The lower sulfur emissions from Kanlaon Volcano may indicate a slower movement of magma beneath its surface.
From 18-24 February, the Philippine Institute of Volcanology and Seismology (Phivolcs) recorded an average of at least 2,800 tonnes of sulfur dioxide emissions from the volcano. The highest recorded release was on 18 February, with 4,685 tonnes, while the lowest was on 21 February, with 1,542 tonnes.
The week-long sulfur dioxide emissions were lower than earlier levels, particularly in January, when the daily average reached at least 5,000 tonnes.
In a phone interview, Phivolcs Senior Science Research Specialist Paul Alanis said several factors could explain the decrease in Kanlaon’s sulfur emissions.
“The trends indicate a decline in sulfur dioxide, which could mean that magma movement might be slowing down,” Alanis said, noting that despite the week-long decrease, the overall average still ranges around 4,000 tonnes.
Alanis also noted that excessively low sulfur dioxide emissions could indicate a blocked crater.
“But it could also mean that the volcano might be gaining momentum, which was also observed last December 2024,” he added.
Despite the decrease in sulfur dioxide and ash emissions, Alanis warned residents not to be complacent, as the volcano remains under Alert Level 3.
"The interval between ash emissions is getting longer — from every few hours to almost once per day. Despite this, residents must remain alert."
As of 24 February, Phivolcs recorded at least 1,993 tonnes of sulfur dioxide, accompanied by three volcanic earthquakes. Ground deformation is still being observed, indicating continuous magma movement and gas pressure beneath the surface.