Science News from research organizations Scientists just discovered a tiny signal that volcanoes send before they erupt Scientists have developed a simple new “Jerk” signal detector that can warn of volcanic eruptions hours before they happen. Date: March 15, 2026 Source: GFZ Helmholtz-Zentrum für Geoforschung Summary: A new detection method called “Jerk” could dramatically improve how scientists forecast volcanic eruptions. By using a single broadband seismometer, the system can detect extremely subtle ground movements caused by magma pushing underground—often hours before an eruption begins. Tested for more than a decade at the Piton de la Fournaise volcano on La Réunion, the tool successfully predicted 92% of eruptions between 2014 and 2023, sometimes giving up to eight hours of warning. Share: Facebook Twitter Pinterest LinkedIN Email FULL STORY A new method called “Jerk” can detect incredibly subtle ground movements caused by rising magma, offering early warnings of volcanic eruptions. In a decade-long test, it successfully predicted 92% of eruptions at one of the world’s most active volcanoes. Credit: Shutterstock Predicting volcanic eruptions early enough to warn authorities and nearby communities remains one of the biggest challenges in volcanology. A study published in Nature Communications describes a new detection technique called "Jerk," developed by researchers and engineers from the Institut de Physique du Globe de Paris (IPGP) and the GFZ Helmholtz Centre for Geosciences. The method relies on a single broadband seismometer to detect extremely subtle ground movements linked to magma intrusions deep underground. These faint signals can reveal the earliest stages of volcanic activity in real time. The research team tested the method for ten years at a volcanological observatory on the island of La Réunion. During that period, the system successfully forecast 92 % of the 24 eruptions that occurred between 2014 and 2023. Warning times ranged from just a few minutes to as much as eight hours before an eruption began. About 14 % of the alerts did not result in eruptions. However, those alerts still detected magma movements beneath the volcano. Because it requires relatively little equipment, the Jerk system could become an important early warning tool, particularly for volcanoes that are not closely monitored. Why Predicting Volcano Eruptions Is Difficult Volcanoes often show warning signs before erupting. These may include increased seismic activity, deformation of the ground, and changes in volcanic gas emissions or composition. While these signals are well known, accurately interpreting them remains difficult. Scientists still struggle to determine exactly when an eruption will occur, how long it will last, and how powerful it might be. False alarms also pose a serious problem. Incorrect warnings can cause costly evacuations, economic disruption, and public distrust of monitoring systems. As a result, improving the reliability of eruption forecasts is a major goal for scientists studying volcanic hazards. Detecting Subtle Ground Motion From Rising Magma Many previous approaches to eruption forecasting rely on probabilistic analysis, meaning they search for statistical relationships in large sets of monitoring data. In contrast, the new approach developed by a team led by Dr. François Beauducel from the Institut de Physique du Globe de Paris and Dr. Philippe Jousset from the GFZ Helmholtz Centre for GeoResearch in Potsdam focuses on directly detecting physical signals associated with magma movement. The "Jerk" method identifies extremely small ground motions that occur when magma intrudes into the crust. These signals appear as very low frequency transients i.e. impulse like transition or settling signals recorded in horizontal ground motion, including both acceleration and tilt. According to the researchers, these signals likely originate from dynamic rock fracturing processes that take place before an eruption. Scientists first identified these signals more than a decade ago while analyzing extensive datasets from previous eruptions of the Piton de la Fournaise volcano on La Réunion. The signals are extraordinarily small, measuring only a few nanometers per second cubed (nm/s 3 ). Even so, they can be detected with a single very broadband seismometer. The system includes specialized data processing that i.e. corrects for factors such as Earth tides. When the characteristic signal exceeds a certain threshold, the automated system immediately issues an alert. A Decade of Real Time Volcano Monitoring The system was installed in April 2014 at the Piton de la Fournaise volcanological observatory operated by the Institut de Physique du Globe de Paris (IPGP) of the Université Cité Paris (OVPF-IPGP, Reunion Island). The tool functions as an automated component of the WebObs monitoring system and uses data from a broadband seismological station belon