摘要
利用2010年春季民勤加强观测实验的地面辐射资料,分析了民勤沙漠干旱区总紫外辐射的变化特征,并对该地区的紫外辐射进行了估算和模拟。结果表明,紫外辐射和太阳总辐射表现出一致的变化特征,层云对两者的反射能力比卷云强。2010年6月紫外辐射的瞬时最大值为55.92 W·m-2,平均日总量为1.07 MJ·m-2,紫外辐射与太阳辐射比例的平均值为4.7%,其变化范围在3%~9%之间。根据晴空指数(Kt)与最大紫外辐射(UV0)及太阳总辐射(G)建立了民勤地区紫外辐射(UV)的估算方程:UV=2.94+1.22×(Kt×UV0)和UV=0.047G,均能较好地估计该地区的地表紫外辐射。由于受输入参数精度的限制,辐射传输模式SBDART低估了晴空条件下的紫外辐射,低估的总平均值为1.12 W·m-2(约5.6%),变化范围在-2.8~0.2 W·m-2之间。
The variation characteristics of surface total ultraviolet radiation(UV) over desert and arid region in Minqin was analyzed by using the land-surface radiation datum observed at Minqin during the intensive observational experiment in spring of 2010.The results show that:The ultraviolet radiation and global radiation exhibit consistent variation features,and the opaque cloud have much stronger reflected intensity of global and ultraviolet radiations than thin cloud.For the whole period of measurement,the instantaneous maximum of UV is 55.92 W·m^2,and the overall daily average is 1.07 MJ ·m-(-2).The mean ratio of UV to global irradiance is 4.7%,ranging from 3%to 9%.Based on the relationship of clearness index(Kt) and maximum UV(UV_0) and global radiation(G) measurements,we develop two empirical formulae are UV =2.94 + 1.22(Kt X UV0) and UV =0.047G,respectively,which can be estimated surface ultraviolet radiation under all-weather condition.Due to influence by the accuracy of input parameters for model,SBDART radiative transfer model generally underestimates the UV radiation under clear-sky condition,which can be about 1.12 W · m^(-2)(~5.6%),varying within-2.8 to 0.2 W·m^(-2).
出处
《高原气象》
CSCD
北大核心
2014年第2期413-422,共10页
Plateau Meteorology
基金
国家重大研究计划项目(2012CB955302)
国家自然科学基金项目(41305025)
中央高校基本科研业务费专项(lzujbky-2013-207
lzujbky-2013-ct05)
半干旱气候变化教育部重点实验室(兰州大学)开放课题基金
关键词
紫外辐射
沙漠干旱区
晴空指数
辐射传输模式
Ultraviolet radiation
Desert and arid region
Clearness index
Radiative transfer model
