近日，美国天主教大学Nithin Sivadas团队揭示了回归均值可以解释地磁风暴的饱和现象。2026年7月15日出版的《自然》杂志发表了这项成果。

极端空间天气事件发生在太阳风强驱动期间。太阳风驱动近地空间环境中的等离子体对流和电流。在驱动因子较低时，地球的响应是线性的，可通过基于地面磁力计活动的极盖指数等参数来估算。奇怪的是，在极端太阳风驱动下，地球的响应似乎不会超过某个饱和极限。理论学家对此饱和效应提出了多种解释，但尚未达成共识。

研究组证明，这种饱和是均值回归效应的一种表现，源于太阳风测量在时间和幅度上的随机不确定性。该结果表明，支撑饱和理论的数据分析存在非线性偏差，从而对这些理论的有效性提出了挑战。校正不确定性后显示，地球对太阳风驱动的响应始终是线性的，极端地磁暴的影响可能是此前认为的两倍。研究组表明，均值回归是测量值与真实值之间关系的基本属性，即测量值对应的真实值更接近平均值。这种效应在极端值的不确定测量中尤为显著，并可能在从极端气候研究到慢性医学疼痛等各个领域中均有体现。

附：英文原文

Title: Regression to the mean can explain saturation of geomagnetic storms

Author: Sivadas, Nithin, Sibeck, David, Subramanyan, Varsha, Walach, Maria-Theresia, Ozturk, Dogacan Su, Ferdousi, Banafsheh, Michotte de Welle, Bayane

Issue&Volume: 2026-07-15

Abstract: Extreme space weather events on Earth occur during intervals of strong solar wind driving1. The solar wind drives plasma convection and currents in the near-Earth space environment2. For low values of the driver, the Earth’s response is linear, estimated by parameters such as the polar cap index based on ground magnetometer activity3. Curiously, for extreme solar wind driving, the Earth’s response appears not to increase beyond a saturation limit4. Theorists have advanced a host of explanations for this saturation effect, but there is no consensus5. Here we demonstrate that this saturation is a manifestation of the regression to the mean effect6 arising from random uncertainty in the timing and magnitude of solar wind measurements. Our results reveal that data analysis underpinning the saturation theories is nonlinearly biased, thereby challenging the validity of the theories. Correcting for the uncertainties reveals that the Earth’s response to solar wind driving is linear throughout, and that the impact of extreme geomagnetic storms can be twice as large as previously thought. We show that regression to the mean is a fundamental property of the relationship between measurement and the truth, where the truth corresponding to the measurement is closer to the mean. This effect is particularly pronounced for uncertain measurements of extreme values and is likely to manifest across various fields, from extreme climate studies to chronic medical pain.

DOI: 10.1038/s41586-026-10757-4

Source: https://www.nature.com/articles/s41586-026-10757-4

期刊信息

Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504

官方网址：http://www.nature.com/

投稿链接：http://www.nature.com/authors/submit_manuscript.html