Salty Thumb wrote:

does anybody know if there is a word or measurement that describes that
efficiency at which a substance traps longer waved solar radiation?

I'm jumping back 30 years or so, but I think the ASHRAE Manual
[American Society of Heating & Refrigeration mumble-mumble] has a
table with material's emissivity and absorbtion rates. [and 'transfer
rate' might be a separate table]

The only part of it I remember offhand is that unglazed brick is very
similar to human flesh-- that's why we think of it as 'warm'.

The 'E' in 'E-glass' *is* quantifiable-- though I'm not sure if all
manufacturers use the same standards yet. [they didn't in 1970] The
emissivity is how much of the heat gets passed through-- not how much
gets absorbed/trapped.

Jim