【摘要】 本文利用经验正交函数(EmpiricalOrthogonalFunction,简称EOF)分析了武汉电离层台站一个太阳黑子周期(1980年4月～1990年12月)的实测电离层电子浓度总含量(TEC)资料,在此基础上构建了一个武汉地区的TEC月中值的经验模式.结果表明:(1)以EOF分析观测数据具有一定的物理意义,其基函数表征TEC的日变化,系数表征TEC的长期变化;(2)EOF技术展开收敛速度快,很少数低阶项即能反映TEC的主要变化,采用经验正交函数建模可以用较少的参数表征较复杂的物理过程.此外,本文还就TEC模式的外部驱动量的改进问题作了一些探讨,发现用F107A(10.7cm太阳辐射通量F107的81天滑动平均值)作TEC建模的外部驱动量能够更好地提高EOF模式的精度和稳定性.更多还原

【Abstract】 The empirical orthogonal function (EOF) analysis has been used to develop an empirical model of total electron content (TEC) median over Wuhan from April 1980 to December 1990 The result reveals that the EOF functions may signify certain physical processes. Its base function signifies the diurnal variation of TEC, and the coefficient signifies the long term variation of TEC. The EOF’s rapid convergence and fairly good precision can represent the complex process in a simple way. The first three EOFs are able to explain almost 997% of the TEC data variance. Furthermore, some discussions have been done to improving the external driver of the model. It is found that replacing F107A as the external driver can improve the model’s precision and stability.更多还原