A study conducted by researchers at INGV suggests the use of thermal data from the International Space Station in seismic alerting of the Phlegraean area
The Campi Flegrei are one of the most active volcanic areas in the world and, in recent years, their seismicity has increased significantly. A study of the National Institute of Geophysics and Volcanology (INGV), published in the magazine Remote Sensing Letters It is entitled “A novel algorithm for thermal monitoring using ECOSTRESS time series: the case of Campi Flegrei, Naples, Italy”, described a method of analysis of thermal images taken by the International Space Station (ISS) capable of detecting significant temperature variations that precede the most intense earthquakes in the Phlegraean area.
The method uses the data collected by the tool ECOSTRESS, a NASA-JPL sensor installed on the ISS, which estimates surface temperature with a high spatial resolution of about 70 m and frequent passes over the same area around three days. Scientists have generated two historical temperature series extracted from thermal images of two areas of the Solfatara between 2021 and 2024The temperature difference between the two areas was analyzed with two distinct statistical methods, allowing the detected anomalies to be compared with the main seismic events recorded in the area.
"We have detected anomalous temperature variations in the Solfatara emission zone that preceded some earthquakes of greater intensity, with an advance ranging from a few days to a few weeks", explains Alexander Piscini, researcher at INGV and first author of the article.
For example, on May 17, 2024, a temperature increase of 5°C anticipated the magnitude 4.4 earthquake by three days. For the magnitude 4.2 event on September 27, 2023, the temperature increase observed on September 21 exceeded 7°C. The second statistical method also highlighted temperature anomalies for these two events that appeared on April 12, 2024 and September 6, 2023, respectively. Furthermore, the average value of the temperature difference has increased in recent years, consistently with the increase in other signals already observed in the area, such as ground rise (bradyseism) and carbon dioxide emissions.
“The temperature anomalies highlighted through two different statistical analyses make us more confident about the possible link between the surface temperature fluctuation and the seismic activity of the area”, says Christian Fidani, INGV researcher and co-author of the research.
