大气中尘埃层对电离层电场向下映射的影响

本文首先用分析解方法计算了高纬电离层对流电场向下映射,在平流层、对流层上的水平电场分布情况。地磁场作用使70km以上的电导率呈各向异性,但计算表明,这对极区对流电场向下映射的影响不大。最后,着重讨论了尘埃层使电导率大大下降对电场映射的作用。结果表明,高高度上的尘埃层能完全改变原有的映射图象,而30km以下的尘埃层影响很小。

The Effect of the Dust Layer on Downward Mapping of the Ionospheric Electric Eield

The analytics is used to calculate the downward mapping of the convection fields from the high-latitudinal ionosphere to the lower atmosphere and the distribution of the horizotal electric field in the stratosphere and troposphere. Although because of the existence of the geomagnetic field,the electric conductivity is anisotropic above 70 km, the calculation shows that the effect is not important for the downward mapping. On the othe hand, the dust layer, which reduces greatly the conductivity, can influence the field mapping seriously if the layer lies at the high altitude. There is little influence when the dust layer lies below 30 km.