VolcanoesVolcanoes Kill More People Long after They First Erupt – Those Deaths Are Avoidable

By Jenni Barclay and Roger Few

Published 13 September 2019

You may think of volcanic eruptions as spectacular but brief explosions. But in reality, these destructive forces wreak havoc before headlines are made and continue long after they fade. As our new research shows, it is the drawn-out nature of volcanic eruptions that can be most fatal – and understanding why is the key to saving lives.

You may think of volcanic eruptions as spectacular but brief explosions. But in reality, these destructive forces wreak havoc before headlines are made and continue long after they fade. As our new research shows, it is the drawn-out nature of volcanic eruptions that can be most fatal – and understanding why is the key to saving lives.

Most commonly, volcanoes will emit pulses of gas and solids for six to seven weeks, with quiet fizzling and rumbling punctuated by more intensive bouts of activity. Some go on for years and even decades. The recent fatal explosion in the Italian island of Stromboli is part of an eruptive sequence that officially began in 1934) but stretches back millennia – the Romans referred to the island as the “lighthouse” of the Mediterranean).

But despite this sustained risk, many who live within the reach of volatile volcanoes choose to stay in high hazard zones during an eruption, risking their lives. Studies report that between 15 and 85% of evacuated populations revisit dangerous areas while warnings are still in place.

However, research examining why so many choose to do so is limited. To better understand how to protect lives and livelihoods in the wake of eruptions, we investigated the impacts of past eruptions on the communities around volcanoes with a three-pronged approach.

Reporting on what happens to entire populations during eruptions can be a bit patchy, but what is usually well covered is when people died and where and what they were doing. We examined the circumstances of human deaths from all eruptions globally with available data over a 30-year period. We also conducted detailed interviews with people who had experienced prolonged volcanic activity in Latin America and the Caribbean. Finally, we compiled and analyzed existing case studies of communities affected by recent eruptions, to understand the relevant data they had uncovered.

Data on deaths showed that where warnings were in place, about 75 percent of the fatalities happened inside a zone where people had been asked to leave, or stay away from. More than 90 percent of these were people who were either protecting their assets or engaged in activities that contributed to their livelihoods – farming for instance. More than 70 percent of all fatalities happened a week or more after the initial eruption, despite warnings being in place.