到达中国陆面的生物有效紫外线辐射强度分布

随着大气臭氧层的日趋变薄,估算到达陆面的太阳紫外线辐射变化,评估对人体健康的影响日趋成为环境健康研究的一个重要课题。基于DISORT辐射传输模型,从生物健康效应的角度提出了估算陆面有效紫外线辐射强度的方法,并采用LibRadtran软件包UVSPEC模型以及GIS空间分析技术模拟了2000年1月和7月到达中国陆面的生物有效紫外线辐射强度空间分布,讨论了臭氧、云量、地表反照率等因素对陆面生物有效紫外线辐射强度的影响,研究了基于云量、海拔数据修正陆面紫外线辐射的方法。另外,还系统分析了2000年1月、7月我国陆面生物有效紫外线辐射强度的空间分布特征,1月份辐射强度是低纬度较高,而7月份是中高纬度较高。UVA和UVB陆面辐射强度分布明显不同,特别是7月份,UVB辐射强度的高值区域较UVA明显偏向低纬度地区。UVB的生物有效辐射强度大约是UVA的6倍。

Distribution of biologically effective solarultraviolet radiation intensity on the ground in China

With the stratospheric ozone layer turning thinner and thinner,to calculate solar ultraviolet radiation reaching the Earth's surface and assess its effects on human health has become a focus.Based on radiation transmission model of DISORT,a new method to calculate biologically effective ultraviolet radiation intensity on the ground is identified and spatial distribution of biologically effective ultraviolet radiation intensity in China in January and July,2000 is simulated using UVSPEC model of LibRadtran software package and GIS spatial analysis technique.This paper discusses the effects of the spatial and temporal variation of atmospheric ozone,cloud cover and ground albedo on ground ultraviolet radiation intensity,and explores the correction method with the result of DEM and cloud cover.In addition,it systematically analyzes the spatial distribution characteristics of ground biologically effective ultraviolet radiation intensity in China in January and July,2000.Ultraviolet radiation intensity is higher in low latitude than that in mid-high latitude in January and on the contrary in July.Because of the higher altitude and lower ozone thickness,the ultraviolet radiation intensity is higher on the Tibetan Plateau than in the other regions in January.There are different radiation intensity distribution patterns between UVA and UVB in January and July because ozone can absorb more UVB radiation than UVA.Higher radiation distribution of UVB is closer to the low latitude than that of UVA.Owing to the higher relative spectral effective coefficient against 270nm of UVB,normalized UVB biologically effective radiation is about six times more than that of UVA.