Taylor–Couette Circulation

Earth’s atmospheric circulation is primarily driven by “solar heating” and the “Hadley system provides an example of a thermally direct circulation” according to Settled Science.

The major driving force of atmospheric circulation is solar heating, which on average is largest near the equator and smallest at the poles.

The atmospheric circulation transports energy polewards, thus reducing the resulting equator-to-pole temperature gradient.

The Hadley system provides an example of a thermally direct circulation.

The thermodynamic efficiency of the Hadley system, considered as a heat engine, has been relatively constant over the 1979~2010 period, averaging 2.6%.

The mechanisms by which this is accomplished differ in tropical and extratropical latitudes.

https://en.wikipedia.org/wiki/Hadley_cell#Mechanism

Atmospheric circulation is the large-scale movement of air, and is a means by which thermal energy is distributed on the surface of the Earth, together with the much slower (lagged) ocean circulation system.
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Latitudinal circulation occurs because incident solar radiation per unit area is highest at the heat equator, and decreases as the latitude increases, reaching minima at the poles.

It consists of two primary convection cells, the Hadley cell and the polar vortex, with the Hadley cell experiencing stronger convection due to the release of latent heat energy by condensation of water vapor at higher altitudes during cloud formation.

Longitudinal circulation, on the other hand, comes about because the ocean has a higher specific heat capacity than land (and also thermal conductivity, allowing the heat to penetrate further beneath the surface) and thereby absorbs and releases more heat, but the temperature changes less than land.
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Longitudinal circulation consists of two cells, the Walker circulation and El Niño / Southern Oscillation.

https://en.wikipedia.org/wiki/Convection#Atmospheric_circulation

However, there are a few issues with this “heat engine” view of atmospheric circulation.

Firstly, convection produces localised convection cells [aka Bénard cells].

Rayleigh–Bénard convection is a type of natural convection, occurring in a plane horizontal layer of fluid heated from below, in which the fluid develops a regular pattern of convection cells known as Bénard cells.

https://en.wikipedia.org/wiki/Rayleigh%E2%80%93B%C3%A9nard_convection

Secondly, strong atmospheric convection produces thunderstorms that are wedged between the walls of adjacent Bénard cells i.e. atmospheric convection is associated with localised phenomena.

Thunderstorms are known to occur in almost every region of the world, though they are rare in polar regions and infrequent at latitudes higher than 50° N and 50° S.
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Areas of the atmosphere where vertical motion is relatively strong are called cells, and when they carry air to the upper troposphere (the lowest layer of the atmosphere), they are called deep cells.

Thunderstorms develop when deep cells of moist convection become organized and merge, and then produce precipitation and ultimately lightning and thunder.

Upward motions can be initiated in a variety of ways in the atmosphere.

A common mechanism is by the heating of a land surface and the adjacent layers of air by sunlight.
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Isolated thunderstorms contain one or more convective cells in different stages of evolution.

Frequently, the downdrafts and associated outflows from a storm trigger new convective cells nearby, resulting in the formation of a multiple-cell thunderstorm.

Thunderstorms – E. Philip Krider – Encyclopædia Britannica
https://www.britannica.com/EBchecked/topic/594363/thunderstorm

Thirdly, Taylor–Couette Flow produces “roll-like vortices” which are “closely analogous to convection”.

These are in fact roll-like vortices in which the fluid circulates in alternate directions, as if around the surfaces of a stack of doughnuts.

Like Rayleigh–Benard convection, this is a symmetry-breaking process that creates a pattern of a well-defined size.

It isn’t too hard to see that this situation is closely analogous to convection, in which the same kind of symmetry-breaking structure (roll cells) is created.
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At a threshold rotation speed, the system becomes unstable so that roll vortices transport part of the inner fluid to the outer edge while a return flow replenishes the inner layer.

Not only is the instability of the same basic nature as that in convection, but the shape of the rolls is the same: roughly square, as wide as the gap between the inner and outer cylinders

Flow – Philip Ball – 2009 – Oxford University Press

In fact, the “roll-like vortices” of Hadley Cells [in cross section] appear to mirror the structure of Taylor–Couette Flow far more than they reflect the structure of Bénard Cells.

Igneous and Metamorphic Petrology – Supplemental Graphics
Prof. G. Nelson Eby – Environmental, Earth & Atmospheric Sciences
University of Massachusetts Lowell
http://faculty.uml.edu/nelson_eby/89.304/Material.htm

The El-Nino (ENSO) Phenomenon – Pierre Madl -2000
http://biophysics.sbg.ac.at/atmo/elnino.htm

https://en.wikipedia.org/wiki/Taylor%E2%80%93Couette_flow

Fourthly, the Earth’s “six major wind belts” emulate the “roll-like vortices” produced by Taylor–Couette Flow where the fluid “circulates in alternate directions”.

Global wind patterns: Winds are named by the direction from which they blow.

The globe is encircled by six major wind belts, three in each hemisphere.

https://en.wikipedia.org/wiki/Global_wind_patterns

But the British mathematician Geoffrey Taylor found in 1923 that, once the centrifugal force starts to overwhelm the damping effect of viscosity, patterns appear.

First, the column of fluid develops stripes.

These are in fact roll-like vortices in which the fluid circulates in alternate directions, as if around the surfaces of a stack of doughnuts.

Flow – Philip Ball – 2009 – Oxford University Press

However, because the Polar Easterlies are “weak and irregular” is it probably more accurate to state that the Earth has four major wind belts.

The polar easterlies (also Polar Hadley cells) are the dry, cold prevailing winds that blow from the high-pressure areas of the polar highs at the north and south poles towards low-pressure areas within the Westerlies at high latitudes.

Cold air subsides at the poles creating the high pressure, forcing an equatorward outflow of air; that outflow is then deflected westward by the Coriolis effect.

Unlike the westerlies in the middle latitudes, the polar easterlies are often weak and irregular.

http://en.wikipedia.org/wiki/Polar_easterlies

This is an important qualification because the Taylor–Couette Flow that forms around a sphere generates a “very robust” vortical structure with four bands when there is “axial flow”.

The addition of an axial flow in the annulus or a radial flow through porous cylinders alters the critical Taylor number as well as the wavelength and structure of the vortices.

Likewise, the flow is altered by oscillating the inner or outer cylinder axially or azimuthally or by varying the gap between the inner and outer cylinders.

The vortical structure is very robust–Taylor vortices can occur in other geometries including between concentric cones and spheres.

For example, vortices occur at the equator between an inner rotating sphere and a concentric, stationary outer sphere ( Figure 5.).

Taylor-Couette Flow – 2009
Richard Lueptow – Northwestern University
Scholarpedia
http://www.scholarpedia.org/article/Taylor-Couette_flow

This four band vortical structure very closely resembles the mainstream model of atmospheric circulation which indicated “the Ferrel Cell did not exist”.

When I started studying weather and climate it was believed there were three cells: the Polar, Ferrel, and Hadley (Figure 1).

In that theory, the complexity was between the Ferrel and Polar Cells.

Then it was argued that the Ferrel Cell did not exist, and air movement between the Polar and Hadley Cells was extremely complicated (Figure 2).

Computer Models and Atmospheric Circulation: A Major Failure – 2011 – Dr. Tim Ball
http://drtimball.com/2011/computer-models-and-atmospheric-circulation-a-major-failure/

This four band vortical structure also provides a mechanism that explains how “the high elevation areas of the Greenland ice sheet” can receive precipitation “which mainly originates from subtropical moisture sources” located around 35 degrees north.

The constraint on T_s, excludes high-latitude moisture source regions as major contributors to the precipitation at high elevations on the Greenland ice cap.

Even optimum tuning of the model with the Weathership A area (62″N, 33″W), not far from South Greenland (Fig. l), as a moisture source leads to deuterium excess values at Site G far from those observed.

For the moment, we tune the model using the subtropical Weathership E (35N, 48W) area as a source of moisture.
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We present evidence that, in contrast to low elevation stations, the high elevation areas of the Greenland ice sheet receive precipitation, which mainly originates from subtropical moisture sources, under present as well as under glacial conditions.

The origin of Arctic precipitation under present and glacial conditions
S. J. Johnsen, W. Dansgaard, J. W. C. White
Tellus (1989), 418, 452-468
http://www.tellusb.net/index.php/tellusb/article/view/15100

The original technique used to observe Taylor–Couette Flow relied upon sandwiching a fluid between an inner rotating cylinder and an outer rotating drum.

In 1888 the French fluid dynamicist Maurice Couette looked at flow induced in a fluid sandwiched in the gap between two concentric cylinders of different sizes.

To induce flow, the inner cylinder was rotated, which drags the fluid next to the wall along with it.

This is now called Couette flow.
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Geoffrey Taylor later modified the device such that the outer drum might be rotated too.

Flow – Philip Ball – 2009 – Oxford University Press

However, this setup is modified in the case of the Earth’s four banded vortical structure:
1) The Troposphere represents a fluid with “axial flow”.
2) The Earth represents an inner rotating sphere.
3) The Isopycnic Level [aka Tropopause] represents an outer rotating sphere.

Lurking in the US Standard Atmosphere 1976 is a rather surprising concept that Atmospheric Science appears to have lost down the back of the sofa in recent years.

First off: What is the Isopycnic Level?

The US Standard Atmosphere 1976 can be used to construct the following definition:

1) The Isopycnic Level is where the Density of Air has been observed to vary by less than two percent [relative to the 1976 standard].

2) The Isopycnic Level is at an altitude of about 8 kilometres in the Earth’s Atmosphere.

Atmospheric Science: The Lost Level
https://malagabay.wordpress.com/2014/07/25/atmospheric-science-the-lost-level/

The troposphere is one of the lowest layers of the Earth’s atmosphere; it is located right above the planetary boundary layer, and is the layer in which most weather phenomena take place.

The troposphere extends upwards from right above the boundary layer, and ranges in height from an average of 9 km at the poles, to 17 km at the Equator.

https://en.wikipedia.org/wiki/Tropopause

Therefore, contrary to the Settled Science, it is likely that Taylor–Couette Flow is actually the primary driver of atmospheric circulation in the Earth’s Troposphere.

“these flow patterns may be analogous to those found in a rotating planetary atmosphere”

Flow – Philip Ball – 2009 – Oxford University Press

http://www.amazon.com/Flow-Natures-Patterns-Tapestry-Three/dp/0199604878/ref=sr_1_1?ie=UTF8&qid=1422871467&sr=8-1&keywords=flow+philip+ball

http://www.amazon.co.uk/Flow-Natures-Patterns-Tapestry-Three/dp/0199604878/ref=sr_1_1?ie=UTF8&qid=1422871467&sr=8-1&keywords=flow+philip+ball

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