Emissivity refers to a material's ability to emit or release heat energy in the form of infrared radiation. A high emissivity means the material can easily emit heat energy, while a low emissivity indicates that the material retains heat well.
«The new definition of effective emissivity of non-isothermal rough surface and its approximate expression for continuous canopy vegetation» Chen IEEE explore (jennifermarohasy.com)
The real GHE must be reduction of surface emissivity by GHGs turning off that emission. (joannenova.com.au)
Calculated Aa, Ed / Aa, Su / Eu, Su / OLR, all with emissivity = 1, are in columns M to P. (scienceofdoom.com)