Abstract Multiple properties of the solar wind that affect the earth are summarized in this overview. 13 specific solar-wind parameters that influence geomagnetic activity, the plasma sheet, the ionosphere, and the electron radiation belt are catalogued: these include the wind speed, number density, magnetic-field strength, field orientation, Mach number, Alfven speed, electron-strahl intensity, and magnetic-field fluctuation amplitude. The solar wind at Earth is categorized into four types of plasma emanating from different morphological features on the solar surface and the systematic differences between the four plasma types is assessed. The solar-cycle behavior of the solar wind is examined in terms of the changing occurrence rates of the four plasma types emanating from the changing Sun. A 27-day periodicity in the properties of the solar wind and in the reaction of the Earth are investigated: the periodicity is owed to features on the rotating Sun. The strong intercorrelations between solar-wind variables are considered and the origins of the intercorrelations are explained. Large-scale structures in the solar wind are reviewed and the different types of geomagnetic storms that they drive are summarized. The mesoscale magnetic structure of the solar wind is examined, the impact on Earth of its current sheets and cellular structure is explored, and a non-randomness in variations of the magnetic-field direction changes at Earth is demonstrated. Sudden strong velocity shears in the solar wind are discussed and their impact on the magnetosphere is shown via a global MHD simulation. The magnetic structure moving outward from the Sun faster than the plasma outflow is discussed, and it is pointed out that the velocity of the magnetic structure should be used when calculating the motional electric field of the Sun. Finally, drawbacks to monitoring the solar wind from L1 are identified.

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关于太阳风，磁层和电离层研究人员应该了解什么

摘要 本综述总结了影响地球的太阳风的多种特性。对影响地磁活动、等离子层、电离层和电子辐射带的 13 个特定太阳风参数进行了编目：这些参数包括风速、数密度、磁场强度、磁场方向、马赫数、阿尔文速度、电子-strahl 强度和磁场波动幅度。根据太阳表面不同的形态特征，地球上的太阳风被分为四种类型的等离子体，并评估了四种等离子体类型之间的系统差异。太阳风的太阳周期行为是根据不断变化的太阳发出的四种等离子体类型的变化发生率来检查的。对太阳风特性和地球反应的 27 天周期性进行了研究：这种周期性是由于太阳旋转的特征造成的。考虑了太阳风变量之间的强相关性，并解释了相关性的起源。回顾了太阳风中的大型结构，并总结了它们驱动的不同类型的地磁暴。研究了太阳风的中尺度磁结构，探索了其电流片和细胞结构对地球的影响，并证明了地球磁场方向变化的非随机性变化。讨论了太阳风中突然的强速度切变，并通过全球 MHD 模拟显示了它们对磁层的影响。讨论了从太阳向外移动的磁结构比等离子体流出速度更快，并指出在计算太阳的运动电场时应使用磁结构的速度。最后，确定了从 L1 监测太阳风的缺点。