武汉地区电离层电子浓度总含量的统计经验模式研究

由武汉电离层观象台一个太阳黑子周期（1980-1990年）的实测电离层电子浓度总含量（TEC）资料，统计分析得出了武汉地区的一个TEC经验模式，模式很好地再现了武汉地区的TEC观测值，其预测误差在太阳活动高年稍太，低年较小；在春秋两季稍大，冬夏两季较小；在当地时间白天和傍晚稍大，夜间和早晨较小。此外，与国际参考电离层模式IRI的计算结果比较，本模式预测的TEC值更接近于实际观测结果，同时，本文也初步探讨了TEC的半年变化特征和冬季异常现象。

A STATISTICAL TEC MODEL BASED ON THE OBSERVATION AT WUHAN IONOSPHERIC OBSERVATORY

In this paper, an empirical model of ionospheric total electron content(TEC) is obtained by analyzing the TEC data observed at Wuhan Ionospheric Observatory for a solar cycle (from 1980 to 1990). In the model, a linear function was applied to describe the relationship between TEC and solar 10.7cm flux index, and took Fourier series analysis to investigate the diurnal and semidiurnal variations of TEC over Wuhan. The agreement between the prediction by this TEC model and the observed TEC data at Wuhan is quite satisfactoryr: the basic trends and the diurna1 variations are well reproduced. The overall model prediction error is smaller in the years with low solar activity than in those with high solar activity, smaller in winter and summer than in spring and autumn. and in the morning and at night than in the day time and in the evening. The semiannual of TEC and seasona1 anomaly (winter maximum) are also well represented in our TEC model. With the decrease of solar activity, the anomaly is gradually disappeared. In addition, this model is more accurate than International Reference Ionosphere (IRI) model in predicting TEC over Wuhan.