地磁暴期间中国中低纬电离层的CIT研究

利用电离层层析成像技术(Computerized Ionospheric Tomography, CIT)处理115°E子午圈附近6个台站的GPS观测数据, 分析了2004年11月地磁暴期间中国中低纬电离层的响应情况. 结果表明, 电离层呈正相扰动, 且不同高度上的响应不同, 800 km以下电子密度有不同程度的增加, 且在峰值高度附近增幅最大, 800 km以上地磁暴的影响并不显著; 伴随地磁能量的注入, 赤道异常峰极向扩展; 随磁扰强度的降低, 电子密度也逐渐恢复至平静水平. 这些结果与以往的理论和观测结果一致, 初步估计扰动是由热层暴环流引起的, 并受到赤道异常峰移动的影响.

Study of Computerized Ionospheric Tomography Under Ionospheric Storm Conditions

The characteristics and development of the low-and-mid latitudinal ionospheric storm during the magnetic storm in November, 2004 are studied using GPS observations from 6 stations along 115°E meridian. The results from tomographic reconstruction method show that the ionospheric storm during this magnetic storm mainly exhibits the positive storm phase, and the positive deviations of electron density are not only latitude dependent but also height dependent. The Equatorial Anomaly (EA) crest moves poleward as a result of enhanced energy deposition into the high latitude ionosphere. The electron density and TEC gradually recover to the quiet level in the first recovery phase. These results are in good agreement with previous studies, and the ionospheric effects can be attributed to the storm circulation theory superimposed with the movements of EIA crest.