通过测量氡的放射性来监测大气稳定度的新方法

介绍了一种通过测量氡和其短周期衰变产物的自然放射性来监测大气稳定度的新方法,该指标反映了低层大气边界层的混合特性,能够反映一次污染物的稀释扩散特征.将这种方法测量的大气稳定度与通用的帕斯奎尔分类法计算的稳定度进行对比,该方法不仅能准确反映大气稳定度长期趋势和昼夜变化,还能反映大气稳定度的瞬时变化,是解析环境污染数据,特别是一次污染物的有利工具.2007年在兰州市的观测结果显示PM10与大气稳定度的观测数值有很好的一致性趋势,表明低层大气的混合特性是决定一次污染物浓度的关键因素.

Measurement of atmospheric stability index by monitoring radon natural radioactivity

A method to measure atmospheric stability index (ASI) by monitoring the natural radioactivity of radon and its shot-live decay products with OPSIS SM200 monitor was introduced. The index gives information about the dilution properties of the lower boundary layer and allows to highlight the relevant role of the dilution factor in determining pollution events. The measured ASI data had good agreement with the atmospheric stability classes calculated by Pasquill method. ASI can indicate the diurnal variation and long-term trends of atmospheric stability, as a useful tool to interpret pollution events, especially for primary pollutants. Measurement data taken in Lanzhou in 2007 showed that PM10 trend was consistent with the ASI trend, which indicates that mixing properties of lower boundary layer is the key factor determining primary pollutants’ concentration.