrote:
> > >http://uppsalainitiativet.blogspot.com/2010/04/overwhelming-majority-...
>
> > > At least in Sweden, is seems like the opinions among climate

> > > scientists have not changed due to the 'climategate'-thing.- Hide quoted text -

[Eric Swanson]

Robert,

Where did I "Minimize the risk of abrupt climate change"? I think you
need to check your reading comprehension abilities.
You seem to have missed my repeated mention of the possibility of a
shutdown of the THC, which might well happen rather rapidly and thus
appear to be abrupt. Then, too, there's evidence that the THC in the
Greenland Sea did slow or stop in the early 1980's after the Great
Salinity Anomaly, at about the same time your Pacific Oscillation
appeared. I suggest that the change in the Pacific may have been a
result.

May I also point out also that the Holocene began 10,000 years ago,
not 12,000 and the Younger Dryas was over by then. Yes, the YD began
quickly. But, the forcing which caused the YD was related to the
existence of the ice sheets over Canada, a situation which does not
apply in today's climate. Thus, the rapid shutdown of the THC which
is thought to have resulted from catastrophic flooding can not happen
in the same way. There are, however, other mechanisms which could
produce similar results and many climate models do show a weakening of
the THC as GHGs build up.

While we are on the subject, there is indirect evidence that there's
been another weakening or shutdown of the THC in the Greenland Sea for
the past 3 winters. Could have had something to do with the exciting
winter which just visited Europe and parts of the Eastern US. Sad to
say, without direct evidence, I can say no more...

E. S.
---------------

[Robert I Ellison]

Eric,

I think it is generally agreed that the Holocene commenced about
12,000 years ago - i.e the modern interglacial. The Younger Dryas
occurred at the transition - merely an example amongst many of abrupt
climate change. Abrupt changes are by definition nonlinear chaotic
oscillations. As in Alastair's comment - 'So much hubris that even

Judith Curry (JC) won't admit the climate is chaotic. She blames the

non-linear fluctuations on cycles.' A dynamic response to small
changes in initial conditions perhaps?

I think my exact words were - I don't for a moment minimise the risk
of abrupt climate change?

Robert

> > blog I linked to.- Hide quoted text -

>
> - Show quoted text -

[Tom Adams]

On Apr 14, 3:24 pm, Alastair <a...@abmcdonald.freeserve.co.uk> wrote:
> Eric,
>
> Robert's oil man was saying the same as Judith Curry - the scientists
> suffer from too much hubris! So much hubris that even Judith Curry
> (JC) won't admit the climate is chaotic. She blames the non-linear
> fluctuations on cycles.
>
> Note, there ARE swings from year to year in global and more so in
> local climate. El Nino and hurricanes are examples of that. Just
> because we have a name for them does not mean that they are not
> example of chaos. On a macro-climatic scale, the end of the LGM, and
> the start and end of the Younger Dryas were all violent changes. While
> parts of the earth remain glaciated there is every possibility of yet
> another violent change of that order happening again.
>
> BTW, if you want to see chaos in action visit slide 13 of this

> presentaion by JChttp://ametsoc.org/atmospolicy/documents/October252005JudithCurry.pdf

>
> But a lot of what JC says is true. Michael Mann is too young to know
> that it was Phil Jones who came up with the idea that the cooling
> during the 1950s and 60s could be explained away using aerosols. Add
> the right amount for the right time and then you have a nice straight
> line to blame on CO2.  Obviously JC is not fooled, but that does not
> alter the fact that there was warming in the early and the late parts
> of the 20gh century.  The Arctic sea ice and now the Greenland ice
> sheet are melting. If we do not REDUCE the levels of greenhouse gases
> in the atmosphere then every city port in the world will suffer a 20
> foot rise in sea level. It may take 100 years but it is unstoppable!
>
> How does JC think we are going to persuade the public to take action
> and give up their automobiles, if the scientist say they have doubts.

Scientist should properly represent the uncertainties and let the
chips fall where they may. One of JC's points is that some skeptic
will properly represent the uncertainties if the scientists don't, and
the skeptic will thereby get the credibility.

In rebuttal to JC, Mann made the point in the Discover article that
uncertainty cuts both ways.

> JC's problem is that, like most of her US compatriots, she is an
> optimist and believes it will never happen.

Actually she is pessimistic that the current approach by scientists
will
work.

> > > > scientists have not changed due to the 'climategate'-thing.- Hide quoted text -

[Tom Adams]

On Apr 13, 9:18 pm, Robert I Ellison <rob...@robertellison.com.au>
wrote:

> Judith Curry's bumps and changes in climate must be understood rather
> than simply labelled as natural variability and neglected - as it has
> been for too long and indeed by the IPCC.  The IPCC is wrong at the
> level of underlying assumptions about how climate works - ordered and
> simple physics rather than as a complex and dynamic system.  The
> 'naive hubris' of the 'scientific consensus' is playing into the hands
> of skeptics.  It astonishes me because the climate models are
> themselves chaotic - using as they do the same equations of fluid
> motion that Edward Lorenz did in the 1960's when he discovered chaos
> theory in a model of convection.  But it just seems to go right over
> their heads - or in one ear and out the other - for some reason I
> don't care to speculate on other than the usual tragedy of the human
> condition - brought on by the human tendency to self delusion and a
> lack of scientific skepticism.  Let's have a show of hands -how many
> believe in simple climate physics? 97%?.  You guys have really blown
> it.
>

> http://www.redstate.com/vladimir/2010/03/15/antarctic-shrimp-global-w...

>
> But chaos theory implies that climate is sensitive to small changes in
> initial conditions - such that there is a risk of sudden and
> catastrophic climate change at any time at all.

A system can be chaotic on a short time frame but it can still
evidence very predictable average behavior over a long time frame.

I think there is a distinction between a system that has some tipping
points and a system that is chaotic.

>
> On Apr 13, 12:04 am, Erik Svensson, Göteborg <e...@chem.gu.se> wrote:
>
>
>
> >http://uppsalainitiativet.blogspot.com/2010/04/overwhelming-majority-...
>
> > At least in Sweden, is seems like the opinions among climate

[Alastair]

On Apr 16, 4:02 pm, Tom Adams <tadams...@yahoo.com> wrote:

> Scientist should properly represent the uncertainties and let the
> chips fall where they may.

That is like saying that you should play by the Marquess of
Queensberry rules
http://en.wikipedia.org/wiki/Marquess_of_Queensberry_rules
when trying to stop an armed robber!

Of course there is uncertainty, and thing might turn out mush worse
than is currently being predicted. The scientists have to point out
the dangers. The sceptics will point out the uncertainties but not
the dangers.

Cheers, Alastair.

[Robert I Ellison]

But are tipping points predictable? Chaos theory is a simply a
metatheory of change in complex systems and a climate 'tipping point'
is merely an example of chaotic bifurcation in a complex and dynamical
system. Small initial changes lead to a change in one component which
drives change in another etc. A 'cascade of powerful mechanisms'
leading to a nonlinear climate response. Abrupt climate change,
tipping points, chaotic bifurcation and sensitive dependence all have
the same meaning.

I think climate is chaotic at all time scales - in the multidecadal
timescale as in https://pantherfile.uwm.edu/kravtsov/www/downloads/GRL-Tsonis.pdf

Major climate shifts around 1910, the mid 1940's, the late 1970's and,
in a later paper(Has climate recently shifted? Swanson and Tsonis
2009), 1998/2001. And please note that changes are evident in real
world data and are extensively documented in scientific literature.
Climate is not chaotic only in the short term - as in weather - but at
every scale from ENSO to decades, ice ages and beyond.

Climate models are themselves chaotic - http://www.pnas.org/content/104/21/8709.full.pdf
- suffering not only from 'sensitive dependence' but from 'structural
instability'. The latter involves chaotic bifurcation as a result of
small changes (well within the limits of quantification) of boundary
conditions. There is thus no unique solution to the climate problem
within the constraints of present day understanding. Modellers pick
their best run subjectively and send it to the IPCC where it is
graphed along with a number of other subjectively selected
'solutions'. Very average indeed.

So we are 'predicting' a chaotic system by means of another, and
different, chaotic system? Give me a break. 'The science' has got it
wrong at the level of underlying assumptions - mindless repetition of
the error leads us nowhere.

> For more options, visit this group athttp://groups.google.com/group/globalchange- Hide quoted text -

[David B. Benson]

On Apr 16, 5:01 pm, Robert I Ellison <rob...@robertellison.com.au>
wrote:
> ...

> Major climate shifts around 1910, the mid 1940's, the late 1970's and,

> ...
From
http://www.realclimate.org/index.php/archives/2010/03/unforced-variations-3/comment-page-12/#comment-168530
we can see that the so-called shifts around 1910s and 1940s are well
esplained as internal variabity while that of the 1970s is driven by
CO2.

[Robert I Ellison]

The reality is abrupt climate change rahter than the steady evolution
of climate. Miniscule changes (over a year or 3) of CO2 cannot
explain sudden and dramatic shifts in climate. It is foolishness to
believe so. The underlying physical principle is the theory of
complex and dynamic systems and sensitive dependence rather than the
simple physics of spectrograqphic adsorption and simple cause and
effect.

On Apr 19, 11:04 am, "David B. Benson" <dben...@eecs.wsu.edu> wrote:
> On Apr 16, 5:01 pm, Robert I Ellison <rob...@robertellison.com.au>
> wrote:> ...
> > Major climate shifts around 1910, the mid 1940's, the late 1970's and,
> > ...
>

> Fromhttp://www.realclimate.org/index.php/archives/2010/03/unforced-variat...

[Robert I Ellison]

David,

Sorry - meant to finish this rather then send.

The formula you use is unintelligible. In between the missing
brackets, undefined terms and dimensionaly impossible mathematics
(e.g. ln(PPM) - ln(PPM) - degrees K ?) - let's try to see how it
works.

You estimate the 'observed' (???) global temperature response to a
doubling of CO2 (???) as 2.28 degrees K - so your formula is:

delta global temperature (doubling of CO2) = 2.28 ln 2 = 1.58 degrees
C. I see, not much of a problem at all and consistent with the low
end of the models?

So we get a temperature increase of 1.58 degrees (K or C whatever) for
a doubling of CO2 - but where you have already 'estimated' it as
2.28. Not only circular reasoning but circular reasoning that arrives
at an inconsistant answer.

The Arrhenius formula is:

delta global temperature = gamma X delta forcing = gamma X alpha X ln
(CO2/CO1) - where alpha is estimated empirically at 5.35 in Arrhenius'
calculation. An empirical result (from laboratory results) I believe
and and not related at all to 'so-called' climate sensitivity to
doubling of CO2.

Calculating gamma is a different exercise.

delta forcing = 5.35 ln(380/280) = 1.6 W/m2 - not remarkably the IPCC
CO2 forcing for CO2 in the past 130 years.

delta T = 0.7 degrees C (observed temperature increase) = gamma X 1.6
=> gamma = 0.42 => gamma X alpha = 2.30 - a little different from your
2.28 but essentially the same except arrived at logically and without
the leap into dimensional inconsistencies.

I define the relationship in terms of temperature observations but
wouldn't dream of then correlating to observation. You do see this
fundamental problem I hope? I rather think you need to add also other
forcings and feedbacks. If it were as simple as you suggest - there
would not be a complex problem.

And surely you should understand that the 120 year old science of
Arrhenius needs to be understood in the light of 21st century
physics? You blithely talk about 'well explained' (but undefined)
'internal variability' around 1910 and the mid 1940's - but claim on
the basis of simple and misguided calculations that the abrupt 'Great
Pacific Climate Shift' of 1976/1977 was driven by CO2. You need to
get a wider perspective. I think you should define what you mean by
'internal variability' and then try to explain the underlying physics
to yourself - and not simply by naming it as ENSO, the AMO or some
other physical manifestation of an abrupt and nonlinear climate
oscillation.

Cheers
Robert

On Apr 19, 11:04 am, "David B. Benson" <dben...@eecs.wsu.edu> wrote:

> On Apr 16, 5:01 pm, Robert I Ellison <rob...@robertellison.com.au>
> wrote:> ...
> > Major climate shifts around 1910, the mid 1940's, the late 1970's and,
> > ...
>

> Fromhttp://www.realclimate.org/index.php/archives/2010/03/unforced-variat...

[Tom Adams]

On Apr 16, 8:01 pm, Robert I Ellison <rob...@robertellison.com.au>
wrote:

> But are tipping points predictable?

Some are can be predicted very precisely. Some cannot.

> Chaos theory is a simply a
> metatheory of change in complex systems and a climate 'tipping point'
> is merely an example of chaotic bifurcation in a complex and dynamical
> system.

Where did you get that mish-mash of concepts?

Chaos theory is about systems that are very sensitive to initial
conditions.

A tipping point is a point where a system goes from one stable state
to
another. The system need not be chaotic.

Two different concepts.

Also, any system is unpredictable if you cannot sufficiently specify
the initial conditions. Hence an all unpredictable systems should not
be mashed in with chaotic systems.

[Tom Adams]

On Apr 16, 8:01 pm, Robert I Ellison <rob...@robertellison.com.au>
wrote:

> But are tipping points predictable?

Some are and some are not. Something that varies can have both
predictable and unpredictable tipping points and everything in
between.

Tipping points can be unpredictable due to chaotic processes or due to
mere randomness.

I am arguing that you need to use scientific definitions, not
metaphors or the everyday meanings of terms. There are 2 different
things:

1. Chaotic processes
2. Tipping points

You are probably understating the importance of tipping points by
confusing them with chaotic processes.

> Chaos theory is a simply a
> metatheory of change in complex systems and a climate 'tipping point'
> is merely an example of chaotic bifurcation in a complex and dynamical
> system.

Not true.

> Small initial changes lead to a change in one component which
> drives change in another etc.  A 'cascade of powerful mechanisms'
> leading to a nonlinear climate response. Abrupt climate change,
> tipping points, chaotic bifurcation and sensitive dependence all have
> the same meaning.

Not true.

>
> I think climate is chaotic at all time scales - in the multidecadal
> timescale as inhttps://pantherfile.uwm.edu/kravtsov/www/downloads/GRL-Tsonis.pdf

There do seem to be multidecadal chaotic processes.

We don't have much evidence on longer time scales.

*All* time scales? Kinda a broad claim.

Of course you are right that the idea of climate being the average of
the weather must be bunk or an approximation of limited applicability
at best. The climate parameters do keep changing on all time scales
till there is no climate.

>
> Major climate shifts around 1910, the mid 1940's, the late 1970's and,
> in a later paper(Has climate recently shifted? Swanson and Tsonis
> 2009), 1998/2001.  And please note that changes are evident in real
> world data and are extensively documented in scientific literature.
> Climate is not chaotic only in the short term - as in weather - but at
> every scale from ENSO to decades, ice ages and beyond.
>

> Climate models are themselves chaotic -http://www.pnas.org/content/104/21/8709.full.pdf

> - suffering not only from 'sensitive dependence' but from 'structural
> instability'.  The latter involves chaotic bifurcation as a result of
> small changes (well within the limits of quantification) of boundary
> conditions.

Can you give an example?

I think you are confusing chaotic processes with processes that are
difficult to predict because we have low accuracy of the initial
conditions, but I am not sure.

> There is thus no unique solution to the climate problem
> within the constraints of present day understanding.

Isn't that true for plenty of non-chaotic processes?

> Modellers pick
> their best run subjectively and send it to the IPCC where it is
> graphed along with a number of other subjectively selected
> 'solutions'. Very average indeed.
>
> So we are 'predicting' a chaotic system by means of another, and
> different, chaotic system?  Give me a break.  'The science' has got it
> wrong at the level of underlying assumptions - mindless repetition of
> the error leads us nowhere.

[Robert I Ellison]

I think chaos theory is unfortunately named - it is not chaotic as in
the dictionary definition of chaos. People have more recently been
recasting chaos theory as the theory of complex and dynamic systems.
No complex dynamical system is unpredictable in theory - but is
completely deterministic if we knew enough about the system. As I
said - it is one change influencing an aspect of the system, which
influences another etc. The end result is abrupt and nonlinear change
as a result of the initial changes - sensitive dependence to initial
conditions.

The definition of abrupt climate change is given in a 2002 US National
Academy of Science report - Abrupt climate change: Inevitable
Surprises. It is a sudden and nonlinear change to a new state that
persists for a while. Which might also describe tipping points and
chaotic (as in chaos theory) bifurcation.

There are a few links to the science of abrupt climate change here.
You would do well to try to understand before chiming in with such ill-
considered remarks.

http://www.earthandocean.robertellison.com.au/

[David B. Benson]

On Apr 19, 7:04 pm, Robert I Ellison <rob...@robertellison.com.au>
wrote:
> The formula you use is ...
AE(d) = k(lnCO2(d-1) - lnCO2(1870s)) - GTA(1880s)
but in which an obvious right parenthsis was
missing. There are no undefined terms and the
constant k is estimated for best fit to the
data as is subsequently mentioned.

The OGTR is a transient response and is, as
pointed out, in agreement with an equilibrium
sensitivity of about 3 K.

> Arrhenius needs to be understood in the light of 21st century physics?

Yes and all has been settled since the 1970s; the
Arrenhius approximation is still considered good
enough to appear in IPCC AR4.

Internal variability consists of ENSO, etc., but
by taking decadal averages all that is needed is
the AMO; if you bothered to read about it you would
have discovered it is strongly affected by MOC rate.

Othr forcings need not be considered as the steady
ones all cancel out; see IPCC AR4. The random ones
are reflected in the AMO.

The abrupt shifts seen in Greenland ice cores are
clearly the results of the dynamics of those portions
of the cryosphere that we now longer have with us.

[Robert I Ellison]

The climate models use the same Navier-Stokes equations of fluid
motion that Edward Lorenz used in his convection model. McWilliams
describes both 'sensitive dependence' and 'structural instability' in
the 2007 NAS paper linked to.

http://www.nap.edu/openbook.php?record_id=10136&page=R5

'Large, abrupt climate changes have repeatedly affected much or all of
the earth, locally reaching as much as 10°C change in 10 years.
Available evidence suggests that abrupt climate changes are not only
possible but likely in the future, potentially with large impacts on
ecosystems and societies.

'This report is an attempt to describe what is known about abrupt
climate changes and their impacts, based on paleoclimate proxies,
historical observations, and modeling. The report does not focus on
large, abrupt causes—nuclear wars or giant meteorite impacts—but
rather on the surprising new findings that abrupt climate change can
occur when gradual causes push the earth system across a threshold.
Just as the slowly increasing pressure of a finger eventually flips a
switch and turns on a light, the slow effects of drifting continents
or wobbling orbits or changing atmospheric composition may “switch”
the climate to a new state. And, just as a moving hand is more likely
than a stationary one to encounter and flip a switch, faster earth-
system changes—whether natural or human-caused—are likely to increase
the probability of encountering a threshold that triggers a still
faster climate shift.

We do not yet understand abrupt climate changes well enough to predict
them.'

Abrupt climate change, tipping points or chaotic bifurcation?
Basically - I think you making it up as you go along.

[Erik Svensson]

The SVT has made a follow-up study on the scientific literature:
http://uppsalainitiativet.blogspot.com/2010/04/swedish-television-goes-oreskes-on.html

[Robert I Ellison]

You have posted this bizarre analysis in a comment at real climate.
It is pseudo science that somehow links Arrhenius and the Atlantic
Multidecadal Oscillation. Expecting me to take it seriously would
require a proper methodology, proper referencing and peer reviewed
publication. Let me know when you publish it.

[magnus w]

A follow up by the Swedish television "doing an Oreskes" this I think
is a really good example of a media initiative that takes the question
seriously.

http://uppsalainitiativet.blogspot.com/2010/04/swedish-television-goes-oreskes-on.html

On 12 Apr, 16:04, Erik Svensson, Göteborg <e...@chem.gu.se> wrote:
> http://uppsalainitiativet.blogspot.com/2010/04/overwhelming-majority-...
>

> At least in Sweden, is seems like the opinions among climate
> scientists have not changed due to the 'climategate'-thing.

[Eric Swanson]

Robert,

Yes, there are instances of large, abrupt changes in the paleoclimate
record.
However, those changes are usually found to be due to causes which do
not pertain to today's Earth. You are apparently claiming that those
changes are the entirely the result of internal oscillations within
the atmospheric system, which is not at all apparent. The YD, which
you have repeatedly offered as such an abrupt change, was due to Ice
Age conditions that do not now exist. Other large changes, such as
that from really massive volcanic eruptions, are not internal to the
climate system, but external forcings which might push the climate
over a threshold that the system was slowly approaching, but that does
not suggest that we can not understand the climate system absent such
events.

I think your rants continue show a failure to understand the basic
stability of the Earth's climate system, as evidenced by the proxy
records over the past 10,000 years. The problem with global warming
is that we may be pushing the whole system toward a new normal to
which humanity and the rest of the natural world may not be able to
adapt to if some otherwise small push kicks the system past a
threshold. We know that volcanic eruptions happen and any serious
effort to understand climate must look at the paleo data with that in
mind. You have refused to consider the impacts of volcanic eruptions
which I have pointed to in previous posts. You also have refused to
discuss the ocean circulation and the THC, which are known to exhibit
variation which impacts the climate in the atmospheric portion of the
entire climate system. Looking only at various indexes without
seeking understanding of the mechanisms which drive them is either a
fools game or a veiled effort at obfuscation.

E. S.
-----------------------------------------
On Apr 21, 4:28 am, Robert I Ellison <rob...@robertellison.com.au>
wrote:

[Robert I Ellison]

I am sure it is little more complex than you imagine.

'The Atlantic Ocean exhibits considerable multi-decadal variability
with time scales of about 50 to 100 years (see Chapter 3). This multi-
decadal variability appears to be a robust feature of the surface
climate in the Atlantic region, as shown by tree ring reconstructions
for the last few centuries (e.g., Mann et al., 1998). Atlantic multi-
decadal variability has a unique spatial pattern in the SST anomaly
field, with opposite changes in the North and South Atlantic (e.g.,
Mestas-Nunez and Enfield, 1999; Latif et al., 2004), and this dipole
pattern has been shown to be significantly correlated with decadal
changes in Sahelian rainfall (Folland et al., 1986). Decadal
variations in hurricane activity have also been linked to the multi-
decadal SST variability in the Atlantic (Goldenberg et al., 2001).
Atmosphere-Ocean General Circulation Models simulate Atlantic multi-
decadal variability (e.g., Delworth et al., 1993; Latif, 1998 and
references therein; Knight et al., 2005), and the simulated space-time
structure is consistent with that observed (Delworth and Mann, 2000).
The multi-decadal variability simulated by the AOGCMs originates from
variations in the MOC (see Section 8.3). The mechanisms, however, that
control the variations in the MOC are fairly different across the
ensemble of AOGCMs. In most AOGCMs, the variability can be understood
as a damped oceanic eigenmode that is stochastically excited by the
atmosphere. In a few other AOGCMs, however, coupled interactions
between the ocean and the atmosphere appear to be more important. The
relative roles of high- and low-latitude processes differ also from
model to model. The variations in the Atlantic SST associated with the
multi-decadal variability appear to be predictable a few decades
ahead, which has been shown by potential (diagnostic) and classical
(prognostic) predictability studies. Atmospheric quantities do not
exhibit predictability at decadal time scales in these studies, which
supports the picture of stochastically forced variability.'

http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch8s8-4-6.html

'Generally, the simulated late-20th century Atlantic MOC shows a
spread ranging from a weak MOC of about 12 Sv to over 20 Sv (Figure
10.15; Schmittner et al., 2005). When forced with the SRES A1B
scenario, the models show a reduction in the MOC of up to 50% or more,
but in one model, the changes are not distinguishable from the
simulated natural variability. The reduction in the MOC proceeds on
the time scale of the simulated warming because it is a direct
response to the increase in buoyancy at the ocean surface. A positive
North Atlantic Oscillation (NAO) trend might delay this response by a
few decades but not prevent it (Delworth and Dixon, 2000). Such a
weakening of the MOC in future climate causes reduced sea surface
temperature (SST) and salinity in the region of the Gulf Stream and
North Atlantic Current (Dai et al., 2005). This can produce a decrease
in northward heat transport south of 60°N, but increased northward
heat transport north of 60°N (A. Hu et al., 2004). No model shows an
increase in the MOC in response to the increase in greenhouse gases,
and no model simulates an abrupt shut-down of the MOC within the 21st
century. One study suggests that inherent low-frequency variability in
the Atlantic region, the Atlantic Multidecadal Oscillation, may
produce a natural weakening of the MOC over the next few decades that
could further accentuate the decrease due to anthropogenic climate
change (Knight et al., 2005; see Section 8.4.6).

In some of the older models (e.g., Dixon et al., 1999), increased high-
latitude precipitation dominates over increased high-latitude warming
in causing the weakening, while in others (e.g., Mikolajewicz and
Voss, 2000), the opposite is found. In a recent model intercomparison,
Gregory et al. (2005) find that for all 11 models analysed, the MOC
reduction is caused more by changes in surface heat flux than changes
in surface freshwater flux. In addition, simulations using models of
varying complexity (Stocker et al., 1992b; Saenko et al., 2003; Weaver
et al., 2003) show that freshening or warming in the Southern Ocean
acts to increase or stabilise the Atlantic MOC. This is likely a
consequence of the complex coupling of Southern Ocean processes with
North Atlantic Deep Water production.'

http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-3-4.html

Please note also the discussion on abrupt changes.

On Apr 21, 10:56 am, "David B. Benson" <dben...@eecs.wsu.edu> wrote:
> On Apr 19, 7:04 pm, Robert I Ellison <rob...@robertellison.com.au>
> wrote:> The formula you use is ...
>

[Per Edman]

It is precisely because of properly methodological, referencing and referenced articles in peer reviewed publications, that anyone expect you or anyone else to take anthropogenic climate change seriously, Robert, and yet you fail to do so. 

 / Per

--
/ Per

[David B. Benson]

On Apr 21, 1:50 am, Robert I Ellison <rob...@robertellison.com.au>
wrote:
> ...

> It is pseudo science that somehow links Arrhenius and the Atlantic
> Multidecadal Oscillation.

Fairly straightforward application of standard
scientific methods: Arrhenius explains almost
all of the variance and AMO explains almost all the rest, parly
because it is linked to MOC rate and so
a decent index of internal variability. {And yes,
I've read the papers, so you needn't bother to
quote those.)

> Expecting me to take it seriously would

> require a proper methodology ...
That it has.

>Let me know when you publish it.

Shan't bother. It is intended to inform those
still learning about climate using a simple an
approximation to the known physics as may be.
It is only intended to explicate the last 13
decades plus the coming one, not as a full
description of all of climate; it lacks a deep
ocean and a cryosphere, for starters. Neither
matter over such a short time interval.

Anyway, thanks for the attempt to read it and
discovering the missing right parenthsis in

AE(d) = k(lnCO2(d-1) - lnCO2(1870s)) - GTA(1880s)

which no previous commenter had noticed.

[Robert I Ellison]

I don't believe this at all. There are thousands of publications that
address climate variability from the perspective of everything from
dynamical systems, clouds, ocean states and cosmic rays. A few are
listed below. Where indeed are the dozens of better known sceptics in
this list of 5? There is climate change, obvious to everyone but Dr.
Ferenc Miskolczi, but how much is natural variability and how much
anthropogenic is the $64 question. How much, for instance, is clouds
(and why does cloud cover incresase and decrease) and how much is
greenhouse gases?

There is a lot of complexity in scientific opinion about a very
complex subject. For instance the Swanson et al 2009 paper 'Has the
climate recently shifted?' (see realclimate 'much ado about natural
variation' for a link and an explanation). Swanson, not a notorious
sceptic, suggests that the abrupt changes in 1976/1977 and 1998/2001
are dynamical responses not associated with anthropogenic climate
change. The residual warming Swanson links to CO2 is about half of
what is commonly quoted. I don't believe that either. Can we
conceptually have both a complex and dynamical system (abrupt change)
and a progressive evolution of climate?

This is a pointless Procrustean exercise. It is intended to replace
the need to think logically and in depth - to reinforce groupthink.
'We are many and you are few'. The saddest part is that the latter is
not true either - not that the majority view is any guarantee of
veracity. As Voltaire said - it's unlikely that even one person will
apprehend the truth let alone the majority.

NAS 2002, Abrupt climate change: inevitable surprises, NAP

Ghil, M., and E. Simonnet, 2007: Nonlinear Climate Theory, Cambridge
Univ. Press, Cam-
bridge, UK/London/New York

A UNIFIED MODELING APPROACH TO CLIMATE SYSTEM PREDICTION
by James Hurrell, Gerald A. Meehl, Davi d Bader, Thomas L. Delworth ,
Ben Kirtman, and Bruce Wielicki, BAMA Cec. 2009

Irreducible imprecision in atmospheric and oceanic simulations
James C. McWilliams, PNAS April 4, 2007 (received for review March 1,
2007)

Kunkel, M. and Pierce, J. (2006), The Influence of ENSO and PDO on
Idaho's Snowpack,
American Geophysical Union, Fall Meeting 2006, abstract #GC41A-1047

Mann, M., Bradley, R. and Hughes, M., (2000), Long-term variability in
the ENSO and
associated teleconnections. In ENSO: Multiscale Variability and Global
and Regional Impacts,
edited by H. F. Diaz and V. Markgraf, pp. 357-412, Cambridge Univ.
Press, New York.

Mantua, N., Hare, S. Zhang, Y. Wallace, J. and Francis, R. (1997), A
Pacific decadal climate
oscillation with impacts on salmon, Bulletin of the American
Meteorological Society, Vol. 78,
pp 1069-1079.

McLean, J. D., C. R. de Freitas, and R. M. Carter (2009), Influence of
the Southern Oscillation
on tropospheric temperature, J. Geophys. Res., 114, D14104, doi:
10.1029/2008JD011637.

Mestas-Nuñez, A and Miller, A (2006), Interdecadal variability and
climate change in the
eastern tropical Pacific: A review, Progress in Oceanography 69 (2006)
267–284

Pallé, E., P. R. Goode, and P. Montañés-Rodríguez (2009), Interannual
variations in Earth's
reflectance 1999–2007, J. Geophys. Res., 114, D00D03, doi:
10.1029/2008JD010734.

Svensmark, H., Bondo, T. and Svensmark, J. (2009), Cosmic ray
decreases affect atmospheric
aerosols and clouds, Geophys. Res. Lett., doi:10.1029/2009GL038429, in
press. (Climate
Research News)

Swanson, K.L., and A. A. Tsonis (2009), Has the climate recently
shifted?, Geophys. Res.
Lett., 36, L06711, doi:10.1029/2008GL037022.

Verdon, D. and Franks, S. (2006), Long-term behaviour of ENSO:
Interactions with the PDO
over the past 400 years inferred from paleoclimate records,
Geophysical Research Letters 33:
10.1029/2005GL025052.

Wang, L., Chen, W. and Huang R. (2008), Interdecadal modulation of PDO
on the impact of
ENSO on the east Asian winter monsoon, Geophys. Res. Lett., 35,
L20702,
doi:10.1029/2008GL035287.

Woodward, F., Lomas, M. and Quaife, T. (2008), Global responses of
terrestrial productivity
to contemporary climatic oscillations, Phil Trans R Soc B 2008 363:
2779-2785.

Yu, B. and Zwiers, F. (2007), The impact of combined ENSO and PDO on
the PNA climate: a
1,000-year climate modeling study, Climate Dynamics, Volume 29,
Numbers 7-8 / December,
2007

Clement, A., Burgmen, R. and Norris JR, (2009) Observational and model
evidence for
positive low-level cloud feedback, Science. 2009 Jul 24;325(5939):376.


On Apr 21, 6:46 pm, Erik Svensson <e...@chem.gu.se> wrote:
> The SVT has made a follow-up study on the scientific literature:http://uppsalainitiativet.blogspot.com/2010/04/swedish-television-goe...

> For more options, visit this group athttp://groups.google.com/group/globalchange- Hide quoted text -
>
> - Show quoted text -

[Robert I Ellison]

Is quoting this an example of not taking climate change
seriously???

'Large, abrupt climate changes have repeatedly affected much or all of
the earth, locally reaching as much as 10°C change in 10 years.
Available evidence suggests that abrupt climate changes are not only
possible but likely in the future, potentially with large impacts on
ecosystems and societies.

This report is an attempt to describe what is known about abrupt
climate changes and their impacts, based on paleoclimate proxies,
historical observations, and modeling. The report does not focus on
large, abrupt causes—nuclear wars or giant meteorite impacts—but
rather on the surprising new findings that abrupt climate change can
occur when gradual causes push the earth system across a threshold.
Just as the slowly increasing pressure of a finger eventually flips a
switch and turns on a light, the slow effects of drifting continents
or wobbling orbits or changing atmospheric composition may “switch”
the climate to a new state. And, just as a moving hand is more likely
than a stationary one to encounter and flip a switch, faster earth-
system changes—whether natural or human-caused—are likely to increase
the probability of encountering a threshold that triggers a still
faster climate shift.

We do not yet understand abrupt climate changes well enough to predict
them.'

http://www.nap.edu/openbook.php?record_id=10136&page=R5

Or the following.

‘Researchers first became intrigued by abrupt climate change when they
discovered striking evidence of large, abrupt, and widespread changes
preserved in paleoclimatic archives. Interpretation of such proxy
records of climate - for example, using tree rings to judge occurrence
of droughts or gas bubbles in ice cores to study the atmosphere at the
time the bubbles were trapped -is a well-established science that has
grown much in recent years. This chapter summarizes techniques for
studying paleoclimate and highlights research results. The chapter
concludes with examples of modern climate change and techniques for
observing it. Modern climate records include abrupt changes that are
smaller and briefer than in paleoclimate records but show that abrupt
climate change is not restricted to the distant past.’

US National Academy of Science (2002), Committee on Abrupt Climate
Changes, 'Abrupt Climate Change: Inevitable Surprises' NAP – p19

I referenced McWilliams on climate models.

'Sensitive dependence and structural instability are humbling twin
properties for chaotic dynamical systems, indicating limits about
which kinds of questions are theoretically answerable. They echo other
famous limitations on scientist’s expectations, namely the
undecidability of some propositions within axiomatic mathematical
systems (Godel’s theorem) and the uncomputability of some algorithms
due to excessive size of the calculation (see ref. 26).'

James C. McWilliams PNAS, 2007 'Irreducible imprecision in atmospheric
and oceanic simulations' NAP vol. 104 no. 21 8709–8713

I don't know how much clearer 'the science' can get - but unless
people start understanding abrupt change in the climate system the
'inevitable surprises' are going to continue to undermine rational
emmissions control. I am not the problem here. Eric is the problem
with a dogmatic and rather silly insistence of Holocene climate
stability, David is the problem with a confident, unsupported and
misguided insistance that the conditions for abrupt change no longer
hold, you are the problem because you have no appreciation of
scientific uncertainty, the limits of knowledge or the value of
scientific scepticism. You merely insist that I don't take climate
change seriously because of some unspecified bits of properly
formulated science - hardly a conceptually dense
proposition.

We need to move on but cannot. I was wondering if step by step
education of activists might be the way to permeate the zeitgeist with
an abrupt climate change meme. It does seem to be righter than the
stable climate idea and is a sceptic standard - albeit with a
different risk assessment than that of US National Academy of Science
quoted above. So it is not really a difficult concept if the sceptics
get it. I don't understand the resistance to this idea at all - other
than with vague notions of cognitive dissonance - but it is resistance
that is not well founded.

> For more options, visit this group athttp://groups.google.com/group/globalchange- Hide quoted text -
>
> - Show quoted text -

[Magnus Westerstrand]

The question was not about variability neither of Svensmark.

2010/4/22 Robert I Ellison <rob...@robertellison.com.au>

[Eric Swanson]

Robert,

Since you steadfastly refuse to discuss the issues I raised, I think
you should not refer to me as "the problem". I certainly recognize
the facts about abrupt changes in climate as found in the paleo data.
However, these changes, such as the Younger Dryas event, while
interesting, have no direct bearing on the present situation, since
the cause of the YD event no longer exists. Your reference to the NAS
report clearly points this out, if you would care to read Chapter 3.

Also, the abrupt changes discussed are not the result of chaos within
the atmosphere/ocean climate system, but other ituations. Since they
were not, you must not use them as examples of potential abrupt
changes which we may presently face. However, the mechanism within
the climate system which resulted in the YD cooling appears to be the
Thermohaline Circulation, which can be a cause of future abrupt
changes, but thru other forcings, such as the slow freshening of the
surface waters of the Nordic and Labrador Seas.

But, you don't appear interested in that problem, even though it was
discussed in the NAS book you linked to. Curious, isn't it? You
claim to be worried about abrupt climate change, yet are ignoring the
most likely path by which such might happen. Skepticism doesn't allow
one to ignore the data, which is what the denialist tend to do.

One wonders why it is that you are so worked up and yet remain so
blind. Haven't you read Chapter 4 of the NAS report?

http://www.nap.edu/openbook.php?record_id=10136&page=107

What sort of abrupt changes are you worried about?

E. S.
-----------------------------
On Apr 21, 11:01 pm, Robert I Ellison <rob...@robertellison.com.au>
wrote:

> I don't know how much clearer 'the science' can get - but unless
> people start understanding abrupt change in the climate system the
> 'inevitable surprises' are going to continue to undermine rational
> emmissions control.  I am not the problem here. Eric is the problem
> with a dogmatic and rather silly insistence of Holocene climate
> stability, David is the problem with a confident, unsupported and
> misguided insistance that the conditions for abrupt change no longer
> hold, you are the problem because you have no appreciation of
> scientific uncertainty, the limits of knowledge or the value of
> scientific scepticism.  You merely insist that I don't take climate
> change seriously because of some unspecified bits of properly
> formulated science - hardly a conceptually dense
> proposition.
>
> We need to move on but cannot.  I was wondering if step by step
> education of activists might be the way to permeate the zeitgeist with
> an abrupt climate change meme.  It does seem to be righter than the
> stable climate idea and is a sceptic standard - albeit with a
> different risk assessment than that of US National Academy of Science
> quoted above.  So it is not really a difficult concept if the sceptics
> get it.  I don't understand the resistance to this idea at all - other
> than with vague notions of cognitive dissonance - but it is resistance
> that is not well founded.
>

[Robert I Ellison]

The changes are unpredictable - and THC is one of the many factors
potentially involved - see chapter 3. Indeed, according to Chapter 3
of the NAS report a major problem with the THC theory is that it would
result in a localised cooling rather than the more generalised cooling
the data suggests.

'As discussed in Chapter 2, the Younger Dryas is the most studied
example of an abrupt change and provides insights about possible
mechanisms. In many ways the Younger Dryas serves as a defining event
that embodies the notion of abrupt climate change. Heinrich and
Dansgaard/Oeschger events are generally thought to be governed by
physical laws that are closely related to those involved in the
Younger Dryas; indeed, many consider the Younger Dryas to be just an
unusually big Heinrich or Dansgaard/Oeschger event. However, there are
potentially many types of abrupt change, as described in Chapter 2, so
we need to consider the full array of possible processes, rather than
only those currently in favor for explaining the Younger Dryas and
Dansgaard/Oeschger events.'

'These examples suggest that abrupt climate change can occur in (at
least) three fundamentally different ways:

Abrupt climate change can be the response to a rapidly varying
external parameter or forcing. If one views only the atmosphere-ocean
system, massive sudden discharges of freshwater from disintegrating
ice sheets on land would be an example of a sudden external influence.
Nonlinearity in the atmosphere-ocean system is not a prerequisite for
such behavior, whose time scale is dictated essentially by that of the
forcing.

Slow changes in forcing can induce the crossing of a threshold and
result in the transition to a second equilibrium of the system. The
evolution of such a change would be governed by the system dynamics
rather than by the external time scale of the slow change. In
considering the whole earth system rather than just the oceans and
atmosphere, massive discharges of freshwater from disintegrating ice
sheets would be a result of threshold-crossing. Slow melting at the
end of the last ice age produced ice-marginal lakes. When the ice
margin reached a particular location, such as the path of a former
river that the ice had dammed, a threshold was crossed, the ice dam
broke, and the water was released rapidly (Broecker et al., 1988).

Regime transitions can occur spontaneously in a chaotic system. In
this case, external triggers for transitions are not required, so a
series of regime changes could continue indefinitely or until slow
changes in external forcing or system dynamics removed the chaotic
behavior.'

You are looking at the big changes exclusively. It is the 'smaller
and less persistent' abrupt changes that has political implications
which you are continuing to not understand. You simply continue to
call me a 'denialist' ignoring the data. Forget global warming. If
unpredictable abrupt changes leads to a lack of warming or even a
cooling - there will never be a case in the mind of the general public
for reducing CO2. This may already be the case.

From my perspective - it is the result of otherwise well meaning and
intelligent people making simple connections and then assuming that
this was the entire explanation for a horrendously complex system on
which we have the most partial and conflicting science imaginable.
There are so many examples of scientific hubris in history that a
whole school of philosophy of science arose to warn us against this.

I don't think I'm blind - I think I have one eye in a world of the
blind. Maybe I flatter myself.

> For more options, visit this group athttp://groups.google.com/group/globalchange- Hide quoted text -
>
> - Show quoted text -