第23太阳活动周武汉站电离层TEC特征分析

Characteristic Analysis of Ionosphere TEC at Wuhan Station During 23rd Solar Cycle

利用武汉站(30.5°N,114.4°E)1997年1月1日至2007年12月31日电离层TEC、太阳黑子数及地磁指数等资料.分析了第23周武汉站TEC的周日变化、季节变化、半年变化以及与太阳活动的相关性等特征;以2006年4月13-1 7日发生的磁暴为例,讨论了武汉站TEC对磁暴的响应以及可能的机理.结果表明.武汉站电离层TEC在太阳活动高、低年均呈典型的周日变化特征;冬季异常和半年异常特征明显,且受太阳活动强弱影响;TEC和太阳黑子数年均值相关系数为0.9611;TEC对磁暴的响应可能是由磁层穿透电场和中性风共同作用导致的,具体影响机制有待深入研究.

By using Total Electron Content （TEC） at Wuhan station （30.5°N, 114.4°E）, sunspot numbers and geomagnetic index from 1997 to 2007, some typical characters such as diurnal variation, seasonal variation, and semiannual variation, correlation with solar activity were analyzed. A case study was made on the responses and possible mechanism of ionosphere TEC to the magnetic storm during 13--17 April 2006. Analysis results show that diurnal variation exists constantly in high and low solar activity. Some features like semiannual anomaly and winter anomaly in TEC had been reported, but changed with solar activity. The correlation coefficient for yearly sunspot number with TEC is 0.9611. TEC correlates with the geomagnetic AE well. The response of TEC to geomagnetic storm may be caused by penetrating electric fields and neutral winds, and the specific mechanismneeded to be analyzed in the future.