The Calbuco volcano in southern Chile erupted for the first time in more than five decades, which in the global media was covered more for its visual spectacle rather than its perception as a major catastrophe. This can be partly explained with the low threat that Calbuco poses to larger numbers of people. As reported by the BBC, “authorities have declared a red alert and evacuated more than 4,000 people within a 20km (12 mile) radius”. This is a relatively low number as the volcano is situated in a sparsely populated, mountainous area. Natural events usually turn into natural disasters when they happen in more densely populated areas. The following map shows how human settlement patterns and the global distribution of volcanoes correlate by drawing a 100km radius around each of the world’s volcanoes and then projecting this data onto a gridded population cartogram. This equal-population projection results in some of these 100km risk zones around the volcanoes to become hugely visible, because there are large populations living in this area, while other volcanoes and their risk-radius become almost invisible due to the low number of people living there. Very often, these are the decisive differences between a volcanic eruption being a natural event (or even spectacle) and a natural disaster, which these events can become in the red-shaded areas of this map:

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