测量边界层辐射对研究地气系统相互作用有重要意义,城市边界层辐射的变化影响着城市局地气候和环境。目前辐射测量仪器的精度不能满足城市大气边界层辐射分层测量的特殊要求。2004年10~12月,在北京325m气象铁塔上的280m和2m高度上分别安装了长波辐射表和短波总辐射表,进行辐射测量。为提高辐射测量精度,采取多种方法,进行了较细致的误差分析和资料订正,使两层不同高度上仪器的一致性得到明显提高,计算订正了铁塔塔体发射的长波辐射对辐射测量的影响,取得了比较合理的结果。辐射观测资料分析表明,边界层内辐射通量密度随高度的变化是明显的,在不同环境条件下对边界层结构有着重要作用。
Measurement of radiation in boundary layer is very important for studying on interaction between air and land or sea. The change of radiation in urban boundary layer influences on local climate and urban environment. But the meteorological radiation instruments can't satisfy the special request for studying on the urban atmospheric boundary layer. The experiment was conducted in Beijing from October to December 2004 , with the pyranometer and pyrgeometer installed on the 325 m meteorological tower at the heights 280 m and 2 m, respectively. For improvement of the accuracy and the agreement of the different radiation instruments on the different heights, several analysis, data corrections and carefully designed comparisons have made and the results are fine. The calculations to eliminate the influence of the long wave radiation emitted on radiation measurement from meteorological tower that have got reasonable results. The data analysis shows that the variation of radiation flux with height in boundary layer is obvious, and the influences on boundary layer structure are important under different environments and conditions.