Both solar activities from above and perturbations of Earth’s surface and troposphere from below disturb ionospheric structure and its dynamics. Numerous ionospheric phenomena remain unexplained due to the complicated nature of the solar–terrestrial environment. We do appreciate the ground- and space-based Global Navigation Satellite System (GNSS) techniques being around and providing global observations with high resolutions to help us to resolve unexplained phenomena. This paper summarizes recent studies of the effect of solar (geomagnetic storm and total solar eclipse), tropospheric (typhoon, walker circulation, and El Niño-Southern Oscillation), and earthquake/tsunami activities (2010 Chile, 2011 Tohoku, and 2015 Nepal earthquakes) on the ionosphere utilizing the global ground- and space-based GNSS observations.

中文翻译：

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GNSS使我们从电离层重新回到地面

来自上方的太阳活动以及来自下方的地球表面和对流层的扰动都会干扰电离层结构及其动力学。由于日地环境的复杂性，许多电离层现象仍然无法解释。我们确实感谢周围的地面和空基全球导航卫星系统（GNSS）技术并提供高分辨率的全球观测资料，以帮助我们解决无法解释的现象。本文总结了有关太阳（地磁风暴和日全食），对流层（台风，沃克环流和厄尔尼诺-南方涛动）以及地震/海啸活动（2010年智利，2011年东北和2015年尼泊尔地震）影响的最新研究。电离层），利用全球地面和空间GNSS观测资料。