Saturday, November 12, 2011
Radiation Versus Conductivity
I downloaded a spreadsheet from the University of Virginia which had this plot which I hope came out okay after the transitions I had to make to post it above. It is the relationship between a blackbody at temperature T and T/2. The fourth power relationship with temperature is rather striking.
So since I am blogging away about how the conductivity in Antarctica was not well considered in the Global Warming theory, it seems people have absolutely no clue what I am talking about. Basically, the big tall curve is the Equator and the small hard to see one is Antarctica. Now do you think that CO2 might have a bigger impact in the energy flux of the big curve or the smaller one? Looks to me like CO2 might have about one fourth the impact in Antarctica.
Now how about that tiny conductive flux that is the Rodney Dangerfield of Climate Science? In just about every thermodynamic problem I have ever encountered , neglecting conductive heat transfer was not a terribly smart idea. At the Equator, the Thermal Conductivity of air is about 0.0257W/m.K, a pretty small number. In the Antarctic, that number drops to 0.0204W/m.K at -50 degrees C. 0.0204 is 79.4% of 0.0257 according to my calculator. That seems to mean that in Antarctica, the conductive flux potential would be 79% less than at the Equator. What that flux might actually be would depend on the possible differential temperature. The radiant impact of CO2 forcing would be about a quarter of what it would be at the Equator. That would depend on the average temperature of the CO2 radiant layer and or course the emissivity between that source layer and the surface.
Because of the less than stellar quality of the temperature data in the Antarctic region, I can't even come up with a good guess yet what the approximate values are, but it seems like it may be something worth figuring out.
As I mentioned before, CO2 has a non-linear impact on the thermal conductivity of air that's peak value is at -20 degrees C.
I borrowed this image from Bob Tisdale where he posted on Watts Up With That I wonder what temperature that big dip at -60 latitude might be?
Now I realize that my time series analytical skills are poor. That I am not the most eloquent writer on the internet. But I used to get paid pretty good money to measure heat flows and energy efficiency. That dip looks like a pretty efficient application of conductive heat transfer to me. Whatta ya think?