利用曙暮气辉光度观测研究钠层

通过对钠原子曙暮气辉的18次观测确定了北京北郊上空不同季节钠原子气柱总含量和钠层重心高度等结构参数。结果表明:春夏季钠层重心位置高,秋冬季位置低.冬季观测的平均钠层重心高度为85.67公里;钠原子气柱总含量冬季明显高于其它季节,1月和12月的含量约为6月的7.5倍;冬季钠层也相对地厚.钠层重心高度及总含量的季节变化不仅受D层顶中性和离子化学的制约,而且受到垂直风及子午向或纬向环流的很大影响.

AN INVESTIGATION OF THE SODIUM LAYER FROM TRILI-GHTGLOW OBSERVATION WITH PHOTOMETER

The sodium column abundance and the peak density height of the twilight sodium layer are measured with a narrowband filter photometer from 19 twilightglow observations at the northern suburbs of Beijing between March 1987 and January 1990. It is shown that there are higher layers in spring and summer and lower layers in autumn and winter. The layer thickened in winter. The average height of the peak density is 85.7km for eight winter evenings. An annual variation by a factor of 7.5 in the sodium column abundance with maximum in winter is observed. The height and concentration variations of the sodium layer are triggered not only by the sodium photochemistry, but also by some dynamic processes.