基于EOF分解的区域电离层VTEC预报模型研究

A Regional Ionospheric VTEC Prediction Model Based on EOF Decomposition

区域电离层的监测和预报是一项具有重要意义的工作,也是目前一个比较热门的研究方向。据此,着重研究了区域电离层的预报模型,以期能够为区域内的用户提供短期的电离层VTEC预报信息。提出了一种基于EOF分解的区域电离层VTEC预报模型,该模型同时考虑了VTEC时间序列的时间分布特性和空间分布特性:首先通过EOF分解提取随时间变化的时间分量和不随时间变化的空间分量,并对时间分量进行预测,最后通过EOF重构获取VTEC预报值。采用IGS提供的195个格网点的VTEC数据对模型进行验证,结果显示,基于EOF分解区域电离层VTEC预报模型的预报平均相对误差为4.05%,相比于普通的时间序列模型其精度可以提高40.3%。

Monitoring and forecasting the regional ionosphere is a significant work and research orientation.It focuses on the forecasting model of regional ionosphere to provide users with real-time ionospheric VTEC（Vertical Total Electron Content）information.Based on the EOF decomposition,the regional VTEC prediction model is proposed here.Firstly,time-varying components and the space components which do not change with time are extracted by EOF decomposition.Then,time-varying components are predicted and the final VTEC forecast values are generated by EOF reconstruction procedure.195 IGS grid VTEC data are used.The results show that the EOF-ARIMA model has an average relative error of 4.05%.Compared to the AMIMA single-point prediction model,the accuracies of EOF-ARIMA model could improve 40.3%.