Sunday, April 10, 2016

The Albedo-Emissivity Paradox

I would like to share with you a paradox I have uncovered during my investigation into thermoelectrics ('IR spectroscopy') that I call the albedo-emissivity paradox. 

The albedo of snow is very high as it reflects light, while at the same time the emissivity of snow is also very high (near 1, which implies it absorbs and emits IR radiation, and does not reflect IR (thermal) radiation). Snow and ice are near perfect black bodies.
But, does snow really not reflect IR (heat)? In any other context IR is thermo radiation, and related to heat and temperature. Snow absorbs this IR but does not reflect it? Can this be true? I don't think so. Black painted or dyed snow will melt faster that white pure snow. 
I don't think anyone has discussed this paradox.  Where have I - or scientists gone wrong? 

I have a possible answer to this, and the clew is aluminium and other shiny metals - all of which all have low emissivities - next to 0.  Other materials don't have such a low emissivities: not water, and not snow - they have high emissivities. 

Thermopiles and their mechanism thermoelectrics are the problem.
I will write up my theory as soon as I have time.

Blair


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