The last few hours have been marked by a question that resonates both in the media and in everyday conversations: what exactly is induced atmospheric vibration and why has it jumped to the forefront of current events? It all stems from the massive blackout that left millions of people without power in Spain and Portugal on April 28, 2025, an unprecedented event that has baffled experts and the general public alike.
The hypothesis of induced atmospheric vibration as the cause of the electrical collapse has generated a great deal of online discussion. However, to what extent is it plausible, what does this physical phenomenon consist of, and what does the scientific community think? Below, we will rigorously and thoroughly examine everything that is known—and what is still up in the air—about this concept and its possible relationship to the Iberian blackout.
The context of the blackout: the version of the electric operators
On April 28, 2025, a sudden power outage plunged much of the Iberian Peninsula into darkness. Immediately, the electricity operators in both countries, REN in Portugal and Red Eléctrica Española (REE) in Spain, activated crisis protocols to try to determine the cause and restore service as quickly as possible.
REN, the Portuguese state-owned company responsible for the electricity transmission network, initially suggested to media outlets such as Reuters and the BBC a possible link to a "rare atmospheric phenomenon" that occurred in Spain. According to them, intense temperature variations may have caused anomalous oscillations in very high voltage (400 kV) lines , a process technically known as induced atmospheric vibration.
Meanwhile, the Spanish government avoided making any definitive statements pending the results of the investigation. The cyberattack theory was mentioned, but without corroborated evidence. Portuguese Prime Minister LuĂs Montenegro himself ruled out malicious intent and reinforced the idea of ​​a natural and highly unusual trigger.
What is atmospheric induced vibration?
The term atmospheric induced vibration describes a physical phenomenon that primarily affects high and very high voltage transmission lines. It consists of the appearance of oscillatory movements in electrical conductors (the overhead cables we see on tall towers), generated by the interaction between electrical factors and external atmospheric conditions.
The process begins when certain weather conditions occur, such as sustained wind, sudden temperature changes, or high humidity. This can lead to what is known in electrical engineering as a corona discharge, which ionizes the air around the conductor and produces small currents between the metal and the atmosphere.
The charged particles thus generated interact with the intense electric field of the high-voltage power lines , giving rise to periodic electrohydrodynamic (EHD) forces. These forces are not strictly mechanical, but rather the result of the interaction between electricity and the atmosphere.
As a result, pressure waves are generated in the surrounding air that directly affect the cable itself . When the frequency of these alternating forces approaches or coincides with the conductor's natural frequency of vibration, the phenomenon of resonance occurs.
This state of resonance can greatly amplify the oscillations of the cable , causing vibrations of considerable amplitude even though wind or temperature conditions appear to be normal at first glance.
How do wind and extreme temperatures affect this phenomenon?
Induced atmospheric vibration is especially likely when two elements come together: constant wind (without sudden gusts or intense turbulence) and unusual temperatures (both high and very low).
Wind can generate pressure vortices around the cable, forcing it to move from side to side. If the speed of these vortices matches the cable's natural vibration frequency (which depends on its length, mass, and tension), intense vibrations can occur.
Extreme temperatures alter the mechanical behavior of conductors . Heat causes cables to expand and become looser, while cold causes them to contract and tighten. Both effects influence their resonant frequency, making them, in many cases, more vulnerable to vibrations caused by wind.
In addition, corona discharge occurs in situations of high humidity or the presence of suspended particles , which facilitates the occurrence of the aforementioned EHD forces.
Differences with other types of vibrations in power lines
In the world of electrical engineering, overhead high-voltage power lines can experience vibrations of very diverse types and origins. It is essential to distinguish induced atmospheric vibration from other similar phenomena that are commonly studied.
- Classical wind vibration: It produces intermediate-frequency oscillations due to the passage of wind. It is usually more predictable and especially affects longer, lower-voltage conductors.
- Gallop: A phenomenon caused by the accumulation of ice or snow on the cable, accompanied by wind. It results in high-amplitude, low-frequency vibrations.
- Induced atmospheric vibration: It is characterized by oscillating at frequencies between 0,1 and 10 Hz, and its main trigger is the combination of particular electrical conditions and atmospheric factors, not just wind.
This difference in origin and mechanism is key to understanding why induced atmospheric vibration is so difficult to predict and mitigate.
Direct and indirect consequences on the electrical system
The repercussions of induced atmospheric vibration can be highly varied and depend on both the intensity and duration of the phenomenon. Although in many cases its effects are limited to audible noise or slight cable displacements, extreme conditions can trigger significant, large-scale problems.
In the long term, repeated exposure to vibrations – even of low amplitude – causes fatigue in the materials that make up the conductors, the insulators and also the hardware that keeps the whole system upright.
This translates into a higher probability of cracks appearing, loosening of connections and accelerated wear at contact points between different elements.
In some cases of particularly intense atmospheric vibrations , automatic protection systems may interpret that there is a serious anomaly and proceed to disconnect entire lines to prevent further damage.
Furthermore, if the vibration disrupts the synchronization of interconnected electrical systems , it can trigger a chain reaction of disconnections or cascading outages, as happened in the great blackout of April 2025, with the fault propagating beyond the initial point.
Why has the official explanation been so controversial?
The attribution of the April 2025 blackout to induced atmospheric vibration has not been without controversy. From the outset, experts in physics, meteorology, and electrical grids have expressed caution regarding the possibility that such a rare phenomenon could cause such a devastating effect.
Some scientists, such as physicist Mario Picazo, emphasized that considerable wind or extreme temperature changes would be necessary to trigger resonances in the electrical grid of the magnitude observed. Although there were significant temperature fluctuations (near-freezing nights followed by highs of 20-25°C), most consider it unlikely that this factor alone would have been enough to cause the collapse.
Other experts, such as JosĂ© MarĂa Madiedo, an astrophysicist at the Institute of Astrophysics of Andalusia, have gone further, ruling out induced atmospheric vibration, triggered by some rare atmospheric phenomenon, as a sufficient explanation . Madiedo proposed the possible impact of a solar event (like the Carrington Event) as an alternative, although the lack of recent solar storms or a simultaneous global impact ruled out this hypothesis.
Network operators and authorities, meanwhile, have remained cautious : while acknowledging the complexity and exceptional nature of the incident, they insist that there is still no conclusive evidence regarding the exact cause. The investigations remain open, and transparency has been key to preventing rumors and speculation.
The recovery process and associated difficulties
Restoring the electricity supply after the blackout of April 28, 2025, has been neither simple nor immediate . The main complication lies in the fact that, as it is an internationally interconnected network (Spain, Portugal, France, and Morocco), any recovery attempt must be gradual and extremely coordinated.
The procedure followed has involved progressively activating key generators in each country to align electricity production with actual user consumption. This "gradual reconnection" is essential to avoid further overloads or desynchronizations that could derail the restoration process.
France, for example, has collaborated by supplying energy to the Spanish grid across the northern border . At the same time, Portugal has disconnected its grid from Spain's to restore normal operations using its own resources and avoid a further domino effect.
In this scenario, the study of sound in space and how vibrations can affect different systems is relevant to understanding the possible causes of the blackout.
In this scenario, resilience and coordination between operators and governments play a fundamental role in restoring stability to the European energy system after an extreme event.
Lessons learned and new challenges for the future
The incident has highlighted several inherent vulnerabilities in current power grids . The pursuit of maximum efficiency through the interconnection of multiple countries and systems has complicated crisis management and recovery after major incidents.
Furthermore, the role of extreme weather events—whether temperature variations, wind, or even solar effects—appears increasingly relevant in the context of climate change . Experts warn that episodes like the recent major Iberian blackout could be repeated if safety protocols, infrastructure maintenance, and monitoring and early warning systems are not updated.
The investigations opened by REN and Red Eléctrica Española seek to understand whether the induced atmospheric vibration was really the "trigger" of the blackout or simply an aggravating circumstance in a particularly delicate network context.
