PREDICTION OF UV-B DOSAGE AT THE SURFACE

Stratospheric ozone reduction is expected to result in increased UV ra diation at the surface. The UV region most sensitive to ozone amount i s that between 280 and 315 nm and is known as UV-B. One response to th e concern about increased UV-B has been the development of systems to provide public UV forecasts, This paper reviews the factors that influ ence UV-B at the ground and describes the basic radiative transfer con cepts that form the basis for forecast schemes. The role of clouds and atmospheric aerosols are also reviewed. The standard definition for t he UV index (UVI) currently used for public forecasts is defined follo wed by a brief summary of three operational UVI schemes.