Robbo,
With all due respect to you and your civil engineering experience, I
think you have missed my point.
Robbo wrote:
> The Tsonis et al theory of ocean/climate states
> http://www.nosams.whoi.edu/PDFs/papers/tsonis-grl_newtheoryforclimateshifts.pdf)
> confirms that climate on decadal timescales is an emergent property of
> complex and dynamic Earth systems. "You go from a cooling regime to a
> warming regime or a warming regime to a cooling regime. This way we
> were able to explain all the fluctuations in the global temperature
> trend in the past century," Anastasios Tsonis said.
>From which you conclude:
> The methodology has nothing at all to do with correlation or causality.
But, as Tsonis states:
"[5] Figure 1a shows the distance as a function of time for a window
length of Dt = 11 years, with tick marks corresponding to the year in
the middle of the window. The correlations (and thus distance values
for each year) were computed based on the annual-mean indices
constructed
by averaging the monthly indices over the period of November–March.
The dashed line parallel to the time axis in Figure 1a represents the
95% significance level associated with the null hypothesis that the
observed indices are sampled from a population of a 4-dimensional AR-1
process driven by a spatially (cross-index) correlated Gaussian noise;
the parameters of the AR-1 model and the covariance matrix of the
noise are derived from the full time series of the observed indices.
This test assumes that the variations of the distance with time seen
in Figure 1a are due to sampling associated with a finite-length (11-
yr) sliding window used to compute the local distance values.
Retaining overall cross-correlations in constructing the surrogates
makes this test very stringent. Nevertheless, we still find five times
(1910s, 1920s, 1930s, 1950s, and
1970s) when distance variations fall below the 95% significance level.
We therefore conclude that these features are not likely to be due to
sampling limitations but they represent statistically significant
synchronization events."
In other words, the "proof" of their technique is statistical
correlations. And, they use an 11 year moving average to define their
indices. Moving averages induce spurious "signals" into a time series
thru aliasing. I think that using a moving average thusly may
invalidate their results.
> The NAO is strongly negative and this may be a decadal variation
> leading to very much cooler conditions over the NH. The Bermuda-
> Labrador Basin Transport Index is near it's low point in the very
> limited record. A strong cooling - as is being seen in the current NH
> winter - may continue. It has happened in the past century - it is
> very possible that NH (particularly US, northerly regions of Europe
> and the Arctic) temperatures will fall strongly over the next decade
> or 2.
This does not answer my question. You asserting some future course
for the weather with no link to causality, with no mention of the
historical forcings. To me, such a claim is poor science.
Think of it this way. Build a time series of hourly temperature for
summer. Now, try and "predict" the next full year's temperatures
using Tsonis approach. Will you be able to come anywhere near the
temperatures in winter? Without a full understanding of the rest of
the yearly cycles, such as the yearly solar cycle, you can't come
close to reality. Even with several years of hourly data, you will
still find that such a prediction will miss reality quite a few
times.
> The indices are not indicative of any causal agency but do capture
> modes of climate variability and associated effects. It is like
> saying that the PDO and ENSO cause changes in decadal patterns of
> rainfall in Africa, Australia, Asia, the USA and South America. But
> the underlying cause is not PDO or ENSO but the dynamics of climate as
> a forced nonlinear oscillator expressing in part as the PDO and
> ENSO.
You are assuming that ALL the variation is captured by these indices
and that this variation is the result of the presumed internal
oscillators. The indices don't cause anything, they are just
indicators of the changes in what is measured. They are not
predictive, since they are not based on any changes which may be
occurring in the external forcing, such as solar variability, volcanic
eruptions, additions of greenhouse gases, etc. Tsonis et al. do not
even attempt to remove the external forcings from their indices before
concluding that they have a handle on the internal oscillations.
> Chaos theory confirms the reality of the risk of serious climate
> change (either warming or cooling) in response to greenhouse gas
> forcing. In the short term however (a decade or so), surface
> temperature may continue on the current trajectory of a lack of
> warming.
Again, you make a projection of the future climate based on an
assertion that chaos "theory" will provide a framework to make this
projection. At the moment, it's not clear what might be causing the
slow down in warming, from my limited understanding. It might turn
out that the increased emissions of sulfates and other forms of air
pollution in China and India may be the reason or it may also be that
there is a reduction in the THC in the North Atlantic as a result of
Global Warming. We know both are happening. Can your chaos theory
pick out these possible causes? I think not, since the process is
backward looking and ignores the various forcings.
> Most people always think they have the complete and unvarnished
> truth. The usual state of the human condition is more or less
> complete ignorance. Indeed the best definition of science I know of
> is that science is exploration at the boundary of human ignorance. It
> is a hard lesson learned time and time again.
Sounds reasonable to me. Try telling that to the religious
fundamentalists. So, what does that have to do with your continual
ranting about Tsonis et al.? You are acting like a troll, repeatedly
posting your latest world view for ego gratification or what ever
reasons. Perhaps you should take a bit more time to study the
atmospheric sciences before you start jumping up and down and shouting
"This is IT!!"
E. S.
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