Machine learning enhanced NARMAX model for Dst index forecasting

As many systems and equipment are sensitive to magnetic disturbances, it is important to understand the magnetosphere system, to reduce the negative effect caused by severe space weather situations. The disturbance storm time (Dst) index is used to measure the magnetic disturbances and it is correlated with solar wind variables. This study presents a new machine learning enhanced NARMAX (MLE- NARMAX) model for 3 hours ahead forecasting of Dst index. An important advantage of the MLE-NARMAX model is that it provides a transparent and explainable model structure. The model performance is tested over three typical strong storm periods, where the prediction skills are 0.9734, 0.9598 and 0.9206 in terms of correlation, and 0.9474, 0.9173, and 0.8333 in terms prediction efficiency (PE). Compared to the conventional NARX model, the MLE-NARMAX produces better model predictions.