At 20:17 27 March 2017, Duster wrote:
Not exactly transparent. The sky appears blue because air molecules and
sus=
pended particles absorb and scatter certain wavelengths of light. This
ener=
gy is transduced from photons into heat. However, the majority of
advection=
is due to the previous explanation. Not a physicist, so someone else
take
=
a stab.

The downward energy radiated by the sun is short wave and not absorbed by
the atmosphere. The upward energy radiated by the ground is long wave which
is.