A recent study published in the Bulletin of Volcanology has brought fresh insights into the likelihood of an eruption at Mount Teide, Tenerife’s iconic stratovolcano. Teide has long been considered an active yet non-threatening system. However, new seismic activity near Pico Viejo has raised concerns.
The study highlights the importance of continuous monitoring to assess potential risks for the island. The Instituto Geográfico Nacional (IGN) has recently detected increased seismic activity in the Cañadas del Teide area. This has naturally unsettled residents. Similar seismic swarms were recorded before the 2021 eruption of La Palma’s Cumbre Vieja. However, geologists emphasise that these movements could be linked to internal vapor or water interactions rather than magma ascent. Despite this reassurance, experts agree that Teide remains active, warranting further surveillance.
Assessing the probability of eruption
Led by geologist Joan Martí, the study delves into the statistical probability of a Teide eruption within the coming decades. The findings indicate a 2.1% likelihood of a major eruption in the next 20 years, increasing to 5.1% within 50 years and 10% within the next century. Additionally, the probability of a smaller eruption before 2060 stands at 11.1%. Although these figures may seem low, they highlight the necessity for ongoing risk assessment and emergency preparedness.
Past eruptions
Teide’s last recorded eruption took place in 1909. However, the volcano has experienced 16 eruptions over the past 12,000 years. The most powerful eruption occurred 2,020 years ago, reaching a magnitude of 5.3. In 2004, a notable seismic unrest episode prompted closer scrutiny of the volcano. The study warns that long-dormant volcanoes are often underestimated, a mistake that has led to catastrophic consequences in the past.
Experts about recent anomalies
In recent years, and particularly over the past week, Mount Teide has drawn increased attention from both experts and locals. The reason is a series of signs indicating volcanic activity. The scientific team monitoring Teide has detected minor changes, including an increase in carbon dioxide (CO2) emissions and slight ground deformation. However, authorities clarify that there is no immediate or medium-term risk, making it unnecessary to raise the seismic alert level to yellow.
According to Itahiza Domínguez, director of the Instituto Geográfico Nacional (IGN) in the Canary Islands, the current situation differs significantly from the pre-eruption conditions observed in La Palma. He explains that basaltic eruptions, such as those expected from Teide, are usually preceded by intense seismic activity and dense earthquake swarms, none of which have been detected yet.
Since 2016, experts have been tracking a gradual increase in CO2 emissions and microsismic activity. According to Nemesio Pérez, director of the Instituto Volcanológico de Canarias (Involcan), these are “significant changes” which they observed over the past eight years. However, he stresses that they do not necessarily point toward an imminent eruption.
Potential impact on Tenerife
The study outlines possible eruption scenarios. Simulations are suggesting that the caldera of Las Cañadas would shield the island’s southern regions. However, the northeast—home to major cities like Santa Cruz de Tenerife and San Cristóbal de La Laguna—could face higher risks. Scientists identify the northern flanks, particularly the valleys of Icod and La Orotava, as vulnerable areas where lava flows could threaten populated zones.
Possibly nearly one million residents affected
Should an eruption occur, lava could advance over 16 kilometres, potentially reaching the coastline, affecting the livelihoods of nearly one million residents. In addition, pyroclastic flows and gas emissions could impact air quality and infrastructure depending on wind conditions. A Plinian or sub-Plinian eruption could result in widespread ash fallout and toxic gas emissions, making effective disaster preparedness essential.