I think the evidence for climate shifts on decadal scales is evident
in science of all sorts. Global shifts in temperature, rainfall, the
'Great Pacific Climate Shift' of 1976/1977, the instrumental
temperature record. As indicated in the 2002 panel discussion of the
National Academy. Tsonis et al have the virtue (in peer reviewed
studies) of using numerical techniques to quantify. The numerical
technique was not concerned with cause and effect - or cross
correlation in the accepted sense - but in detecting patterns in
signals. A network methodology as in the quote I provided earlier.
Show me the papers disputing Tsonis - not simply your frankly silly
claim that because they didn't factor out ENSO and volcanos from ENSO
and other signals that the studies are invalidated.
I sure I don't have a clue what you mean by 'speeding up'. The
concept is that small changes in initial conditions triggers large
flucuation in climate which then oscillates about a new state for a
while. The oscillations tend to damp out (but not neccessarily)in
complex systems providing a signal of the next shift.
I link to the UNESCO site that provides ready access to indices that
are updated by thousands of scientists around the world. And you
simply accuse me of provising unjustified claims - a knee jerk no it
just ain't so. Show me the science damn it. Your claim that these
indices are not relevant because of global warming is unreflective
nonsense. Somehow ENSO and the like have no relevance for
understanding climate? Please.
You are just being foolish now.
On Jan 9, 12:28 pm, Eric Swanson <[email protected]> wrote:
> Robbo wrote:
> > Eric,
>
> > I am indeed a civil engineer with a masters in environmental science.
>
> I noticed that...
>
> > When you say correlation you are thinking in terms of cross
> > correlation of TSI with temperature for instance - a forcing with an
> > effect. In the Tsonis case the correlation is of the topological
> > 'distance' between indices. It is more like the autocorrelation
> > technique used by Dakos et al to examine abrupt climate change in the
> > past. Autocorrelation is used to discern a repeating pattern in a
> > signal.
>
> Yes, Tsonis uses correlation coefficient in defining their analysis.
> See the definition of their so-called "distance", d(t), defined using
> the cross-correlation coefficient, rho,i,j(t). But you previously
> wrote that they didn't use correlations. I assume that you now agree
> with me...
>
> > 'Slowing down as an early warning signal for abrupt climate change':
> > Vasilis Dakos, Marten Scheffer, Egbert H. van Nes, Victor Brovkin,
> > Vladimir Petoukhov, and Hermann Held
>
> > 14308–14312:PNAS:September 23, 2008:vol. 105:no. 38
>
> Isn't this a bit of a red herring? Aren't you shifting the discussion
> away from Tsonis, et al.??
> And old trick, I must say. BTW, the recent NH winter weather looks
> like things are speeding up..
>
> > You reject complex system dynamics but I quote the IPCC and the NAP as
> > well in support of the view of climate as a dynamic complex system on
> > all scales from ENSO to ice ages and beyond. But these are just words
> > and one needs something of an understanding of the background theory
> > to understand what these words mean in context. Chaos theory and
> > strange attractors are indeed central to concepts of abrupt and large
> > climate change.
>
> No, I don't reject such analysis. I just don't think the work of
> Tsonis et al. means as much as they (and you) would have us believe.
>
> > I don't say anything about the future in black and white terms - but
> > the indices I mentioned in response to your question have implications
> > for climate and weather. For instance, the SAM index and the NAO
> > index have implications for the tracks of storms spinning off the
> > polar vortices. The PDO is associated with multidecadal modulation of
> > ENSO - with obvious implications for climate.
>
> > There are a large number of ocean/climate indices -
> >http://ioc-goos-oopc.org/state_of_the_ocean/all/- these allow
> > qualitative judgements about regional rainfall and climate on
> > interrannual to multidecadal scales to be made without considering
> > solutions to the Navier-Stokes partial differential equations.
>
> But such indices do not provide meaningful projections of a changing
> climate, since the underlying forcings are changing as we know.
>
> > I guess you are the 31.07 year old software engineer known as E-dawg?
>
> Not, although I did work as a scientific programmer for several years
> after grad school.
>
> > I guess that your problem is not with the idea under discussion of
> > abrupt climate change - so much as what no warming for a decade or 2
> > will do with what's left of the public debate.
>
> The so-called debate has degenerated into little more than name
> calling on the part of the denialist. They (like you) offer little
> substantive discussion, while falling back on unfounded assertions and
> repeating unproven and often debunked claims.
>
> > Regardless of my views - there is no need to be rude and
> > aggressive.
>
> Well, I don't think I'm the one being aggressive as you have been the
> poster of several similar long winded comments praising Tsonis, et al.
> without considering the problems in their analysis.
>
> > Cheers
> > Robbo
>
> E. S.
> ---
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