In early February 2026, sulfur dioxide emissions from Mayon Volcano reached their highest level in 15 years, with a single-day measurement of 6,569 tons per day recorded on February 3. To put that in perspective, the running monthly average has more than doubled, climbing to 5,503 tons per day compared to January’s average of 2,571 tons per day. This isn’t just a number for volcanologists — it signals that something significant is happening beneath the surface, and it has direct implications for communities living near the volcano and for air quality across a much wider area.
The Philippine Institute of Volcanology and Seismology (Phivolcs) has been tracking this trend closely. The surge comes on the 29th day of Mayon’s ongoing effusive eruption, and while the volcano remains under Alert Level 3, the agency has noted that the chances of lava fountaining or a moderately explosive eruption have increased again. This is a situation that demands attention not just from those in Albay, but from anyone concerned about how volcanic activity can suddenly reshape the risks for surrounding populations. For a broader look at how environmental hazards affect communities, you might also read about urban air quality as a hidden danger in the Philippines.
What the Rising Sulfur Dioxide Levels Actually Mean
The key thing to understand here is that sulfur dioxide isn’t just a byproduct of volcanic activity — it’s one of the most reliable indicators of what’s happening deep inside a volcano. When SO₂ emissions spike without a corresponding increase in rockfalls or pyroclastic density currents (PDCs), it suggests that gas is escaping from magma that hasn’t yet reached the surface. That’s exactly the pattern Phivolcs has observed: gas output is rising, but other signs of faster lava extrusion at the summit crater have not followed suit. This dissociation between gas and lava is what makes the current situation noteworthy.
Why This Surge Demands a Closer Look at the Ground
The immediate concern for residents and local authorities is that the volcano’s behavior has become less predictable. Phivolcs has been clear that under Alert Level 3, ongoing lava effusion can continue to generate lava flows, collapse-fed rockfalls, and PDCs on the southern and eastern upper slopes. But the new element is the possibility of lava fountaining or moderate explosions that could affect all sectors of the volcano — not just the usual danger zones. This means the hazard footprint could expand quickly, and communities that have grown accustomed to Mayon’s activity may need to reassess their preparedness.
One of the more telling details from Phivolcs’ monitoring is that strong degassing from the summit was accompanied by aseismic ash emission — meaning ash was released without any detectable earthquake activity. That’s an unusual combination. Typically, ash emissions are preceded or accompanied by seismic signals, so their absence here adds another layer of complexity to the forecasting challenge. The ash plume observed on February 4 rose about 50 meters above the crater before drifting west-northwest, a reminder that even without a major explosion, the volcano can still inject material into the atmosphere that affects air quality and aviation.
Phivolcs has also flagged a secondary hazard that often gets overlooked during volcanic crises: lahars and sediment-laden streamflows. With the possibility of prolonged heavy rains over Albay due to Tropical Depression Basyang, channels draining the volcano could suddenly become pathways for destructive mudflows. This is a reminder that volcanic risk isn’t limited to the eruption itself — weather interactions can trigger cascading hazards long after the ash settles. For context on how environmental pollutants travel through ecosystems, you can read about pesticides polluting Filipino waterways.
What Often Gets Missed in the Conversation About Volcanic Gas
When people think about volcanic hazards, they usually imagine lava flows or explosive eruptions. Sulfur dioxide doesn’t get the same attention, but it should — especially when emissions reach levels like those seen at Mayon. Here’s what complicates the picture.
SO₂ Doesn’t Stay in One Place
Sulfur dioxide from a volcano can travel hundreds of kilometers downwind, affecting communities that never see ash or lava. The gas reacts with moisture in the atmosphere to form sulfate aerosols, which can cause respiratory problems, acid rain, and even temporary cooling of the local climate. The 6,569 tons per day recorded on February 3 is not just a local problem — it’s a regional air quality event. People with asthma, bronchitis, or other lung conditions should monitor air quality advisories even if they live far from the volcano’s base.
The Gas-Lava Disconnect Is a Forecasting Challenge
Normally, when a volcano is erupting effusively, you’d expect gas emissions and lava output to rise together. At Mayon, they haven’t. Gas is surging while rockfall activity and PDC generation remain relatively stable. This mismatch makes it harder for volcanologists to predict what comes next. It could mean that gas is escaping from a deeper magma source that hasn’t yet pushed to the surface — or it could mean the volcano is pressurizing in a way that might lead to a more explosive phase. Either way, the uncertainty itself is a risk factor that authorities have to plan around.
Aviation Risk Is Often Underestimated
Phivolcs specifically advised civil aviation authorities to warn pilots against flying near the summit. Ash from a sudden eruption can cause jet engines to fail, and even a small ash plume — like the 50-meter one observed — can be hazardous if an aircraft flies through it at the wrong angle. The fact that ash emissions can occur without seismic warning makes this a particularly tricky hazard to manage. Airlines operating in the Bicol region need to stay in close communication with Phivolcs, not just during major eruptions but during periods of elevated gas output like this one.
→ Scroll right to see all columns
| Hazard Type | Current Status | Primary Concern |
|---|---|---|
| SO₂ Emissions | 15-year high (6,569 t/d) | Respiratory health, acid rain, aviation |
| Lava Flows / PDCs | Ongoing on southern & eastern slopes | Direct threat to communities in danger zone |
| Ash Emissions | Aseismic, 50-m plume observed | Aviation hazard, local air quality |
| Lahars | Potential with heavy rains | Flooding and mudflows along drainage channels |
What Residents and Local Authorities Should Do Right Now
The situation at Mayon is dynamic, and the actions people take in the coming days could make a significant difference in how safely this event unfolds. Here are the concrete steps that matter most.
Stay Out of the Permanent Danger Zone
This is non-negotiable. The six-kilometer radius permanent danger zone is off-limits for a reason. Lava flows, rockfalls, and PDCs can occur with little warning, and the terrain makes escape difficult. Even if you’ve lived in the area for years and think you know the volcano’s patterns, the current gas surge changes the risk calculus. Phivolcs has been explicit: entry into this zone is prohibited. Local government units should enforce this strictly, and residents should cooperate fully.
Prepare for Possible Evacuation
If you live within the eight-kilometer radius, now is the time to review your evacuation plan — not when the alert level is raised to 4. Know your evacuation route, prepare a go-bag with essentials (medications, documents, water, food, masks), and identify where your family will stay. Phivolcs has advised residents in this zone to be ready, and readiness means having a plan you can execute within minutes, not hours. For a related perspective on how environmental hazards affect daily life, you can read about the Philippines’ trash problem and its impact on rivers.
Monitor Air Quality and Protect Your Lungs
Sulfur dioxide is a respiratory irritant. If you smell a rotten egg odor or notice a haze, limit outdoor activity, close windows, and wear an N95 mask if you need to go outside. People with asthma, children, and the elderly are most vulnerable. Local health offices should distribute masks and set up monitoring stations in communities downwind of the volcano. The ash plume drifting west-northwest on February 4 gives a clue about which areas may be most affected.
Watch for Lahars During Heavy Rain
Tropical Depression Basyang has already raised the risk of lahars along channels draining Mayon. If you live near a river or stream that originates on the volcano, be alert for sudden rises in water level, muddy flow, or a rumbling sound. These are signs that a lahar may be coming. Do not attempt to cross flowing water, and move to higher ground immediately. This is a hazard that can occur even when the volcano itself is quiet, so don’t let your guard down just because the ash stops falling.
Frequently Asked Questions About Mayon’s Sulfur Dioxide Surge
Is it safe to visit Albay right now? ▾
Can sulfur dioxide from Mayon affect Metro Manila? ▾
What’s the difference between Alert Level 3 and Alert Level 4? ▾
How is sulfur dioxide measured at a volcano? ▾
What should I do if I experience difficulty breathing? ▾
Staying Ahead of the Risk
The sulfur dioxide surge at Mayon Volcano is a reminder that volcanic hazards are not static — they evolve in ways that can catch even well-prepared communities off guard. The key takeaway here is not to panic, but to pay attention. Phivolcs has given clear guidance: stay out of the danger zone, prepare for possible evacuation, and watch for secondary hazards like lahars during heavy rain. The fact that gas emissions are rising without a corresponding increase in lava output makes this a particularly watchful moment. If this was useful, you might also want to read how the Philippines is confronting marine pollution.
Sources
Urban air quality alert: a hidden danger — A closer look at how air pollution affects health in Philippine cities, relevant for understanding the broader context of respiratory hazards.
Pesticides pollute Filipino waterways — Explores how environmental contaminants travel through ecosystems, similar to how volcanic emissions can affect air and water quality over large areas.
Mayon sulfur dioxide emissions hit 15-year high as effusive eruption continues. Manila Bulletin, 2026.
