Faint crater glow at Kanlaon may signal volcanic activity – Phivolcs

A faint crater glow was detected at Kanlaon Volcano's summit on June 29, 2026, marking another instance of unusual volcanic activity in the region. The glow, which lasted between 3:40 a.m. and 4:30 a.m., was observed by the Philippine Institute of Volcanology and Seismology (Phivolcs). This phenomenon, known locally as "banaag," is caused by superheated volcanic gases escaping from the crater, producing a visible red light. According to Phivolcs, such occurrences are often linked to magma rising closer to the surface, potentially signaling increased volcanic unrest.

The observation comes just months after a similar event took place in May 2026, where a crater glow persisted for two to three days before subsiding. That incident had already raised concerns among scientists about the potential for future eruptions. At that time, Phivolcs maintained Kanlaon’s alert level at 2, indicating that the volcano was exhibiting signs of unrest but was not currently erupting. The recurrence of the glow suggests that the volcano remains active and warrants continued monitoring.

Kanlaon Volcano, located on Negros Island, is one of the most active volcanoes in the Philippines. It has erupted several times over the past century, with notable eruptions occurring in 1972, 1996, and more recently in 2015. These eruptions have prompted evacuations and disrupted local communities, highlighting the importance of ongoing surveillance and preparedness measures. The recent detection of a crater glow adds to the list of indicators that scientists use to assess the likelihood of an impending eruption.

Mari-Andylene Quintia, a resident volcanologist at Phivolcs, emphasized that while the presence of a crater glow can be concerning, it does not necessarily mean an immediate eruption is imminent. She noted that the phenomenon could serve as a precursor to either an explosive or magmatic eruption, depending on how the magma behaves beneath the surface. However, she also cautioned that it is still too early to make definitive predictions about the volcano’s behavior.

Phivolcs has stated that it will continue to monitor Kanlaon closely using a range of instruments, including seismometers, tiltmeters, and gas sensors. These tools help detect changes in seismic activity, ground deformation, and gas emissions—key indicators of volcanic unrest. If the crater glow persists or becomes more intense, Phivolcs may consider raising the volcano’s alert level beyond its current status of 2. Such a decision would involve careful analysis of additional data and consultations with other experts in the field.

Local authorities and residents near Kanlaon have been advised to remain vigilant and follow updates from Phivolcs. While there is no immediate threat, the possibility of an eruption means that emergency preparedness plans must remain in place. Communities living in areas prone to volcanic hazards are encouraged to stay informed and ready to respond should conditions change rapidly.

As of now, the situation remains under close watch, with scientists working diligently to gather more information about the volcano’s current state. The recurrence of the crater glow underscores the need for continuous monitoring and highlights the unpredictable nature of volcanic systems. Although the exact timing and scale of any potential eruption remain uncertain, the observations made so far provide valuable insights into the dynamics of Kanlaon Volcano.

In the coming weeks, further developments will depend on how the volcano behaves. If new data emerges suggesting a higher risk of an eruption, Phivolcs will likely take appropriate action to ensure public safety. For now, the focus remains on gathering more evidence and maintaining a high level of vigilance.