Measurement of solar ultraviolet radiation at a temperate and a tropical site using polysulphone film

Measurements of solar ultraviolet radiation (<320 nm) have been made with polysulphone film at a temperate and a tropical site and compared mean monthly values of the fraction of ultraviolet in solar radiation are calculated which allow an estimate of ultraviolet dose to be made from a knowledge of total solar radiation.While the data demonstrate the marked effect of sun elevation on the ultraviolet fraction of solar radiation they also indicate the effect of seasonal variation in the thickness of the ozone layer above the temperate site.It is also shown that whereas sunlight makes by far the major contribution to total solar radiation, skylight is of prime importance as regards ultraviolet radiation.