D- and E-Region Incoherent-Scatter Radar Observations at Sondrestrom, Greenland

格陵兰岛的Sondrestrom非相干散射雷达最近升级了一种新的雷达数据采集系统，可以以比以往更高的空间分辨率进行测量。本文提出的工作将利用这些改进来研究电离层物理中两个有趣而重要的问题。首先是在接近110千米的高度出现金属离子薄层。这些层已经在低纬度地区被观测到，并被解释为由于中性风中的剪切造成的大气物质的集中。在高纬度地区，这种解释并不适用，因此这些层在Sondrestrom资料中的出现是一个重要的突破。拟议研究的第二个主题是在大磁暴期间发生在高纬度地区的高度低于100公里的电离增强。这种电离是由来自太阳的高能质子产生的，在如此低的海拔地区，它的存在会对高纬度地区的无线电波传播产生巨大的变化。

The Sondrestrom incoherent scatter radar in Greenland has recently been upgraded with a new radar data acquisition system that allows measurements to be made with a higher spatial resolution than ever before. The effort proposed here will take advantage of the improvements to study two interesting and important problems in ionospheric physics. The first is the appearance of thin layers of metallic ions at altitudes near 110 km. These layers have been observed at lower latitudes and have been explained as the concentration of meteoric material due to shears in the neutral winds. At high latitudes this explanation does not apply, so that the appearance of these layers in the Sondrestrom data is an important breakthrough. The second topic of the proposed study is the enhanced ionization at altitudes below 100 km that occurs at high latitudes during large magnetic storms. This ionization is produced by energetic protons from the sun and its presence at such low altitudes can produce dramatic changes in radiowave propagation at high latitudes.