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The Environment / Re: Is the greenhouse effect a stupid mistake?
« on: 16/06/2018 21:10:14 »So what happened to the primordial and radiogenic heat?
We leave where it is. It is negligible for surface temperatures, unless you are sitting on a volcano.
Rather the GHE is based on the unreasonable and simply wrong assumption that absorptivity of Earth was about 0.7, while emissivity was a straight 1.
Did it occur to you that the values of 1 and 0.7 might be measured, rather than assumed?
I thought was quite explicit on that. While the precise value of the albedo (and thus absorptivity) is both in discussion and a matter of ongoing research, I do not question its dimension. It will be around 0.3. Emissivity however is not being discussed, nor being measured. It is a dogma that it shall be 1, any discussion or research on the subject will be considered heretic.
But, as always, let us try a dialectic approach. One could use the secretive devide called "google" to argue the opposite. Here we have an article of NASA on the subject.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19990100634.pdf
"To date, however, high quality surface emissivity data have not been readily available for global applications. As a result, many remote sensing and climate modeling efforts have assumed the surface to radiate as a blackbody (surface emissivity of unity)."
Right, it is all based on an assumption. But NASA comes to help. So they simply put a satellite into space to measure emissivity, which should clarify the subject once and for all.
But wait a moment! How could you measure emissivity? You can measure LWIR which will depend on a) surface temperature, b) its emissivity, c) GHGs absorbing and emitting it and d) even LWIR reflected by the surface. How will you know what is what? Seems the attempt is doomed before it started.
"The resulting broadband emissivities were used with a surface longwave model to examine the differences resulting from the use of the emissivity maps and the blackbody assumption"
Ok, here we have it. A model will do the trick. To models however the old programming rule applies: garbage in, garbage out. Ultimately even NASA "measurements" are based on .. assumptions. Just read the article, it is discussing assumptions and models back and forth.
What is worse, we even know they got it all wrong. They made a pretty childish mistake in this paper. On page 4 they quote labratory measurements on the emissivity of water (among others), which may be quite accurate. But the emissivity of water is a way more complicated than what they assumed, as it all depends on the angle of observation. You will need Fresnel equations to derive the hemispheric emissivity, which is much lower than vertical emissivity. It is not so hard to do, and it is a great starting point for any complicated model, if you have some "knowns" to compare with the "unknowns", just like in a crossword.
You can not see that in the ill fated grey maps in that named article, but they also have a shorter version with a map that is actually readable. There they have ocean water with an emissivity of 0.99-0.995. And that is simply untrue.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20040086575.pdf
Now that is bad science. I could also point towards some more reasonable data like in the link below.
https://www.star.nesdis.noaa.gov/smcd/spb/LANDEM/prod_AMSRE.php
In a nutshell: yes, there are attempts being made to "measure" emissivity, which is hard to do for the named reasons. In any case emissivity is lower than 1 by a disputed margin. How does the church of climatology account for it? Not at all, they hold on to the assumption emissivity = 1, period. And that is very bad science too.