For decades, seismologists have worked to understand and predict earthquakes, but forecasting remains elusive. Now, scientists are investigating an intriguing link between solar activity and seismic events.

Using advanced models, researchers found that fluctuations in solar heat impact Earth’s surface temperature, potentially affecting tectonic movements. This effect, while not the primary cause of earthquakes, could improve prediction accuracy. If refined, this method might one day offer crucial warnings, helping to save lives before disaster strikes.

Understanding Earthquake Mechanics

Seismologists understand the fundamental mechanics of earthquakes: as tectonic plates shift, they build up strain energy that eventually releases, triggering seismic events. However, accurately forecasting earthquakes remains a major challenge. Without reliable predictions, cities remain vulnerable to disasters like the 2011 magnitude 9.0 Tōhoku earthquake, which caused a devastating tsunami and the Fukushima nuclear crisis, resulting in over 18,000 deaths.

Recent research has explored whether the sun or moon might influence seismic activity. Some studies suggest that tidal forces or electromagnetic effects could interact with the Earth’s crust, core, and mantle, potentially playing a role in earthquake patterns.

Investigating the Role of Solar Heat

A new study published today (March 4) in Chaos by AIP Publishing, led by researchers from the University of Tsukuba and the National Institute of Advanced Industrial Science and Technology in Japan, investigates whether Earth’s climate — particularly temperature changes driven by solar heat — affects earthquake activity. This builds on their previous 2022 study, which found a connection between sunspot activity and seismic patterns, suggesting a possible causal link.

“Solar heat drives atmospheric temperature changes, which in turn can affect things like rock properties and underground water movement,” said author Matheus Henrique Junqueira Saldanha. “Such fluctuations can make rocks more brittle and prone to fracturing, for example — and changes in rainfall and snowmelt can alter the pressure on tectonic plate boundaries. While these factors may not be the main drivers of earthquakes, they could still be playing a role that can help to predict seismic activity.”

A Data-Driven Approach to Forecasting

Using mathematical and computational methods, the researchers analyzed earthquake data alongside solar activity records and surface temperatures on Earth. Among other findings, they observed that when they included Earth surface temperatures into their model, the forecasting became more accurate, especially for shallow earthquakes.

“That makes sense, since heat and water mostly affect the upper layers of the Earth’s crust,” said Junqueira Saldanha.

Toward a New Earthquake Prediction Model

The findings suggest the transfer of solar heat to the surface of the Earth does affect seismic activity, however minutely, and that incorporating solar activity predictions into detailed Earth temperature models may help issue earthquake forecasts.

“It’s an exciting direction, and we hope our study sheds some light on the bigger picture of what triggers earthquakes,” said Junqueira Saldanha.

Reference: “The role of solar heat in earthquake activity” is authored by Matheus Henrique Junqueira Saldanha, Masanori Shiro, Yuji Yagi, and Yoshito Hirata, 4 March 2025, Chaos An Interdisciplinary Journal of Nonlinear Science.
DOI: 10.1063/5.0243721