Campi Flegrei Spews Toxic Gas — Scientists Evacuate School & Warn Source Is Still Accelerating

Added: 2026-05-05

[00:00:00]A school in Poti was shut down this week. Not for a holiday, not for a maintenance issue. Dangerously high concentrations of carbon dioxide were measured in its basement. High enough that authorities ordered the building closed immediately and launched an investigation. At the same time, in the ground surrounding that school, elevated temperatures were detected. Not the temperatures this monitoring network has recorded before at this location.

[00:00:23]Something new, something higher. And 150 m from that school, 350 ft. The road surface had already melted, not from the sun. From volcanic heat rising through the asphalt from below, they repaved it.

[00:00:36]The volcano came through again. This is the Petronio Institute in Poti.

[00:00:41]Elementary and middle school students, children up to age 14, one of the most geologically dangerous urban environments on Earth. And this isn't the first time this school has been closed for gas. It happened last year.

[00:00:52]The school closed. Investigations were launched and then it reopened. The gas kept rising. The Petronio Institute sits on Via Sanjinaro Anano in Poti at the base of the southeastern flank of the Sulfatara crater, not on the edge of the Caldera, not in a peripheral location, directly against one of the most hazardous sections of the entire Campy Flegray volcanic system. The building itself has over a century of history.

[00:01:16][music] It has served as an orphanage, a hospital, and since the 1980s, during the last major volcanic crisis at Campy Flegre, as a school. When the 1980s crisis unfolded, the school kept operating. When this crisis began in 2005 and has been escalating [music] ever since, the school kept operating.

[00:01:34]It is an Italian state school combining elementary and middle school levels. The students inside it are children. The youngest are in primary school. What authorities measured this week in the basement was CO2 at concentrations high enough to require immediate closure and investigation. Carbon dioxide at [music] sufficient concentration displaces oxygen. It is odorless, colorless. You cannot smell it or see it before it incapacitates you. And alongside the gas, elevated ground temperatures.

[00:02:03]Scientists monitoring the site say this temperature increase is new. It hasn't been recorded at this specific location before. It suggests something is changing in the hydrothermal system directly beneath and around the building. The building itself is showing what the ground is doing. Fummeralss pushing through concrete walls, sulfur staining surfaces, steam venting through structures throughout the area. A road 150 m away melted from volcanic heat below the asphalt. They repaved it. The volcano came through again. The school sits 150 m from that road. Volcanoes don't take detours. Before we continue, have you been to Naples, Podi, or anywhere near Camp Flegre? Drop your location below. We want to know who's seen the areas we're covering. To understand why this specific school in this specific [music] location is so alarming, you need to understand exactly what surrounds it. The Petronio Institute is caught between two simultaneous hazard zones. On one side, the Sulfetara crater, the most active surface expression of the Campi Flegray system, a hydrothermal field releasing continuous volcanic gases, [music] carbon dioxide, sulfur dioxide, hydrogen sulfide through fummeralss, soil diffusion, and increasingly through the structures built on top of it. The strongest fluctuations in degassing [music] in recent years have been measured here and at Picharelli, the adjacent area. On the other side, Monteito, the epicenter zone for some of the strongest earthquakes recorded during this crisis, the area where seismic energy concentrates and releases. [music] The school sits between the primary gas hazard and the primary seismic hazard of the Campy Flegray system simultaneously. Now add the friatic risk. Friatic eruptions at Sulfetara require no magma at the surface. They need no warning swarm, no accelerating seismicity, no visible precursor that gives minutes or hours to respond. Superheated water under hydrothermal pressure encounters a cooler layer, flashes to steam, and explodes. White Island, New Zealand, 2019. A friatic eruption with no warning. 22 people dead on a remote volcanic island with a small tourist group. Sulfatara is not a remote volcanic island. It is surrounded by urban infrastructure. And in a worst case friatic event at Sulfatara, rock fragments can be thrown beyond the crater rim. The school is within that radius. Scientists monitoring the long-term gas exposure in this area say the safe limits for sulfur dioxide and carbon dioxide are likely being permanently exceeded in the Picarelli and Sulfatara [music] zone. Not occasional spikes above safe thresholds, a continuous elevated baseline that wine direction determines will reach the school on any given day. One day before the school closure, INGV, Italy's National Institute of Geoysics and Volcanology released their weekly bulletin. 95 earthquakes in the reporting period. A slight increase in carbon dioxide emissions at Picarelli.

[00:04:52]Soil CO2 flux measurements showing no significant change from previous periods. That last point sounds reassuring. It isn't. No significant change means the rising trend is continuing uninterrupted. The upward trajectory that has been building for months is not accelerating dramatically, but it is not reversing either. It is a system still moving in one direction.

[00:05:14]The broader campy flagg picture from confirmed scientific data. Magma accumulation at 6 to 8 km depth is confirmed [music] as the primary driver of the unrest. A deeper reservoir at 12 to 16 km feeding the shallower system from below. The ground has been rising continuously since 2005. 20 years of bradysism that has not resolved.

[00:05:32]Scientists were already openly discussing raising the alert level before this week's events. And then the school closed and the ground temperatures spiked. [music] The weekly bulletin and the surface events are telling the same story. Pressure in the system [music] is building. It is expressing itself at the surface in multiple ways simultaneously.

[00:05:50]Seismically through gas emissions, through ground temperature, and through structures that are visibly being compromised by the volcanic environment they sit in. The scientists monitoring the system were already at the edge of recommending a higher alert level. The school closure is the most visible public manifestation of the data they were already seeing. Here is where the story becomes something beyond volcanic science. Josephe Mastro Lorenzo has worked in a leading position at IinggV.

[00:06:15]He has been warning about what is happening at Camp Flegre since at least 2018. His professional assessment based on the actual infrastructure, the actual road network, the actual [music] building stock is this. An orderly evacuation of more than 500,000 people from the red zone around Potui is simply impossible under current conditions. Not difficult, not challenging, impossible.

[00:06:37]The main escape route from Poi runs along a highway built on bridges and elevated columns. It is structurally vulnerable to earthquake damage. During a magnitude 4.4 earthquake last year, not a major event, a moderate one. INGV personnel trying to reach their own crisis center couldn't get through for hours. Road closures on the main highway blocked access. These weren't panicking civilians. These were emergency responders going toward the crisis and they couldn't get in for hours. That is what the evacuation route looks like during a moderate earthquake on a normal day. Now add panic. Add structural damage. Add building collapses onto the roads. Add hundreds of thousands of people simultaneously deciding to leave.

[00:07:17]Poti's old buildings, many leaning on each other, poorly reinforced, constructed decades before the volcanic crisis began have already shown what a magnitude 4 earthquake does to them.

[00:07:27]Floors collapsed, roofs came down. That material lands on the streets on the evacuation routes. Maestro Lorenzo's assessment is that construction projects, heavy truck traffic, and ongoing infrastructure work are actively worsening the chaos in Boli and surrounding areas. Traffic standstills that isolate entire neighborhoods happen regularly under normal conditions. That is the realworld preview. On ordinary days without an emergency, the road network that is supposed to evacuate 500,000 people already fails under normal traffic. The plan on paper and the reality on the ground are not the same document.

[00:08:02]Infrastructure upgrades have been promised. The completion timeline late 2027. Campif Flegre does not know what year it is. The red zone population around Podoli is approximately 500,000 to 600,000 people, but a major eruption or a significant earthquake at Campi Flegre will not just move the red zone population. It will move Naples, 6 million people in the broader metropolitan area. People who watched the ground shake and the smoke rise and decided they are not waiting to find out what comes next. People who are not in the official red zone, but who are not staying. And they will all try to leave on the same roads at the same time.

[00:08:39]Roads that already fail under the traffic of a regular weekend. Roads where a magnitude 4 earthquake collapses buildings onto the pavement. Roads where construction projects and truck traffic create hours long standills on ordinary afternoons. MRO Lorenzo's warning is not a theoretical projection. He is describing what the road network already does regularly without an emergency and then asking what happens when you add panic, structural damage, debris, and millions of simultaneous decisions to leave. The evacuation routes become bottlenecks. The bottlenecks become traps. This is not an unlikely scenario.

[00:09:13]This is the scenario that the scientists monitoring Campy Flegre are specifically and repeatedly warning about since [music] 2018. with increasing urgency as the volcanic system continues to escalate. [music] Campy Flegre is not showing signs of imminent eruption. That remains the official scientific [music] position.

[00:09:30]But imminent eruption is not the only scenario that kills people at Campy Flegre. A friatic explosion at Sulfatara, no warning, no time to respond, rock fragments beyond the crater rim is a credible scenario right now. Not a theoretical future risk, a scenario that the current state of the hydrothermal system makes physically possible on any given day. A magnitude 5 earthquake collapsing unreinforced buildings onto the evacuation routes, creating bottlenecks that trap hundreds of thousands of people is a credible scenario right now. The magnitude 4 events have already demonstrated what these buildings and these roads do.

[00:10:03]Children attending school 150 m from where the road melted is not a theoretical scenario. It is happening.

[00:10:10]The pattern across all of these events is consistent. CO2 rising, ground temperatures increasing at locations where they haven't been seen before.

[00:10:19]Earthquake swarms continuing. A school closed for dangerous gas levels for the second time in 12 months. A weekly INGV bulletin confirming the upward trend continues. Each event individually has an explanation. Together, they form a picture of a volcanic system under increasing surface pressure, expressing itself in multiple ways, simultaneously in one of the most densely populated volcanic zones on Earth. The evacuation infrastructure that is supposed to protect 6 million people if this system escalates is already broken under normal conditions. The scientists who monitor this volcano have been saying so since 2018. The school kept operating. The roads kept deteriorating. The CO2 kept rising. The ground kept moving upward.

[00:11:01]Camp Flegray doesn't have to erupt to cause catastrophe. The conditions for a deadly event, friatic, seismic, or infrastructural, already exist with almost no warning time and no functioning escape. That school in Poti is the most visible symbol of exactly how seriously that warning is being taken.