基于深度学习的太阳风多参数预测

    Multi-parameter Prediction of Solar Wind Based on Deep Learning

    • 太阳风中高速等离子体流与地球磁层相互作用会引发地磁暴等空间天气事件, 进而影响现代技术系统的稳定运行. 本文利用具有片段嵌入和交叉注意力机制的深度学习模型TimeXer来挖掘太阳风参数间的复杂依赖关系, 预测未来72 h的4个太阳风参数. 实验结果表明, TimeXer仅利用历史太阳风数据及时间信息, 即可对太阳风速度、动压、质子密度、质子温度分别实现47.65 km·s–1, 1.00 nPa, 3.13 cm–3, 4.49×104 K的预测绝对误差, 与现有的传统及深度学习方法相比, 该模型性能更优, 即使在磁暴期间, 也能较准确地捕获各太阳风参数的整体变化趋势; 基于太阳风参数依赖关系的联合建模预测优于单参数预测; 对模型交叉注意力权重的分析可反映各输入参数对不同太阳风参数预测的相对重要性.

       

      Abstract: When interacting with the Earth’s magnetosphere, high-speed plasma flows in the solar wind can trigger space weather events such as geomagnetic storms. Therefore, accurately forecasting solar wind parameters is critical for early warnings of space weather and the stable operation of modern technological systems. This study employs TimeXer, a deep learning model incorporating patch embedding and cross-attention mechanism, to explore the complex dependencies among solar wind speed, dynamic pressure, proton density, and proton temperature. This model can accurately predict solar wind parameters for the next 72 hours by only using historical solar wind data and time information, and it is also interpretable. Test results during low solar activity level (Year 2021) and high solar activity level (Year 2024) periods demonstrate the following conclusions. TimeXer’s Root Mean Square Errors (RMSE) for solar wind speed, dynamic pressure, proton density, and proton temperature are 68.39 km·s–1, 2.12 nPa, 5.02 cm–3, and 8.83×104 K, respectively, while the Mean Absolute Errors (MAE) are 47.65 km·s–1, 1.00 nPa, 3.13 cm–3, and 4.49×104 K. Compared with traditional and advanced deep learning methods, TimeXer exhibits superior performance, and even can accurately capture the overall variation trends of solar wind parameters during geomagnetic storm. Optimal prediction performance is achieved with a historical input length of 336 hours (corresponding to approximate 14-day quasi-period of the solar wind). The joint modeling prediction based on the inter-parameter dependencies of solar wind parameters is significantly better than the single-parameter prediction. Cross-attention weight analysis reveals that the four solar wind parameters contribute similarly to proton temperature and solar wind speed predictions. The solar wind speed and proton temperature contribute more to the prediction of proton density, while the proton temperature, solar wind speed, and annual time information have a more substantial influence on the prediction of solar wind dynamic pressure. Moreover, the importance of time information grows with increasing scales of time information.

       

    /

    返回文章
    返回