§ Solar Constant (S)
=
solar flux density reaching the Earth
= 1370 W/m2
§ Solar energy incident on the Earth
= S x the “flat” area of the Earth
= S
x p R2Earth
§ Solar energy absorbed by the Earth
= (received solar flux) – (reflected solar
flux)
= S p R2Earth – S p R2Earth x
A
= S p R2Earth x
(1-A)
A is the planetary albedo of the Earth, which
is about 0.3.