Connection between emissivity and albedo

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Emissivity and albedo are closely related, particularly for opaque objects, where their sum equals one. Albedo refers to the reflectivity of a surface, while emissivity measures how well it emits thermal radiation. At a specific wavelength, emissivity can equal albedo, preventing heat transfer from colder to hotter objects through radiation. There is also a mention of spectral weighting in defining albedo. The discussion clarifies the relationship between these concepts and corrects initial confusions regarding their definitions.
mike133
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Hi,
I am studying thermal radiation. Does anyone know what is a connection between emissivity and albedo.
Regards,
Mike
 
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Albedo is a reflection, so emissivity + albedo = 1, for opaque objects. There's probably some spectral weighting involved in the definition of albedo.
 
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Andy Resnick said:
Albedo is a reflection, so emissivity + albedo = 1, for opaque objects. There's probably some spectral weighting involved in the definition of albedo.
You are confusing emissivity and reflectivity. [No, I'm confusing albedo and absorption. Sorry.]

Emissivity is equal to albedo at a given wavelength. If they were not equal, the heat could flow from colder object to hotter one via radiation.
 
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I think Andy was correct.

For non transparent bodies:
emissivity+albedo=1
 
Yeah, you're right. I somehow confused albedo and absorption. Emissivity+albedo=1 is correct.
 

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