The Impact of Aerosols on Solar Ultraviolet Radiation and Photochemical Smog
R. R. Dickerson,
*
S. Kondragunta,
G. Stenchikov,
K. L. Civerolo,
B. G. Doddridge,
B. N. Holben
Photochemical smog, or ground-level ozone, has been the most
recalcitrant of air pollution problems, but reductions in emissions of
sulfur and hydrocarbons may yield unanticipated benefits in air
quality. While sulfate and some organic aerosol particles scatter solar
radiation back into space and can cool Earth's surface, they also
change the actinic flux of ultraviolet (UV) radiation. Observations and numerical models show that UV-scattering particles in
the boundary layer accelerate photochemical reactions and smog production, but UV-absorbing aerosols such as mineral dust and soot
inhibit smog production. Results could have major implications for the
control of air pollution.
R. R. Dickerson, S. Kondragunta, G. Stenchikov, K. L. Civerolo, B. G. Doddridge, Department of Meteorology, University
of Maryland, College Park, MD 20742, USA.
B. N. Holben, NASA Goddard Space Flight Center, Greenbelt, MD
20742, USA.
*
To whom correspondence should be addressed. E-mail:
russ{at}atmos.umd.edu
