论文标题
部分可观测时空混沌系统的无模型预测
A Time-Efficient, Data Driven Modelling Approach For Predicting The Geomagnetic Impact of Coronal Mass Ejections
论文作者
论文摘要
为了了解冠状质量弹出（CME）驱动的地磁风暴背后的全球尺度物理过程，并预测它们作为太空天气预测措施的强度，我们使用3D磁含水动力学开发了行径间的CME CME通量 - 磁层相互作用模块。这些模拟充分描述了磁层的ICME效力动力学，包括施加的磁尾扭转。这些相互作用还导致诱导电流，用于计算地磁扰动。通过合适的校准，我们估算了与DST/SYM-H指数相比，GEOOEFFECTIVES-Storm强度指数（Stormi）的代表。由Stormi指数定量的两个对比冠状质量弹出的模拟影响与相应的DST和SYM-H指数具有高线性相关性。我们的方法相对简单，与复杂的流体运动方法相比，要进行微调的参数更少。此外，我们证明了通量绳索侵蚀不会显着影响我们的结果。因此，如果早期预测基于接近点的观测值，我们的方法有可能显着扩展可预测性的时间窗口 - 地理环境预测的挑战 - 在地理环境预测中的出色挑战。这项研究基于CME驱动的地磁风暴的操作预测为早期警告铺平了道路。
To understand the global-scale physical processes behind coronal mass ejection (CME)-driven geomagnetic storms and predict their intensity as a space weather forecasting measure, we develop an interplanetary CME flux rope-magnetosphere interaction module using 3D magnetohydrodynamics. The simulations adequately describe ICME-forced dynamics of the magnetosphere including the imposed magnetotail torsion. These interactions also result in induced currents which is used to calculate the geomagnetic perturbation. Through a suitable calibration, we estimate a proxy of geoeffectiveness -- the Storm Intensity index (STORMI) -- that compares well with the Dst/SYM-H Index. Simulated impacts of two contrasting coronal mass ejections quantified by the STORMI index exhibit a high linear correlation with the corresponding Dst and SYM-H indices. Our approach is relatively simple, has fewer parameters to be fine-tuned, is time-efficient compared to complex fluid-kinetic methods. Furthermore, we demonstrate that flux rope erosion does not significantly affect our results. Thus our method has the potential to significantly extend the time window for predictability -- an outstanding challenge in geospace environment forecasting -- if early predictions of near-Earth CME flux rope structures based on near-Sun observations are available as inputs. This study paves the way for early warnings based on operational predictions of CME-driven geomagnetic storms.
