http://pespmc1.vub.ac.be/ASC/Dissip_struc.html

DISSIPATIVE STRUCTURE
A system that exits far from thermodynamic equilibrium (see
thermodynamics), hence efficiently dissipates the heat generated to
sustain it, and has the capacity of changing to higher levels of
orderliness (see self-organization). According to Prigogine, systems
contain subsystems that continuously fluctuate. At times a single
fluctuation or a combination of them may become so magnified by
possible feedback, that it shatters the preexisting organization. At
such revolutionary moments or "bifurcation points", it is impossible
to determine in advance whether the system will disintegrate into
"chaos" or leap to a new, more differentiated, higher level of
"order". The latter case defines dissipative structures so termed
because they need more energy to sustain them than the simpler
structures they replace and are limited in growth by the amount of
heat they are able to disperse. (Krippendorff)

http://staff.science.nus.edu.sg/~par...c3/node49.html

Dissipative Structures
In this chapter we take our first detailed look at "truly" complex
systems: Systems that large and out-of-equilibrium. Unfortunately,
unlike the case for equilibrium systems, there is no well-developed
formalism for studying such systems. Nevertheless one can identify
some principles and resort to phenomenological equations or computer
simulations of models to test ideas.

http://staff.science.nus.edu.sg/~par...c3/node51.html

Vortices
The first example of a dissipative structure is a vortex, such as that
which forms when water drains through the plughole in a bathtub or
sink. The smooth flow of water far away from the plughole changes to
fast swirling motion that leads to the formation of a structured
object, the vortex. Larger examples of vortices are tornadoes that are
common in the USA (and recently starred in the movie Twister!): When
cold air from Canada collides on the continent with warm air from the
Gulf of Mexico, intense thunderstorms result. All air-masses have a
certain amount of rotational motion to begin with. When such air
converges into the updraft of an intense thunderstorm, the rotational
motion speeds up because of the conservation of angular momentum.
(Recall how a skater increases her rate of spin by drawing in her
arms). The vortex is an example of a time-dependent complex system. It
is difficult to characterize in terms of a few parameters as in
equilibrium systems studied earlier. In fact notice that the formation
of the vortex breaks the homogeneity, or symmetry, of the non-moving
water/air-mass. Thus this is our first example of greater macroscopic
structure or dynamical order, in a non-equilibrium system.

http://www.prototista.org/E-Zine/Ori...nceoforder.htm

On the Origins of Order:

Spontaneous emergence of order
& fast changes (bifurcations)

We are coming to understand that order arises spontaneously in
networks. That is, order appears in non-linear, far-from-equilibrium
dissipative structures by a process of self-organization, without an
organizing force operating from outside the system (like natural
selection), or an internal organizer (like DNA as a set of
instructions) or a fifth force like the vital force, or Sheldrake's
morphic fields) to direct or program the operation. The key to
understanding why lies in understanding these concepts: far from
equilibrium, non-linearity, feedback, dissipative structures,
emergence, autopoiesis, bifurcation and attractor states.

These ideas are central to understanding self-organization in Capra's
book. As he writes:

"The [new] models of self-organizing systems share certain key
characteristics, which are the main ingredients of the emerging
unified theory of living systems to be discussed in this
book…Summarizing those three characteristics of self-organizing
systems, we can say that self-organization is the spontaneous
emergence of new structures and new forms of behavior in open systems
far from equilibrium, characterized by internal feedback loops and
described mathematically by non-linear equations (85)".

Furthermore, thanks to the sciences of Complexity, we are finally
coming to intellectually understand what we have intuitively and
experientially known for millennia: rapid, unexpected jumps and
changes seen in the phenomena studied by various fields of science are
all examples explained by the same principles. Namely, they are
bifurcations to new states of order resulting from instabilities in
far-from-equilibrium, non-linear systems. None of these phenomena can
be understood, let alone explained, using the linear mechanistic
models described in most college texts.

The wide range of phenomena demonstrates the interdisciplinary nature
of Complexity. Examples include:

the spontaneous emergence of order in the Benard instability (related
to tornadoes and hurricanes);

http://www.spontaneousorder.net/humaneco4.html

AUTOCATAKINETICS: A THEORY OF EMBEDDED CIRCLES


Identity Through Flow

Symmetry Breaking And Symmetry Making: Autocatakinesis,
And The Generalized Metabolism Of Dynamic Flow Structures

....Living systems from bacteria to cultural systems, as
self-organizing, or spontaneously ordered systems, are defined by
dynamic order‹their identity is constituted through the incessant flux
of their components which are continuously being replaced from raw
materials in their environments, and expelled in a more dissipated
form. Persistence (the form of the thing) at one level (the "macro"
level) is constituted by change at the component level (the "micro"
level). In more technical terms, living systems are autocatakinetic
systems while artifactual systems are not. The class of
autocatakinetic systems includes more than just living systems, and
this immediately suggests a connection between living and non-living
things that will be more apparent later on. Dust devils, hurricanes,
and tornadoes, for example, are all examples of autocatakinetic flow
structures whose identities are constituted in just this way‹by the
incessant flux of matter and energy pulled in from, and then excreted
or expelled back into, their environments in a more degraded or
dissipated form (see Figure 2).

Figure 2. A tornado is an example of an autocatakinetic system, a
dynamically ordered flow structure whose identity, in contrast to a
machine, or artifact, is constituted not by a set of particular
components typically occupying fixed positions with respect to each
other, but by the ordered relations maintained by the incessant flow
of its components. The dynamical order that defines the persistence of
an autocatakinetic system as an object at the macro level, is
maintained through constant change at the micro level. This incessant
flux of components can be thought of as a generalized metabolism by
which the system maintains itself by pulling environmental potentials
(or resources) into its autocatakinesis, which it returns in a more
dissipated form. All living things from bacteria to human cultural
systems as well as the planetary system as a whole, which maintains a
constant level of oxygen, for example, by this same generalized
process, are all members of the class of autocatakinetic systems.
Photo courtesy of the National Severe Storms Laboratory.

An autocatakinetic system is defined as one that
maintains its "self" as an entity constituted by, and empirically
traceable to, a set of nonlinear (circularly causal) relations through
the dissipation or breakdown of field (environmental) potentials (or
resources) in the continuous coordinated motion of its components
(from auto- "self" + cata- "down" + kinetic, "of the motion of
material bodies and the forces and energy associated therewith" from
kinein, "to cause to move")(Swenson, 1991a).


http://maps.unomaha.edu/Peake/3510/thunder.html

THUNDERSTORMS, LIGHTNING AND TORNADOES
....
TORNADO FORMATION
A strong thunderstorm provides the concentrated, persistent updraft
needed to launch a tornado and to prevent its low pressure core
from filling from above
-when the top of such a storm is viewed from a satellite it usually
displays a characteristic sequence of rising bubbles of cloud
material that overshoot the mean cloud top by two to four km
and then subside back into the cloud mass.
-bubbles are indicators of a strong updraft with a high degree
of organization in the storm
-for a tornado to be formed, however, the air in the updraft must
begin to rotate as well
-this can happen if the updraft concentrates the spin contained
in the horizontal winds in the troposphere.

Not just any winds will do
-they must be strongly sheared vertically in both magnitude and
direction; the wind speed must increase with altitude and direction
must veer from southeast to west
-vertical shear in wind speed provides a source of rotation about
a horizontal axis
-as winds aloft are moving faster a paddlewheel effect
is set up
-shear in wind direction also provides a source of rotation
-especially effective as updraft begins

According to current models, a severe thunderstorm gives rise
to a tornado in two steps
1. first the entire thunderstorm updraft begins to rotate
-this spinning column of rising air 10 to 20 km in diameter
is called a mesocyclone
-rotation begins in the mid troposphere
2. Once rotation has begun at mid levels it builds down toward
the ground through a dynamic pipe effect
-along the rotating column the pressure field is now in balance with
the strongly curved wind field
-the inwardly directed force acting on air parcels as a result
of the reduced pressure at the center of the column is
countered by the outwardly directed centrifugal force resulting
from the parcel's rotation about the center.
-in such a condition of cyclostrophic balance the air can easily
move around and along the axis of the cyclone,but radial
motions toward or away from the axis are strongly suppressed
-almost all the air entering the column must come from
its lower end.
-it is like a vacuum cleaner hose except that instead of
being channeled by the wall of the hose the airflow in
the cyclone constrained by its own swirling motion.

The result is an intensification of the updraft and hence of the
converging
winds under the cyclone
-because of the shear in wind direction, the air converging into the
updraft has a component of spin about the center of the column
-as the air parcels distance from the center of rotation decreases
its velocity must also increase and it begins to spin faster
about the center
As air parcels converge into the base of the pipe they turn and
accelerate
upward
-this results in their being stretched vertically
-stretching narrows the diameter of the mesocyclone from two to
six km

Tilting, the dynamic pipe effect,convergence and vertical stretching
processes that feed on one another can eventually form a mesocyclone
that extends from about l km above the ground to near the top of the
thunderstorm at about l5 km.
-surface winds with speeds as high as 75 mph can blow over the large
region under the swirling column
-the rotation in the mesocyclone is still too diffuse and too
far aloft to generate truly intense surface winds

The generation of such winds comes in THE SECOND STEP by which a
severe
thunderstorm gives rise to a tornado; the formation of the actual
tornado core.
-for reasons that are not yet understood, a region of enhanced
convergence and stretching, no more than l km in diameter appears
to develop inside the mesocyclone, toward one side
-Doppler radar observations suggest that the intensification of
spin begins aloft, at altitudes of several km and then quickly
builds down toward the ground.
-over such a small area the rotational motion is strong enough
for the dynamic pipe effect to reach within several tens
of meters of the ground
-close to the ground, friction prevents the establishment of
a cyclostrophic balance by slowing the rotational motion

In response to the pressure gradient between the tornado core
and the surrounding atmosphere, air streams inward through a thin
layer near the ground.
-owing to inertia, the inflow actually overshoots its equilibrium
radius, conserving its angular momentum and picking up speed
as it approaches the center of the core before turning sharply
to spiral upward
-as a result the highest wind speeds are found in a small ring shaped
region at the base of the vortex.


BASIC CHARACTERISTICS

Average path is 25 km
-May 26, l9l7 in Ill and Ind 469 km path 7 hrs 20 min
April 3 and 4, l974 148 tornadoes 315 deaths
Winds up to 400 km per hour or as less as 65 km/hr
Speed 55-70 km per hour
Move generally from southwest to northeast
-most are about 100 yards in diameter or so
-most are on ground only for a few minutes



TORNADO DISTRIBUTION

Occur in England, France, Germany, Hungary, Italy, India, Russia,
Japan, Canada and Australia

In North America are about 600 per year

Rare on east and west coasts
-May most December east
Seasonal march of maximum frequency

Time of day in Great Plains 2/3 occur between 1 and 8 at night

Tornado maxima precedes hail max. by l month and Tstorm max by 2

On 9 Jul 2003 17:03:02 -0700, Melchizedek@USA.com (Psalm 110) wrote:

And did you find this all by yourself? You do realise that
there is nothing in this gibberish that amounts to proof.


>
>http://staff.science.nus.edu.sg/~par...c3/node51.html
>
>Vortices
>The first example of a dissipative structure is a vortex, such as that
>which forms when water drains through the plughole in a bathtub or
>sink. The smooth flow of water far away from the plughole changes to
>fast swirling motion that leads to the formation of a structured
>object, the vortex. Larger examples of vortices are tornadoes that are
>common in the USA (and recently starred in the movie Twister!): When
>cold air from Canada collides on the continent with warm air from the
>Gulf of Mexico, intense thunderstorms result.

What a load of BS. There is no requirement for clashing
airmasses. Two things are required for thunderstorm: instability and
lift. If you have those in the proper measure you can produce a
thunderstorm. Throw in deep layer shear and you have the potential for
organized long-lived deep convection: a supercell.

>All air-masses have a
>certain amount of rotational motion to begin with.

Airmasses can have some rotational motion, but not always. You
also have to have the right motion. Anti-cyclonic rotation exists but
is rather uncommon. Vorticity is a function of wind speed such that

w = del X V, where del is the del operator and V is the 3
dimensional wind speed.

>When such air
>converges into the updraft of an intense thunderstorm, the rotational
>motion speeds up because of the conservation of angular momentum.

More gibberish. They're talking about a number of different
processes at work and getting them confused. First of all, in the
absence of shear, you don't have streamwise vorticity, the component
of the horizontal vorticity parallel to the horizontal wind to be
tilted into the thunderstorm updraft to undergo stretching. What can
happen with things like landspouts is that the thunderstorm updraft
moves over an area of pre-existing vorticity that is then stretched
out. You don't even need a thunderstorm to do this.
In a strong shear environment, streamwise vorticity is
available in abundance and that can be tilted into the updraft of a
thunderstorm. The effect of this is not to produce a tornado, but
rather to produce a rotating updraft that tilts down shear. Rain
produced by the thunderstorm cannot fall back into the updraft choking
it off the way that pulse storms do, so these storms, so-called
supercells, are very long-lived.
Tornado's form through multiple mechanisms and cover a huge
spectrum of shapes and sizes. In tornadic supercells it is the complex
interactions between the rotating updraft and the rear flank
downdraft.
The simple fact is, that the type of weak tornado they are
talking about doesn't require anything to do with temperature to form.
Weak multicell storms will often produce chaotic outflow boundaries
with very complex interactions. Any rinky-dink thunderstorm passing
over this pre-existing vorticity will stretch it out.
If you want to make this kind of argument you're going to have
to show how GW will alter the basic parameters needed for the
development of deep convection: instability, lift and shear.