Beneath our feet, colossal forces pulse silently, reminding us that earthly stability is a fleeting illusion. Supervolcanoes represent the most extreme form of volcanic activity, capable of transforming the climate and testing the resilience of human civilization in a matter of days. Although they often go unnoticed, scientific advances have brought these formations into sharp focus, particularly in regions such as Yellowstone in the United States and the Phlegraean Fields in Italy.
The concern of the geological community is not unfounded: the reactivation of one of these giants would mean disturbances on a global scale, from prolonged darkness caused by ash to extensive losses in biodiversity and the economy. However, science still lacks a foolproof formula for predicting when the next major eruption will occur.
What distinguishes supervolcanoes?
Supervolcanoes and conventional volcanoes are similar in essence, but differ radically in magnitude. While an ordinary volcano can eject tens of millions of cubic meters of material, a supervolcano has the capacity to release more than 1.000 cubic kilometers of ash and lava at once. Such an explosion can create giant depressions in the ground, called calderas, and change the environment for centuries.
The most notable effects of a major eruption include: reduction of solar radiation –causing the so-called volcanic winter–, serious impacts on agriculture and human health, and profound alterations to global ecosystems. The atmosphere could remain laden with particles for years, altering rainfall and temperature patterns across the planet.
Phlegraean Fields: a natural laboratory under surveillance
In southern Italy, the Phlegraean Fields They challenge the tranquility of Naples. This vast volcanic structure, made up of various calderas and craters, is among the most closely monitored in the world. The region experiences constant hydrothermal activity, releasing gases and vapors that show the presence of magma beneath the surface.
Recently, several shallow earthquakes have shaken the area, with significant magnitudes that have even forced the preventive suspension of rail services. Experts from the National Institute of Geophysics and Volcanology (INGV) link this seismic activity to the phenomenon of bradysm, the gradual uplift of the ground caused by the accumulation of gases and magma in the depths.
Authorities insist there is no sign of an imminent eruption, but the constant monitoring is key to manage risks in a region so densely populated and with a history of volcanic catastrophes.
Yellowstone: Sleeping Giant or Latent Threat?
In the United States, the gaze is directed towards yellowstone supervolcano, a colossus whose caldera spans several states and whose geological history is marked by three super-eruptions in the last 2,1 million years. Recent research has revealed that the magma chamber beneath Yellowstone is much more active than previously thought., with magma pockets occupying up to 30% of its volume under the main caldera.
USGS specialists have generated three-dimensional maps of the area, revealing a buildup of sticky magma beneath northeast Yellowstone National Park. This discovery, which exceeds the volume ejected in past eruptions, was made possible through the use of advanced electrical measurement and machine learning techniques, identifying ten times more earthquakes between 2008 and 2022 than previously recorded.
Among the factors that concern scientists are frequent seismic swarms and ground deformations, both associated with underground magmatic movements. However, according to the National Park Service and independent biologists, The recent movements of animals in the area have normal migratory explanations, far from a catastrophic omen.
Consequences of a supereruption
In the hypothetical case that one of these supervolcanoes awakens, the effects will be felt all over the worldA Yellowstone eruption, for example, would begin with a violent explosion, followed by columns of ash rising into the stratosphere and pyroclastic clouds sweeping across hundreds of miles.
Ash would cover much of North America in a matter of hours, crippling power grids, contaminating water, and paralyzing ground and air transportation. Remote cities like Chicago, San Francisco, and even New York would receive a significant layer of ash, with nearby areas completely devastated. The agricultural and health consequences would be immediate., with massive crop failure and widespread respiratory problems.
In addition, the blocking of sunlight after the eruption would cause a global drop in temperatures. The so-called volcanic winter could last for several years, affecting food production and triggering economic and social crises on a global scale.
Are we prepared for the awakening of a supervolcano?
Despite advances in monitoring and prediction, Uncertainty remains the norm in supervolcano monitoringAlthough scientists hope to detect early warning signs such as changes in seismic activity, ground deformations, and chemical alterations in gases, recent studies at Yellowstone and other supervolcanoes suggest that the signs may be minimal or too late for effective evacuation.
What is clear is that Prevention and constant research are essential to mitigate potential damage. Scientific projects in Yellowstone have fine-tuned early warning systems and guided the safe use of geothermal energy, but the unpredictable nature of these giants requires preparation for any scenario.