Dear Eric,
There is no need to be rude. I keep trying to find a way to
communicate a difficult concept in modern physics involving complex
systems as it relates to climate.
‘The climate system is particularly challenging since it is known that
components in the system are inherently chaotic; there are feedbacks
that could potentially switch sign, and there are central processes
that affect the system in a complicated, non-linear manner. These
complex, chaotic, non-linear dynamics are an inherent aspect of the
climate system.’ (IPCC TAR s14.2.2.1 -
http://www.ipcc.ch/ipccreports/tar/wg1/504.htm)
‘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.’ (Abrupt Climate
Change: Inevitable Surprises, 2002, NAP, p19 -
http://books.nap.edu/openbook.php?record_id=10136&page=19).
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.
The methodology has nothing at all to do with correlation or
causality. 'First we construct a network from four major climate
indices. The network approach to complex systems is a rapidly
developing methodology, which has proven to be useful in analyzing
such systems’ behavior [Albert and Barabasi, 2002; Strogatz, 2001]. In
this approach, a complex system is presented as a set of connected
nodes. The collective behavior of all the nodes and links (the
topology of the network) describes the dynamics of the system and
offers new ways to investigate its properties. The indices represent
the Pacific Decadal Oscillation (PDO), the North Atlantic Oscillation
(NAO), the El Niño/Southern Oscillation (ENSO), and the North Pacific
Oscillation (NPO) [Barnston and Livezey, 1987; Hurrell, 1995; Mantua
et al., 1997; Trenberth and Hurrell, 1994]. These indices represent
regional but dominant modes of climate variability, with time scales
ranging from months to decades. NAO and NPO are the leading modes of
surface pressure variability in northern Atlantic and Pacific Oceans,
respectively, the PDO is the leading mode of SST variability in the
northern Pacific and ENSO is a major signal in the tropics. Together
these four modes capture the essence of climate variability in the
northern hemisphere. Each of these modes involves different mechanisms
over different geographical regions. Thus, we treat them as nonlinear
sub-systems of the grand climate system exhibiting complex dynamics.'
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.
The SOI is sharply down and negative - indicating a return to La Nina
in the SH fall. This will lead to sharply lower global temps and
proportionately greater SH falls. The SAM index is positive but the 1
year tendency is to lower values. The SAM decadal tendency is to
negative values and sharply cooler SH conditions. The PDO is negative
of course and this is a decadal variation that is related to ENSO
frequency and duration - more frequent and intense La Nina in the
negative mode. This contributed to the lack of global warming over the
last decade which may intensify over the next decade or two.
ENSO and PDO have large impacts on global temperature because they
involve interactions between the deep ocean and the surface. More
cold upwelling results in cooler temperatures. More upwelling happens
when the oceans cool a little - perhaps as a result of cloud changes -
I refer you to the Project Earthshine site for a discussion of Earth
albedo changes. ENSO is also related to the Antarctic Polar Vortex.
Stratospheric ozone over the poles warms and cools as a result of
variation in solar UV in turn affecting the strength of the polar
vortex and thus surface flows along Antarctic Peninsula to the western
coast of South America. This in turn influences the thermal evolution
of the Humboldt Current and ENSO. Part of a complex web of
interacting global systems.
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.
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.
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.
Cheers
Robbo
On Jan 8, 9:54 am, Eric Swanson <[email protected]> wrote:
> On Jan 6, 10:50 pm, Robbo <[email protected]> wrote:
>
> > I was looking for a source for heat pollution - it seems to be just
> > another global apocalypse scenario - but do take everything on the
> > human knowledge site with a bucket of salt. Lucky we only have to
> > wait to 2012 for the end of the universe (LOL).
>
> > There is a new theory of climate that is a little more serious
> > -http://www.nosams.whoi.edu/PDFs/papers/tsonis-grl_newtheoryforclimate...
> > - it goes beyond the simple physics of gases and radiation to the
> > modern physics of complex systems. It views climate on decadal
> > timescales as an emergent property of complex and dynamic Earth
> > systems. There are all sorts of future possibilities - including
> > extremes. The ultimate 'strange attractors' seem to be states +/- 10
> > degrees C but being definitive beyond next month seems theoretically
> > impossible. Correlation certainly won't work as there is no simple
> > cause and effect.
>
> > Chaos theory explains why it hasn't warmed in the past decade. Thus
> > is the battle lost and it may take another generation or 2 to take any
> > action...
>
> > I am, at any rate, missing the point of science that needs to be
> > definitive and have scary answers. This is particularly the case
> > where science is synthesis rather than hypothesis and experiment.
>
> Robo guy, posting such long winded repeats of earlier rants is not
> likely to endear you with the moderators. Your fixation on bhe papers
> by Tsonis just shows your lack of understanding. The various indices
> which Tsonis et al. use don't cause anything, they just capture the
> variation in the weather patterns. There is no reason to assume that
> they are the only forces acting on the climate system, indeed we know
> of several external forcings which are time variant. Without
> understanding causality, it's a fools game to jump into prediction.
> Chaos "theory" doesn't explain why there are correlations between the
> indices.
>
> For example, tell us what you think the NAO means? Let's also hear
> your discussion of the THC process and potential for variation.
>
> E. S.
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