基于South Pole站和McMurdo站的极区电离层闪烁统计特性

STATISTICAL PROPERTIES OF POLAR IONOSPHERIC SCINTILLATIONS AT THE SOUTH POLE AND MCMURDO STATIONS,ANTARCTICA

利用South Pole和Mc Murdo两站2013年12月至2014年11月期间的电离层相位闪烁数据,统计分析了两站电离层相位闪烁发生率的周日分布和季节分布。统计结果表明,两站的相位闪烁发生率在季节分布上,春秋季明显大于夏冬季;在周日分布上呈双峰结构。在磁中午附近和磁子夜后有较大的闪烁发生率。磁中午附近是因为极隙区的软电子沉降和电离层对流导致的电离层不均匀性,造成较强的无线电波闪烁;磁子夜附近闪烁增强可能是穿越极盖区的等离子体云破碎造成较大密度梯度导致。总体上说,Mc Murdo站的闪烁发生率高于South Pole站,这可能是因为它们所处的磁纬不同所致。

Based on scintillation receiver observations from December 2013 to November 2014 at the South Pole and McMurdo stations,a statistical analysis was performed on the diurnal and seasonal variations of the phase scintillation occurrence at the two stations. The statistical results indicated that the phase scintillation occurrence in spring and autumn is significantly greater than in summer and winter,and that there is a twin-peak structure to the diurnal variation. Phase scintillation occurrence is enhanced at magnetic noon and magnetic post-midnight. Ionospheric irregularities produced by soft electron precipitation and ionospheric convection on the polar cusp could lead to scintillation near magnetic noon. The enhanced occurrence of scintillation at magnetic post-midnight could be induced by a strong density gradient caused by the plasma cloud across the polar cap region. The phase scintillation occurrence at Mc Murdo Station is greater than at the South Pole Station,which might be due to the difference in their magnetic latitudes.