ANALYSIS OF THE ESSENTIAL CHARACTERISTICS OF THE BIOLOGICALLY WEIGHTED ULTRAVIOLET SOLAR RADIATION QUANTITY, DUV (Damaging Ultraviolet Radiation), BASED ON OBSERVATION OF THE SPECTRAL ULTRAVIOLET IRRADIANCES

Ozone depletion in the stratosphere is now recognized as a major environmental problem, because which results in a significant increase in solar ultraviolet radiation that reaches the surface of the Earth. The purpose of this study is to know characteristics of DUV that is one of the biologically weighted ultraviolet radiation. Through analysis of observed spectral ultraviolet irradiances and global solar radiation values at Sapporo, Kanazawa, Tsukuba, Kagoshima and Naha, the followings were shown:(1) The tendency of increase and decrease of daily accumulated DUV during the years 1990-1996. (2) Seasonal change of daily accumulation of DUV. (3) The ratio of DUV to global solar radiation based on daily totals. (4) The correlation between DUV and global solar radiation.