Solar physicists and seismologists are testing a provocative idea: that violent outbursts from the Sun could be linked to the timing of some large earthquakes. New statistical work reports correlations between geomagnetic storms that follow solar eruptions and a higher chance of strong quakes, while other researchers argue those links vanish once natural cycles are properly modeled. The debate matters as solar activity ramps up and quake-prone regions weigh how much attention to pay to space weather.
At stake is whether solar flares and related storms simply threaten satellites and power grids, or whether they also interact with the stressed rocks beneath people’s feet. If even a small fraction of major earthquakes were influenced by solar activity, that could change how hazard planners think about timing, risk clustering, and early warning. It also raises questions about how to interpret statistical patterns that appear across very different datasets, from space-weather indices to global seismic catalogs.
What solar storms actually do to Earth
Solar flares are sudden bursts of radiation from the Sun, often linked to eruptions of plasma called coronal mass ejections that can drive geomagnetic storms around Earth, according to a NASA overview. Those storms disturb the planet’s magnetosphere and ionosphere and can disrupt power grids, radio communications, satellites, and create auroras, according to a NOAA explainer. NASA classifies flares from weak A- and B-class events up through powerful X-class bursts, with the strongest X flares capable of triggering intense space-weather effects when paired with Earth-directed eruptions.
These storms do not just stay in space. Geomagnetic disturbances generate electric fields and currents in the ground, according to a USGS fact sheet on solar-cycle variability and geoelectric hazards. Those induced currents can affect infrastructure such as power grids, and geomagnetic storms generate electrical currents in Earth that can be modeled for near-real-time hazard analysis, according to a related USGS release describing the USMTArray survey. That established electrical coupling between space weather and the solid Earth is one reason some scientists are asking whether the same currents might also influence faults that are already close to failure.
Studies that find solar–seismic correlations
One peer-reviewed analysis in Geophysical Research Letters reports statistically significant correlations between intense geomagnetic storms and an increased likelihood of global strong earthquakes, according to the AGU paper. The authors identify specific time lags in the data, including intervals around 27 to 28 days, which corresponds to the approximate rotation period of the Sun as active regions swing back into view. In their approach, geomagnetic storms serve as a proxy for solar activity, and the team then looks for systematic changes in the rate of strong earthquakes in the days and weeks that follow those storms.
A separate preprint on arXiv reports a high-significance statistical correlation between solar-wind proton density and velocity and global large earthquakes defined as magnitude greater than 5.8. In that analysis, the strongest signal appears with a lag of about one day between peaks in solar-wind parameters and the occurrence of these M>5.8 events, suggesting a relatively prompt response. The authors go further by proposing a mechanism involving an electrically induced effect such as a reverse piezoelectric response inside stressed rocks, arguing that changing electromagnetic fields might slightly alter stress conditions along faults that are already near their breaking point.
Research that says the signal disappears
Not all statisticians are convinced the apparent links are real. A contrarian primary analysis published in the journal Atmosphere argues that apparent pre-earthquake anomalies in solar and geomagnetic indices can be statistical artifacts once natural cycles and simulations are properly accounted for, according to the Atmosphere study. That analysis uses synthetic catalogs and randomized time series to show that when repeating cycles and random clustering are included, patterns that look meaningful can arise by chance, especially when researchers search across many different time lags and thresholds.
After running its own tests, the Atmosphere work concludes there is no significant correlation between solar or geomagnetic activity and strong earthquakes in its sample. That conclusion aligns with the U.S. Geological Survey’s position that there is no proven causal link between solar flares or magnetic storms and earthquakes, according to a USGS space-weather FAQ. Together, those institutional positions highlight a gap between intriguing correlations in some datasets and the higher bar of reproducible, mechanism-backed causation that would be needed before space weather could factor into operational earthquake forecasting.
How a solar flare might jolt a fault
To bridge that gap, some researchers are looking at how electromagnetic energy moves from the Sun into the ground, and how that energy might interact with stressed crust. Solar events affect Earth’s magnetosphere and ionosphere, and solar drivers of geomagnetic storms include coronal mass ejections and high-speed streams, with physical conditions such as southward interplanetary magnetic field and sustained high-speed wind making storms more geoeffective, according to the NOAA discussion. Solar-cycle variability and geomagnetic storms then create geoelectric hazards through induced currents that affect infrastructure on Earth, according to the USGS summary, which also notes that geomagnetic disturbances generate electric fields and currents in the ground that depend on local geology.
The arXiv preprint proposing a one-day lag suggests that these induced fields could interact with stressed crust through an electrically induced effect such as reverse piezoelectric behavior, in which changing electric fields alter mechanical stresses in certain minerals. A separate study of sunquakes, which are acoustic waves triggered inside the Sun by strong flares, notes that the origin of those sunquakes has been controversial and that several categories of driving mechanisms have been proposed, including energy deposition by highly energetic electrons, according to research on flare-accelerated particles. That ongoing solar-side debate about how flares shake their own star underscores how complex it is to pin down physical mechanisms, even before trying to extend them to Earth’s crust and its network of faults.
Why quake belts, data networks, and open archives matter
Any solar trigger, if it exists, would act on a planet where tectonics already concentrate risk. The Ring of Fire, also called the Circum-Pacific belt, is the zone of earthquakes surrounding the Pacific Ocean where about 90% of the world’s earthquakes occur, according to USGS cool earthquake facts. That concentration means even a subtle external nudge, if real, could have outsized human consequences in regions already primed for large ruptures. It also means that distinguishing any solar influence from the background rhythm of plate tectonics requires dense seismic networks and long, carefully curated catalogs.
On the space-weather side, researchers rely on continuous monitoring of the Sun and solar wind, coupled with archives that make it possible to test new hypotheses. Preprint servers play a visible role in this debate: the solar–seismic correlation study appears on arXiv, which is supported by institutional members listed on its membership page and by individual contributors who use the platform’s donation portal. Guidance on how authors submit, revise, and share their manuscripts is laid out in arXiv’s help resources, which emphasize that preprints are not peer-reviewed even when they circulate widely. As solar activity increases and major earthquakes continue to strike along the world’s active belts, that mix of open archives, formal journals, and public data will shape how quickly the scientific community can confirm or dismiss whether space-weather conditions are sometimes associated with the timing of earthquakes.
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*This article was researched with the help of AI, with human editors creating the final content.
