A long-inactive volcano in northeastern Ethiopia, near the Red Sea coastline, released an unexpected and powerful eruption on November 23, 2025, after thousands of years of silence. The sudden awakening of the Hayli Gubbi volcano in the remote Afar region generated a tall column of ash that rose high into the atmosphere and drifted across several countries. The event drew global attention because the volcano had shown no confirmed eruptions for more than twelve millennia and had remained dormant throughout the Holocene epoch, leading some volcanologists to even regard it as extinct. The scale of the explosion, along with its regional impact and scientific significance, placed the Hayli Gubbi eruption among the most notable recent geological events.
Location and Geological Setting
Hayli Gubbi is situated in northeastern Ethiopia in the Afar region, close to the Eritrean border, within a remote and sparsely populated area. It is a shield volcano forming part of Ethiopia’s East African Rift Zone, near the edge of Danakil desert and the Erta Ale Range. This zone is characterised by the slow separation of the African and Arabian tectonic plates, which move apart by about 0.4 to 0.6 inches every year.
The volcano lies in a landscape shaped by tectonic forces that constantly change the land, creating conditions that could allow magma to accumulate beneath the surface over long periods of time. Earlier satellite data in 2025 revealed magma intrusion beneath the broad ErtaAle volcanic system, including beneath Hayli Gubbi after a July eruption at ErtaAle.
Dormancy and Historical Inactivity
The most striking aspect of the eruption was the long period of inactivity that preceded it. According to the Smithsonian Institution’s Global Volcanism Program, Hayli Gubbi has remained dormant throughout the Holocene epoch, which began approximately 12,000 years ago. This made the eruption extremely rare. Nonetheless, this eruption remains the first documented major eruption of the volcano. Ethiopia has 58 known volcanoes, of which 43 including Hayli Gubbi had no known Holocene eruptions.
Nature of the Eruption
The eruption sent a powerful explosion into the sky and producing thick ash plumes that rose approximately 14 kilometres into the atmosphere. The explosion created a large eruption column, described as a big umbrella cloud, which is considered unusual for a shield volcano, which typically produces fluid lava rather than violent ash-rich explosions when pressure built to critical levels, the magma fragmented into fine ash (tephra), creating an explosive eruption instead of a lava-flow event. The ash clouds drifted across several countries starting from Ethiopia to Yemen, Oman, Pakistan, India, and China. This widespread movement of volcanic ash affected the air quality and raised concerns about possible flight disruptions in areas far beyond Ethiopia. The intensity of the explosion and the height reached by the ash column underscored the force that had built up deep below the surface over thousands of years.
A shield volcano is a broad, gently sloping volcanic landform created by successive eruptions of low viscosity basaltic lava that spreads widely rather than erupting explosively. Owing to the fluid nature of the magma and efficient gas escape, such volcanoes are characterised predominantly by effusive activity and are commonly associated with hotspot regions and divergent plate boundaries, such as the East-African Rift.
Local authorities reported no casualties. However, experts warned that the ash and debris could seriously disrupt life for pastoral communities living in the affected region.
Understanding Dormant Volcanoes
The eruption provided a significant example of the behaviour of dormant volcanoes. A dormant volcano is one that has not erupted for a very long time but still has the potential to become active again. It differs from an extinct volcano, which is considered dead and likely has negligible chances of erupting in the future. Dormant volcanoes could remain quiet for thousands of years without any visible signs of activity. Yet molten rock or magma may still be present beneath the surface and when conditions, such as tectonic movement or an increase in pressure are met, these volcanoes could awaken suddenly.
The event showed that volcanoes considered sleeping could not be ignored, as long intervals of them being quiet do not eliminate the possibility of sudden and powerful activity.
Scientific Observations and Expert Assessments
Experts called the eruption highly unusual. In the era of satellite technology, how the definitive indicators of the Hayli Gubbi’s impending eruption went undetected remains to be determined. Those indicators include the volcanic region’s rising heat levels, small variations observed in the local ground levels and ground uplift caused by accumulating magma pressure, heating up of groundwater, emergence of hot springs and steam near the volcano, and small magma-generated earthquakes, among others.
Juliet Biggs of the University of Bristol noted that in remote volcanic regions such as Afar, the absence of historical records does not necessarily mean the absence of more recent eruptions, as young lava flows may remain undocumented.
Following the eruption, the local residents told reporters that they had noticed faint smoke from the volcano about three days before. However, because the Afar region is remote and understudied, such activity could have gone unnoticed, as there were no reported scientific forecasts for the eruptions.
The eruption demonstrated the importance of continuous observation of volcanic regions, especially those located in geologically active zones. The sudden arrival of a rare eruption column in an area with limited modern eruption history emphasised the need to better understand the internal processes that could accumulate over long periods of dormancy.
Atmospheric and Transboundary Effects
The eruption was a major concern for the aviation sector too. The aircrafts avoided this ash just like the plague. This is so because the volcanic ash particles are extremely abrasive and can clog important sensors. They can impair pneumatics, make the cockpit windscreens opaque, but more critically, they can damage the turbine blades of the aircraft engine and lead to its stalling or flaming out. Along with abrasive particles, the volcanic ash clouds also contain some toxic gases that can potentially enter the aircraft’s ventilation system as well. This could lead to a drop in the cabin’s air quality and could cause respiratory troubles.
The transboundary spread of ash illustrated how volcanic events could influence regions located far from the source. The wide reach of the ash clouds underscored the scale of the eruption and the significant amount of material that the volcano released into the atmosphere. Such movement of ash across countries drew international attention to the event and raised concerns about broader environmental and logistical consequences.
Local Impact and Immediate Response
Despite the strength of the eruption, local authorities reported no casualties. This was significant because the explosion occurred in a region with pastoral communities whose livelihoods depend on grazing lands. Ash fallout and debris could damage livestock, contaminate water sources, and disrupt daily life. Experts noted that even in the absence of immediate casualties, the long-term effects on local communities could be serious.
The eruption also demonstrated the importance of monitoring and preparedness in remote regions. The lack of prior signs and the long dormancy of the volcano meant that the event came without any warning. Although the absence of casualties indicated that immediate harm was avoided, the aftermath required assessment to understand how ash and debris might affect the region in the days following the eruption.
Significance of the Eruption for Volcanology
The Hayli Gubbi eruption became an important event for volcanology because it provided a rare opportunity to study how volcanoes with long dormancy periods have. It challenged assumptions about which volcanoes are ‘extinct’ versus ‘dormant’, demonstrated that shield volcanoes can produce explosive eruptions, and underscored the limitations of monitoring in remote tectonic regions.
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