New “Jerk” Signal Could Predict Volcanic Eruptions Hours Before They Happen

Scientists may be closer than ever to accurately predicting volcanic eruptions, thanks to the discovery of a subtle geophysical signal known as “jerk,” which can reveal magma movement hours before an eruption begins. The finding, published in Nature Communications, December 2025 offers a simpler and potentially more reliable method for early warning, addressing one of the most persistent challenges in volcanology.

For decades, predicting volcanic eruptions has relied on interpreting a combination of warning signs, including earthquakes, ground deformation, and gas emissions. While these indicators provide valuable clues, they often produce complex and sometimes conflicting data, making it difficult for scientists to determine exactly when an eruption will occur. This uncertainty can have serious consequences, from delayed evacuations to costly false alarms that undermine public trust.

The newly identified “jerk” signal takes a different approach by focusing on extremely slow, low-frequency ground movements caused by magma pushing through the Earth’s crust. These movements are so subtle that they can easily go unnoticed, yet they carry critical information about what is happening beneath the surface. As magma rises, it forces surrounding rock to fracture, producing a distinct signal that reflects the physical processes leading directly to an eruption.

Researchers say this is what makes the method particularly promising. Instead of relying on indirect indicators, the “jerk” signal is tied directly to the mechanics of magma intrusion. “These faint signals can reveal the earliest stages of volcanic activity in real time,” the research team noted, emphasizing the potential for more precise forecasting.

How Accurate Is This New Eruption Prediction Method?

The method was rigorously tested at Piton de la Fournaise, one of the most active volcanoes in the world, located on La Réunion Island. Over a period spanning nearly a decade, from 2014 to 2023, the system demonstrated remarkable accuracy. It successfully predicted 92 percent of eruptions, with warning times ranging from just a few minutes to more than eight hours before magma reached the surface.

Such performance is significant in a field where eruption forecasting is often fraught with uncertainty. In many cases, scientists are only able to identify eruption precursors after the event has already occurred. According to co-author, Philippe Jousset, this study stands out because it tested the method in real time over an extended period. “In a majority of studies, eruption precursors are identified after the fact,” he said. “The originality of this work is that the method was tested and validated in real time for more than 10 years.”

The system operates automatically, issuing alerts once the signal reaches a certain threshold, reducing the need for complex human interpretation and enabling faster response times.

Why Is Predicting Volcanic Eruptions So Difficult?

One of the biggest challenges in volcanology is distinguishing between signals that lead to eruptions and those that do not. Volcanoes often show signs of unrest that never result in an eruption, making it difficult for scientists to issue clear warnings.

Traditional monitoring systems rely on multiple datasets that must be interpreted together, which increases uncertainty. Conflicting signals can lead to hesitation or misjudgment, particularly in high-risk situations where decisions must be made quickly.

The “jerk” signal addresses this problem by focusing on a single, physically meaningful indicator directly linked to magma movement. This simplifies interpretation and may improve confidence in eruption forecasts.

Can the “Jerk” Signal Reduce False Alarms?

Despite its strong performance, the system is not without limitations. During the testing period, about 14 percent of alerts did not lead to eruptions. However, researchers argue that these should not be considered false alarms in the traditional sense.

Instead, they correspond to real magma movements that did not reach the surface, sometimes referred to as aborted eruptions. In this context, the signal is still capturing meaningful geological activity beneath the volcano.

“In addition to predicting eruptions, the tool is a clear detector of magmatic intrusions,” Jousset explained. This means that even when an eruption does not occur, the system is still providing valuable insight into subsurface processes.

Can This Technology Be Used Worldwide?

Another key advantage of the “jerk” signal is its simplicity. Traditional volcano monitoring systems typically rely on networks of instruments that measure different parameters, requiring significant resources to install and maintain.

In contrast, the “jerk” signal can be detected using a single broadband seismometer. This reduces both the technical complexity and cost of monitoring, potentially making it accessible for use in remote or under-monitored regions.

This simplicity could have far-reaching implications. Many volcanoes around the world lack comprehensive monitoring systems, leaving nearby communities vulnerable to sudden eruptions. By lowering the barrier to effective monitoring, the new method could help expand early warning capabilities to areas that need them most.

What Happens Next for Volcano Early Warning Systems?

Researchers are now working to determine whether the method can be applied to other volcanoes with different geological characteristics. Initial efforts include testing the system at Mount Etna in Italy, one of Europe’s most active volcanoes.

If the results prove consistent, the “jerk” signal could become a standard component of volcano monitoring systems worldwide. Integrating this method with existing technologies may further enhance the accuracy and reliability of eruption forecasts.

Why This Discovery Matters for Disaster Preparedness

The implications for disaster preparedness are significant. Earlier and more reliable warnings could provide communities with crucial time to evacuate, secure infrastructure, and minimize economic losses.

At the same time, reducing uncertainty in forecasts could help authorities avoid unnecessary evacuations, which can be disruptive and costly. Improved accuracy may also strengthen public trust in early warning systems, encouraging faster and more effective responses.

Ultimately, the discovery of the “jerk” signal represents a promising step forward in the effort to better understand and predict volcanic eruptions. By capturing the subtle movements that occur just before an eruption, scientists are gaining a clearer picture of the processes unfolding beneath the Earth’s surface.

While further research is needed to confirm its effectiveness across different environments, the method offers a compelling new tool in the quest for accurate and timely eruption forecasts. For communities living in the shadow of active volcanoes, that progress could make a critical difference, turning uncertainty into actionable warning and helping to reduce the risks posed by one of nature’s most powerful forces. (Sulung Prasetyo)