It follows a "radiative process" because that's how physics works.
I can and have refuted his work, what you can't do is intelligently defend it.
Nikolov/Zeller argue that it's actually only the pressure which influences the surface temperature, and that GHG are irrelevant.
To prove this they used a mathematical model that in reality only shows that the ideal gas equation works, they dismiss the GH effect without offering any evidence of an alternative explanation of the higher planetary temperature.
ie With SB we arrive at an equilibrium temperature something like this: