北京地区臭氧层损耗、气溶胶污染与紫外辐射的变化

对北京地区臭氧层损耗和气溶胶污染对紫外辐射量变化的影响进行了计算。结果表明，当臭氧总量减少１％－３０％时，ＵＶ－Ｂ对ＤＮＡ危害效应的辐射放大因子（ＲＡＦ）从２．３增加到４．２。城区和乡村环境的气溶胶污染使ＵＶ－Ｂ日辐射总量分别降低４５％和１０％。如是仅考虑臭氧总量的变化，１９８０－１９８９年间ＵＶ－Ｂ辐射量年变化率为１．４％，当考虑气溶胶因素的变化后，ＵＶ－Ｂ辐射量年变化率为－０．７％，这与实际观

Ozone Layer Depletion, Aerosol Pollution and Solar UV-B Radiation at the Ground

Ozone layer depletion and aerosol pollution have an influence on the solar ultraviolet radistion reaching the ground. A compunction indianaes that the radiation amplification factor (RAF) for a DNA damage varies from 2.3 to 4.2 when a reduction in column ozone goes from 1% to 30%. Since the industrial revolution, the daily UV-B radiation in urban and rural areas has decreaSed by about 45% and 10%, respeCtively, that Can be attributed to aerosol pollution. The computed UV-B radiation due to the ozone reduction in Beijing shows an increasing trend at an average annual rate of 1.4% during the Period of from 1980 to 1989. By taking the variations in atmospheric aerosol concentration into account,the computed UV-B radiation shows a trend of negstive shift at an annual rate of 0.7%. These variations in UV-B radiation are found to be close to those measured in the Alpine regions(47°N) and the United States (30-50°N).