Robbo is wrong again! How else can I say it?
On Jan 9, 3:53 pm, Robbo <[email protected]> wrote:
> If there are serious problems with the Tsonis methodology that are
> addressed in the peer reviewed literature - I am not aware of it and
> you have not enlightened me. For one thing - Tsonis et al use NH
> winter averages in an 11 year window - not an 11 year moving
> average.
>From Tsonis et al. regarding Eqn 1:
"Here t denotes the time in the middle of a sliding window of
width Dt... Figure 1a shows the distance as a function of time for
a window length of Dt = 11 years"
A sliding window is the same as a centered moving average...
> Let's have a look at SAM. The SAM index is on based on sea level
> pressure (SLP)at a number of sub-Antactic sites. SLP is a function of
> downwelling which in turn is dependent on UV warming of ozone in the
> stratosphere. Higher temps produce less downwelling air feeding into
> the polar vortex and thus lower SLP. So the SAM index captures some
> pretty basic processes. The storm tracks in the SH are the result of
> complex interactions of equatorial and sub-Antartic SLP.
>
> But these are subsystems - of which there are legion - of what Tsonis
> calls the grand climate system. Dynamical systems theory as applied
> to climate is not concerned with forcings as such. Forcings of all
> sorts are small changes in initial conditions that trigger large
> changes in complex systems. It is not simple cause and effect - which
> does not apply in the grand complex and dynamic climate system. We
> are concerned with the behaviour of the system. Complex and dynamic
> systems behave in certain ways - so if it is demonstrated that climate
> behaves in the same ways at interannual to decadal and beyond scales
> it provides a new way of analysing climate.
Of course, the climate system exhibits chaotic behavior and may
exhibit periodic oscillatory behavior. But, at the risk of breaking
thru to your inner thoughts, that fact does not mean that changes in
climate can be predicted simply by looking at the various indices as
Tsonis et al. claim. Since there are other processes involved beyond
whatever dynamical system responses might obtain, looking at those
indices alone without considering the other forcings will provide
little useful information, since the oscillations are unlikely to be
periodic.
> 'Dynamical systems theory and chaos theory deal with the long-term
> qualitative behavior of dynamical systems. Here, the focus is not on
> finding precise solutions to the equations defining the dynamical
> system (which is often hopeless), but rather to answer questions like
> "Will the system settle down to a steady state in the long term, and
> if so, what are the possible steady states?", or "Does the long-term
> behavior of the system depend on its initial condition?"'
Neither question can be answered, since we can't start the real system
with a definitive set of initial conditions and assessing such
questions using data from the continually changing Earth is not likely
to be successful either. One can do experiments such as these with
computer models, but how can one be sure the results apply to the real
Earth? Or, if you agree the models are an accurate representation of
the Earth's climate, wouldn't you also accept the projections of
future climate based on such models?
> In this perspective, the current lack of warming is emergent behaviour
> of climate as a dynamical complex system. It is a steady state that
> tends to persist - qualitative behaviour - for a couple of decades
> until perturbed by more small changes in initial conditions (or
> climate forcings as they are known).
You assert without proof that the current lack of warming is the
result of internal system dynamics. Until you can provide such proof,
you are blowing smoke...
>...I understand that people are
> reluctant to accept a conclusion that is based on some fairly esoteric
> science. Many activists would want to label me a 'denialist' and send
> me to the salt mines. But it provides at least a metatheory for lack
> of warming over the last decade - if the details are still very
> unclear. And please - who was it in the leaked emails who said that
> the lack of explanation for non warming was a
> travesty?
That quote was taken from an e-mail by Trenberth and most reports by
the denialist camp have cherry picked the statement by taking it out
of context. Here's a link to the report with the original quote,
which I hope you will read.
http://www.cgd.ucar.edu/cas/Trenberth/trenberth.papers/EnergyDiagnostics09final.pdf
BTW, I notice that there was no comment from you on the link to
today's NYT story. I guess you don't care about the ENSO.
> Once the application of dynamical systems theory to climate is
> understood it provides a new way of looking at climate that integrates
> both forcings and dynamic Earth system responses.
That's the problem, not the solution.
E. S.
---
--
You received this message because you are subscribed to the Google Groups
Global Change ("globalchange") newsgroup. Global Change is a public, moderated
venue for discussion of science, technology, economics and policy dimensions of
global environmental change.
Posts will be admitted to the list if and only if any moderator finds the
submission to be constructive and/or interesting, on topic, and not
gratuitously rude.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/globalchange
