In this study, we investigated the geomagnetic ground observatory data from 1980 to 2011 collected from World Data Center from 134 stations. To analyze the data we have applied spherical harmonic decomposition to obtain components associated with the Earth’s main magnetic field and to calculate how the Earth’s dipole was varying in the aforementioned recent 31-year period. There is a visible ~ 2.3% decay of the dipole magnetic field of the Earth. We note that the present-day value of the magnetic dipole intensity is the lowest one in the history of modern civilization and that further drop of this value may pose a risk for different domains of our life.

中文翻译：

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地磁场偶极分量最近衰减导致的可能风险

在这项研究中，我们调查了1980年至2011年从世界数据中心的134个站点收集的地磁地面观测数据。为了分析数据，我们应用了球谐分解，以获得与地球主磁场相关的分量，并计算了在最近31年中地球的偶极子如何变化。地球的偶极子磁场有一个可见的〜2.3％衰减。我们注意到，磁偶极子强度的当前值是现代文明史上最低的值，并且该值的进一步下降可能对我们生活的不同领域构成威胁。