【摘要】 我们在1980—1981年冬季,在兰州市相对高度差为625米的两个点以及郊区对比点同时进行了地面太阳辐射观测,测量了山谷城市上空污染大气,尤其是山谷中的严重污染大气对太阳辐射的削弱。 太阳直接辐射在兰州市区污染大气中的减弱比在郊区大气中大得多,整层大气中的总减弱达72％,而在厚度为625米的河谷大气中的减弱约占整层大气中总减弱的41％。大气中的气溶胶粒子是削弱太阳辐射的主要因子,其对太阳辐射的削弱在整层大气中约占总减弱的66％,在河谷大气中则为96％。因此,地面上垂直于太阳光线面上的太阳直接辐射强度与大气浑浊度系数之间有很好的相关关系,以此建立了两个公式,在干旱地区,可以用它由大气浑浊度系数或到达地面的太阳直接辐射中的一个量计算另一个量。另外,本文还估计了冬季兰州上空河谷大气中气溶胶粒子对太阳辐射的吸收及其辐射加热率,並讨论了污染大气对于地面辐射平衡的影响。更多还原

【Abstract】 In winter ( December, 1980-January, 1981 ) , simultaneous observations of solar radiation were taken at two sites, having difference of altitude of 625m, in Lanzhou and at another contrast site around the city to measure the attenuation of solar radiation and to estimate it only by aerosols in the polluted urban atmosphere especially in the lowest layer of atmosphere where air pollution is very seriousThe attenuation of direct solar radiation in polluted urban atmosphere in Lanzhou was stronger than that in the suburban districts, it was72% of solar radiation within the whole atmosphere and 41% of it was concentrated in the lowest layer of 625 m thickness. The attenuation of sunlight was mainly caused by aerosols,it was 66% of the total attenuation of solar radiation within the whole atmosphere and 96% in the lowest layer. There is a close correlation between the intensity of solar radiation reaching the ground surface and the Angstrom atmospheric turbidity coefficient.Both empirical formulas have been established with which we calculate the Angstrom atmospheric turbidity coefficient from the flux density of solar radiation reaching the ground surface in arid areas or vice versa. At the last, the radiation absorption by aerosols and its heating rate in the lowest layer in winter over Lanzhou are estimated and the effect of air pollution on the net radiation on the ground surface are discussed.更多还原