论文部分内容阅读
从多个角度研究了极区电离层梯度的特性。从整体来分析时,依据单层模型的假设和投影函数只依赖于高度角的性质,利用相邻穿刺点求差来获得投影函数误差。同时,用区域电离层模型获得的不同区域和时段的TEC图作比较。从局部来分析时,用经纬线方向上的测站上空同一卫星的穿刺点来探测水平梯度的方向性。结果表明,磁暴期间,极区和中纬地区的电离层梯度明显增强,但在磁平静期间,不同于中纬地区的梯度较为稳定的方向和大小,极区电离层梯度依然变化迅速,说明极区电离层的特殊形态导致了极区电离层梯度的不稳定。
The characteristics of ionospheric gradient in polar region are studied from many aspects. According to the assumption of single-layer model and the projection function, the projection function error is obtained by making use of the difference of adjacent puncturing points only when it is analyzed from the whole. At the same time, the TEC maps of different regions and periods obtained by the regional ionospheric model are compared. When analyzed locally, the directivity of the horizontal gradient is detected by the piercing point of the same satellite over the station in the latitude and longitude direction. The results show that during the magnetic storm, the gradient of the ionosphere in the polar region and mid-latitude region obviously increases. However, during the magnetic calm period, the gradient and the gradient of the polar region are still changing rapidly, which is different from that of the middle latitude region. The special morphology of the ionosphere in the area leads to the instability of the ionospheric gradient in the polar region.