Absorption, scattering, etc are included in atmospheric path length effect.
High latitudes receive lowest amount of insolation.
Effect of greenhouse gases is to warm surface. Atmosphere emits 96 units of longwave radiation down to surface. High energy photons have shorter wavelengths Visible light is electromagnetic radiation with wavelengths between 0.4 and 0.7 microns. An inversion is when temperature increases with height. Air closest to ground cools as well.