What the Pirani guage implies about atmospheric heat transport.

Tom Shula explains how the behaviour of the Pirani gauge precludes any significant greenhouse gas effect: YouTube | white paper (pdf) | WUWT

We can use the behaviour of the Pirani gauge to estimate what kind of heat transport should dominate in each layer of the atmosphere. The IPCC say radiative cooling dominates everywhere in the atmosphere; even at ground level. They are completely wrong. Not because 'the science is wrong'; but because the politicos politicized the science so much - they make it up.

The Pirani guage implies:

mode of heat transport	pressure	altitude	regions
convection	above 4 Torr	below 35km	troposphere, tropopause, lower stratosphere
conduction	0.1 to 4 Torr	35 to 65 km	upper stratosphere, stratopause, lower mesosphere
radiation	below 0.1 Torr	above 65km	above mid-mesosphere

Derivation of table above

In his book "A User's Guide to Vacuum Technology", 3rd edition, John F. O'Hanlon's presents the following diagram on page 88 to show that as one goes from atmospheric pressure to a vacuum, the cooling of the Pirani gauge sensor wire is dominated, in turn, by convection, conduction and radiation - the 3 heat transport mechanisms.

O'Hanlon's diagram did not label the axis because the precise curve one gets depends on the gas. But both axis are logarithmic. The basic outline (shape) of the curve is the same for all gases. So we can superipose the points - where convection gives way to conduction, and conduction gives way to radiation - onto the diagram supplied by Tom Shula. The enables us to find specific pressures at which these cross-overs happen.

convection (iii) gives way to conduction (ii)	~ 4 Torr
conduction (ii) gives way to radiation (i)	~ 0.1 Torr (100 microns).

The diagram below relates altitude to atmospheric region

Conclusions

pressure

mode of heat transport		altitude	regions
convection	above 4 Torr	below 35km	troposphere, tropopause, lower stratosphere
conduction	0.1 to 4 Torr	35 to 65 km	upper stratosphere, stratopause, lower mesosphere
radiation	below 0.1 Torr	above 65km	above mid-mesosphere

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The table below, found here, associates specific pressures with altitude.