The morning of 14 January 1993 began as field days on active volcanoes often do: with equipment, briefing, and the uneasy confidence that comes from routine. The expedition was part of the International Decade of Natural Disaster Reduction’s broader scientific attention to hazards, and Galeras had drawn a multinational team because its restless behavior made it a natural laboratory. The ascent took researchers toward the summit crater, where a small group would work in the most dangerous real estate on the mountain — the place from which any sudden blast would arrive first.
The documentary record of that day shows how ordinary the beginning could appear. There was no theatrical storm building over the crater and no dramatic announcement from the mountain that would have made a retreat obvious to everyone at once. Instead, there was the familiar logic of field volcanology: check the instruments, compare observations, weigh the latest signs of unrest, and move higher because the data demanded more direct measurement. That is what made Galeras so difficult. It was not a mountain that only revealed danger after the fact; it was a mountain that made danger legible in fragments, never in a single final sentence.
The warning signs were not absent; they were simply not decisive enough to command universal retreat. Galeras had been exhibiting unrest, and that unrest was precisely why the expedition existed. Instruments and observers indicated that the volcano was not fully settled. What was missing was the kind of unequivocal signal people wish for after the fact, a signal that says: stop now, because the next minute will kill. Volcanoes rarely provide that convenience. In a hazard as dynamic as Galeras, the evidence could support caution without collapsing into certainty.
That gap between caution and certainty is the central tension of the chapter. For some involved, the ascent was part of a legitimate scientific effort to improve understanding of an active system that threatened nearby communities. For others, the logic of the climb itself was too permissive. A summit field visit placed people in a zone where even a small explosion, rock fall, or release of high-temperature gas could be fatal. The mountain did not need a great eruption to kill; it needed only a brief one. In that sense, the summit was already a disaster scene before the eruption began.
One of the less intuitive facts about Galeras is that its danger was not proportional in any simple way to its fame. It was not a colossal stratovolcano on the scale of Krakatoa or Pinatubo. Its threat came from proximity, surprise, and the geometry of the summit. The crater rim is a trap when the vent opens sideways. Those on the top are exposed to ballistic blocks, volcanic gases, and sudden turbulence in a confined space where escape routes are limited by steep slopes and loose ash. The physical setting transformed a scientific visit into an exposure problem: how close is too close when the hazard can arrive without warning and without distance to spare the body?
The climbers on the mountain included experienced volcanologists and Colombian collaborators, people who knew how to read a fumarole and how to carry instruments across broken terrain. That competence, paradoxically, increased the risk. Experienced teams often move closer because they know what to look for, and because prior non-catastrophic visits have trained their instincts toward caution rather than retreat. The mountain becomes a workplace, and workplaces create their own normal. On a slope like Galeras, normality could be the most dangerous assumption of all, because the repeated success of previous outings teaches the body to trust conditions that remain unstable from one hour to the next.
A surprising fact, and one that matters for understanding the disaster, is how small the fatal eruption was in physical terms compared with the enormity of its effect. Later scientific accounts described it as a relatively modest explosive event, the kind that on other days might have been filed as minor unrest. But in the wrong place, at the wrong instant, a small eruption can be enough. Death on volcanoes often comes not from the largest eruptions but from the most local and immediate violence near the vent. That is what made the summit such an unforgiving setting: the difference between an instructive observation and a fatal encounter could be measured in moments, not miles.
There were also institutional warning signs. Debates over whether to proceed had already exposed a familiar problem in disaster science: when expertise is distributed across organizations and nationalities, authority becomes diffuse. One scientist may believe the risk acceptable for a short visit, another may judge it reckless, and the local observatory may have to mediate between scientific curiosity, public safety, and the pressure to continue observations. In that gap between knowledge and command, accidents are born. The problem is not always ignorance. Sometimes it is the opposite: multiple people know enough to hesitate, but no single authority is positioned to end the action decisively.
The context of the International Decade of Natural Disaster Reduction also sharpened the stakes. The era encouraged better understanding of hazards, improved monitoring, and stronger ties between science and public safety. Galeras was therefore not just a volcano under observation; it was a test of how those ideas functioned in practice when a real mountain, a real team, and a real deadline converged. The expedition embodied the promise of disaster reduction, but it also revealed its limits. Scientific presence near a hazard does not by itself reduce risk unless the chain of decision-making is clear and the threshold for withdrawal is respected.
As the team neared the summit, the environment around them would have offered the ordinary sensory cues of an active volcanic slope: cold thin air, sulfurous odors, loose rock underfoot, and the constant attention required to keep balance on a mountain where the ground itself is unstable. Those conditions are demanding even before danger becomes visible. They make people focus on footing, instruments, and companions. They narrow the world to the few meters ahead. In such terrain, even a well-trained observer can be caught in the discipline of the climb, measuring the terrain step by step while the larger threat remains just out of frame.
The forensic importance of the morning lies in that narrowing. Later inquiry into the eruption would center not only on the volcanic event itself, but on how a scientific operation could still be underway at the summit when unrest was known and the margin for error was so thin. The disaster did not hinge on a single mistake alone. It emerged from a sequence of judgments, each one plausible in isolation, that together placed people where the mountain could reach them immediately. That is what makes the chapter so severe in hindsight: the hidden danger was not hidden from everyone, but it was distributed among enough uncertain readings, enough competing duties, and enough prior success that no one moment forced a retreat.
Then the mountain changed. The onset was abrupt, with no long grace period to reconsider. The event that had been theoretical a moment before became immediate, and the climb ceased to be a field exercise. The volcano had spent itself in preparation; now it struck.