Absorbance of incoming sunlight
• Of the total incoming sunlight of all wavelength
that impinges upon the earth, about 50% is
absorbed at its surface by water bodies, soil,
vegetation, buildings, and so on.
• A further 20% of the incoming light is absorbed
by water droplets in air (mainly in the form of
clouds) and by molecular gases--- the UV
component by stratospheric ozone, O3
, and
diatomic oxygen, O2
, and the IR by
carbondioxide, CO2
, and especially water vapor