The electromagnetic radiation emitted by the sun. The total range of wavelengths of
light emitted by the sun (99.9% in the range from

to

)
is filtered on entering the earth's atmosphere, largely through the absorption by
oxygen, ozone, water vapour and carbon dioxide. Near sea level only light of wavelengths
longer than about

is present. The light from

–

is effective in inducing important photochemical processes since absorption by the
important trace gases, ozone, nitrogen dioxide,
aldehydes,
ketones, etc., is significant in this region.
Source:
PAC, 1990, 62, 2167
(Glossary of atmospheric chemistry terms (Recommendations 1990))
on page 2214
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
https://doi.org/10.1351/goldbook.