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3 - Home experiments to test the Woods experiment
#1
(07-17-2011, 02:47 PM)Climate Realist Wrote: R Wood's famous experiment should be repeated using KBr sheets and confirmed!! (if it has not already been!) I would like to run that one myself.

Sounds a great suggestion Climate Realist, please expand upon your above comment.
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
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#2
The RW Woods experiment disproved the Greenhouse theory early in the 20th century by showing that Arrhenius's idea of heating from "back radiation" is false.

Woods made two small greenhouse chambers with black cardboard walls one with a glass roof and the other with a KBr (or rock salt) sheet roof. Glass is impervious to IR whereas KBr salt sheets allow IR to pass unhindered (hence why KBr salt discs are used in IR spectroscopy).

There was a thermometer in each chamber. The temperature of both chambers rose to the same temperature on a sunny day.

This experiment proves that back radiation cannot heat the ground or the air. The glass roofed chamber would have had back IR radiation originating in the black cardboard sides reflected from the glass back into the chamber- thus "trapped " IR. If the greenhouse effect was real, then the glass roofed chamber would have been significantly hotter than the KBr/rock salt roofed chamber. The fact that both chambers reached the same temperature proves that, as I have been saying at length on this forum and others, that back IR cannot cause a greenhouse effect. The greenhouse effect is all from the slowness of convection - or in this case, trapping air and preventing heat loss by convection altogether!

http://www.giurfa.com/gh_experiments.pdf

Woods then repeated the experiment with a sheet of glass above each chamber to prevent direct IR having any influence.

http://educate-yourself.org/cn/greenhous...eb09.shtml

http://my.billingsgazette.com/post/reaso...AB993.html


The difficulty is in acquiring large enough good quality sheets of KBr or rock salt!
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#3
Hello All,
Below is a link to Professor Nasif Nahle's repeat of Wood's 1909 experiment.

http://www.biocab.org/Wood_Experiment_Repeated.html
Experiment on the Cause of Real Greenhouses’ Effect
- Repeatability of Prof. Robert W. Wood’s experiment

By Nasif S. Nahle

University Professor, Scientist, Scientific Research Director at Biology Cabinet©
Monterrey, N. L., Mexico.


The pdf of which is attached below.
Final version attached 21st July 2011.


Attached Files
.pdf   Repeatability of Professor Wood 1909 Experiment on Greenhouse Effect Prof. Nasif Nahle July 2011.pdf (Size: 2.41 MB / Downloads: 259)
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#4
Thanks for the link, Derek, that is exactly what I have been saying for years! Restriction of convection, not radiation!

"
ABSTRACT
Through this controlled experiment, I demonstrate that the warming effect in a real greenhouse is not due
to longwave infrared radiation trapped inside the building, but to the blockage of convective heat transfer
with the surroundings, as proven by Professor Wood in his 1909 experiment"

It's all over CR site now ! http://climaterealists.com/index.php?id=8073

I'd heard about the experiment some time ago, but was asked to keep quiet about it till it was published, exciting stuff indeed!!

Great work, Dr Nahle!
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#5
(07-18-2011, 08:56 AM)Climate Realist Wrote: Thanks for the link, Derek, that is exactly what I have been saying for years! Restriction of convection, not radiation!

Which was exactly the point of my,
What does a thermal image of a greenhouse actually show? Post 2

Does that not show radiation is a lot weaker than conduction and convection, and
that "wet" surfaces (plants transpire and are therefore "wet" in this regard) are even cooler, ie, latent heat losses are the most powerful?
Certainly my lawn is never as hot, after a couple of hours in direct sunlight, as the concrete slab path next to it is..
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#6
Some interesting comments and analysis on the Wood's experiment HERE. (still reading the Nahle paper.)
Scroll down to this heading:

3.3 Returning to Wood's Experiment to Test Arrhenius' Backradiation Hypothesis

Quote:Taking Arrhenius (1906a) into account, we may extend his backradiation hypothesis to this particular situation. In this case, the glass lets through the light of the sun but absorbs 85% of the terrestrial infrared radiation radiation returning to space - at least that emitted above 2900nm. We may suppose that this 85% is of the half of the radiation that is absorbed above 2900nm and is augmented by about 15% of the other half of the outgoing infrared radiation based on the numbers from Nicalau and Maluf (2001). That is a total absorption of 50% of the outgoing radiation. This radiation is subsequently emitted from the glass itself; half radiated outside and half radiated back inside the miniature greenhouse. The amount of radiation reaching the bottom of the greenhouse is equal to that directly received from the sun plus the 25% radiated back by the glass. Although halite is more transmissive than glass in the visible spectrum, this is offset by the fact that halite is much more reflective than glass in the visible spectrum (Lane & Christensen, 1998). The difference in light transmission is less than 5%. Thus in the case of this experiment, the glass greenhouse bottom can be said to have received at least 120% (100-5+25) of the radiation received by the halite greenhouse bottom according to the hypothesis of Arrhenius. Thus we expect the temperatures of the respective greenhouses to reflect this significant difference in hypothetical radiation.

Much more with some math follows.
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
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