磁暴期间中低纬电离层暴形态和物理机制分析

本文利用东亚地区１２个低纬电离层台站的测高仪观测数据，对１９７８年８月２７日发生的一次曲型磁暴期间电离层峰值高度和密度的变化进行了分析。采用滑动平均区分开电离层中不同时间尺度的扰动，分析了影响中低纬度电离层暴的几种扰动形态特征，并对其物理机制进行了讨论。结果表明：伴随磁暴急始的磁层压缩，电离层中表现出峰值密度增加和峰值高度下降；磁暴主相期间热层大气暴环流及其所引起的中性大气成分变化控制着电离层的大

MORPHOLOGY ANALYSIS OF MID AND LOW LATITUDE IONOSPHERIC RESPONSE TO GEOMAGNETIC STORM

Using the ionosonde data at 12 stations in East Asia, the response of mid and low latitude ionosphere to geomagneitc storm is analyzed for a typical case of August 27, 1978. Four processes affecting the mid and low latitude ionospheric disturbance morphology are discussed. Accompany with SSC, their appears the sudden increase of the peak density and decrease of its height; the storm circulation causes negative phase usually appears at the main phase of geomagnetic storm with the decrease of the peak density and increase of its height; TID can cause the small scale disturbances superposed in negative phase; and the movement of the equqatorial anomaly crest caused by neutral wind or electric field disturbances is the most important factor to determine the ionospheric storm morphology at stations near the crest.